Mitsubishi FX2N-4AD-TC User manual

FX2N-4AD-TC SPECIAL FUNCTION BLOCK
USER’S GUIDE
JY992D65501B
This manual contains text, diagrams and explanations which will guide the reader in the correct
installation and operation of the FX2N-4AD-TC special function block and should be read and understood
before attempting to install or use the unit.
Further information can be found in the FX PROGRAMMING MANUAL(ΙΙ) and FX0N/FX1N/FX2N/FX2NC
SERIES HARDWARE MANUAL.
Guidelines for the Safety of the User and Protection of the FX2N-4AD-TC
special function block.
This manual should be used by trained and competent personnel. The definition of such a person or
persons is as follows:
a) Any engineer using the product associated with this manual, should be of a competent nature,
trained and qualified to the local and national standards. These engineers should be fully aware of
all aspects of safety with regards to automated equipment.
b) Any commissioning or service engineer must be of a competent nature, trained and qualified to
the local and national standards.
c) All operators of the completed equipment should be trained to use this product in a safe and
coordinated manner in compliance to established safety practices.
Note: The term ‘completed equipment’ refers to a third party constructed device which contains or uses
the product associated with this manual.
Notes on the Symbols Used in this Manual
At various times throughout this manual certain symbols will be used to highlight points of information
which are intended to ensure the users personal safety and protect the integrity of equipment.
1) Indicates that the identified danger WILL cause physical and property damage.
2) Indicates that the identified danger could POSSIBLY cause physical and property
damage.
• Under no circumstances will Mitsubishi Electric be liable or responsible for any consequential damage
that may arise as a result of the installation or use of this equipment.
• All examples and diagrams shown in this manual are intended only as an aid to understanding the
text, not to guarantee operation. Mitsubishi Electric will accept no responsibility for the actual use of
the product based on these illustrative examples.
• Owing to the very great variety in possible applications for this equipment, you must satisfy yourself as
to its suitability for your own specific application.
1. INTRODUCTION
• The FX2N-4AD-TC analog block amplifies the signal from four thermocouple sensors (Type K or J) and
converts the data into 12 bit reading’s stored in the main unit. Both Centigrade (°C) and Fahrenheit
(°F) can be read.
Reading resolution is 0.4°C/0.72°F of Type K and 0.3°C/0.54°F of Type J.
• The FX2N-4AD-TC can connected to the FX0N, FX1N, FX2N and the FX2NC series Programmable
Controllers (PLC).
• All data transfers and parameter settings are adjusted via software control of the FX2N-4AD-TC; by
use of the TO/FROM applied instructions in the PLC.
• The FX2N-4AD-TC occupies 8 I/O points on the PLC expansion bus. The 8 I/O points can be allocated
from either inputs or outputs. The FX2N-4AD-TC draws 40mA from the 5V rail of the main unit or
powered extension unit.
• Thermocouples with the following specifications can be used: Type K (JIS 1602-1981)
Type J (JIS 1602-1981)
2. EXTERNAL DIMENSIONS
3. CONNECTION WITH PLC
3.1 Connection with PLC
1) Up to 4 FX2N-4AD-TC units can connect to the FX0N series PLC, up to 5 for FX1N, up to 8 for FX2N or,
up to 4 for an FX2NC series PLC, all with powered extension units.
However the following limitation exists when the undermentioned special function blocks are
connected.
FX2N: Main unit and powered extension units of 32 I/O points or less. Current consumption available
for the undermentioned special function blocks ≤190mA
FX2N: Main unit and powered extension units of 48 I/O points or more. Current consumption
available for the undermentioned special function blocks ≤300mA
FX2NC:Up to 4 undermentioned special function blocks can be connected regardless of the system I/O.
When using an FX2NC an FX2NC-CNV-IF is required.
FX0N/1N:Main unit and powered extension units. Up to 2 undermentioned special function blocks can
be connected regardless of the system I/O.
2) Each block occupies 8 I/O points (The 8 points can be allocated from either inputs or outputs).
3) FX2N-4AD-TC consumes 40mA from the 5V DC bus.
The total 5V consumption of all special function blocks connected to a main unit or extension unit
must not exceed the 5V source capacity of the system.
4) The FX2N-4AD-TC and main unit are connected by a cable on the right of the main unit.
3.2 Special function block numbers
Other special units of blocks that use FROM/TO commands, such as analog input blocks, analog output
blocks and high-speed counter blocks, can be directly connected to the main unit of the PLC or to the right
side of other extension blocks or units.
4. WIRING
4.1 Wiring
*1: The compensating cables that can be used for
connecting with the thermocouple are the following.
Type K: KX-G, KX-GS, KX-H, KX-HS,WX-G,WX-H,VX-G
Type J: JX-G, JX-H
For every 10Ωof line resistance, the compensating
cable will indicate a temperature 0.12°C higher than
actual.
Check the line resistance before using. Long
compensating cables are more prone to noise
interference, therefore a short (less than 100m)
compensating cable is recommended.
Unused channels should have a wire link connected
between the + and - terminals to prevent an errors being
detected on that channel.
*2: If there is excessive electrical noise, connect the SLD
terminal to the ground terminal on the unit.
*3: Connect the ground terminals of the FX2N-4AD-TC unit and the main unit. Use grounding on the main
unit.
*4: The 24V DC built-in supply of the PLC may be used as the power supply.
P O W E R
2 4 V
A / D
C H 4C H 3
C H 1
2 4 +
2 4 -
L +
L +
F X
2 N
- 4 A D - T C
L - L -
L +
L -
S L D
C H 1
2 4 +
2 4 - L -
C H 2
L -
L +
L +
4 ( 0 . 1 6 )
4 ( 0 . 1 6 )
5 5 ( 2 . 1 7 )
8 0 ( 3 . 1 5 )
0 ( 3 . 5 4 )
5 5 ( 2 . 1 7 )
8 7 ( 3 . 4 3 )
( 0 . 3 5 )
S L D
S L D
S L D
S L D
T e r m i n a l s c r e w s M 3 ( 0 . 1 2 )
2 4 V
L E D
A / D
L E D
D I N r a i l
m o u n t i n g s l o t
3 5 m m ( 1 . 3 8 )
M o u n t i n g h o l e s
4 . 5 m m ( 0 . 1 8 ) d i a .
E x t e n s i o n c a b l e
a n d c o n n e c t o r
Weight: Approx. 0.3 kg (0.66 lbs) Dimensions: mm (inches)
Accessories: Self adhesive labels for special function block number identification
F X - 1 6 E X
X 0 0 0 - X 0 2 7
Y 0 0 0 - Y 0 2 7
X 0 3 0
- X 0 4 7
2 N
F X - 4 8 M R - E S / U L 2 N
F X - 4 A D 2 N
N o . 2
2 N
F X - 4 A D - T C
X 0 5 0 - X 0 6 7
Y 0 3 0 - Y 0 4 7
2 N
F X - 3 2 E R
2 N
F X - 4 D A
F X - 4 8 M R - E S / U L
2 N
P O W E R
A / D
2 4 V
F X - 4 A D
2 N
P O W E R
D / A
2 4 V
F X - 4 D A
2 N
N o . 1
N o . 0
P O W E R
24V
A / D
S p e c i a l b l o c k S p e c i a l b l o c k S p e c i a l b l o c k
X 0
X 5
72 4 5 61 30
1 61 1 1 51 4 1 71 0 1 2 1 3
1 4 1 71 51 0 1 2 1 3
72 4 5 61 30
1 61 1
O U T
I N
LX 1 1 X 1 3 X 1 5 X 1 7
X 6 X 1 0 X 1 2 X 1 4 X 1 6
24+
N
C O M X 4
X 7
C O M 4
C O M 2
Y 4
Y 5
Y 6
Y 7 C O M 3
Y 1 0
Y 1 1
Y 1 2
Y 1 3
C O M 1
Y 0
Y 1
Y 2
Y 3
Y 1 4
Y 1 5
Y 1 6
Y 1 7
X 3
X 2
X 1
P O W E R
76 2 72 0 2 2 2 3 2 4 2 5 2 62 1
1 6 1 7
1 4 1 71 51 0 1 2 1 3
72 4 5 61 30 2 72 0 2 2 2 3 2 4 2 5 2 62 1
1 61 1
I N
L X 5 X 7 X 1 3 X 1 5 X 1 7 X 2 1 X 2 3 X 2 5
X 4 X 6 X 1 0 X 1 4 X 1 6 X 2 0 X 2 2 X 2 4
2 4 +N
C O M X 0
X 1
X 2
C O M 4
Y 2 4
Y 2 5
C O M 5
Y 2 7C O M 2
Y 4
Y 5
Y 6
Y 7 C O M 3
Y 1 0
Y 1 3C O M 1
Y 0 Y 2
Y 3
Y 1 4
Y 1 5
Y 2 0
Y 2 1
Y 2 2
Y 2 3
Y 2 6
P O W E R
T . V
C P U . E
P R O G . E
Connection example
Thermocouple 1
shielded CH1 3K
:
L+
24+
24-
DC/DC
converter AG
+15V
-15V
PLC
Extension cable
Grounding
(100
:
or less)
3
4
24VDC±10% 50mA 2
FX2N-4AD-TC
Analog Input Block
L-
CH1
SLD
Thermocouple 1
shielded CH4 L+
L-
SLD
3K
:
Temperature
compensation
circuit
CH4
4.2 Using crimp terminations
• Use crimp terminals as indicated on the left.
• Secure the terminal using a tightening torque of between 5 and 8
kg⋅cm.
• Wire only to the module terminals discussed in this manual. Leave all
others vacant.
5. SPECIFICATIONS
5.1 Environmental specification
5.2 Power supply specification
5.3 Performance specification
Analog Inputs
Miscellaneous
Note: Earth-tipped thermocouples are not suitable for use with this unit.
5.4 Installation location
This unit measures temperature according to the temperature difference between the temperature
measurement part (themocouple) and the terminal block. If this unit is installed at a place where the
temperature of the terminal block varies rapidly, a measuring error may occur. For this reason, the unit
should be installed at a place free from excessive temperature variation.
Item Specification
Environmental specifications Same as those for the main unit
Dielectric withstand voltage 500V AC, 1min (between all terminals and ground)
Item Specification
Analog circuits 24V DC ± 10%, 60mA
Digital circuits 5V DC, 40mA (internal power supply from the main unit)
Item Centigrade (°
°°
°C) Fahrenheit (°
°°
°F)
Both °C and °F are available by reading the appropriate buffer memory (BFM).
Input signal Thermocouple: Type K or J (either can be used for each channel), 4 channels, JIS
1602-1981
Rated temperature
range Type K -100°C to +1,200°C Type K -148°F to +2,192°F
Type J -100°C to +600°C Type J -148°F to +1,112°F
Digital output
12 bit conversion stored in 16 bit 2’s complement form
Type K -1,000 to 12,000 Type K -148°F to +2,192°F
Type J -1,000 to 6,000 Type J -148°F to +1,112°F
Resolution Type K 0.4°C Type K 0.72°F
Type J 0.3°C Type J 0.54°F
Overall accuracy
Calibration point ± (0.5% full scale +1°C) Freezing point of pure water 0°C / 32°F
Conversion speed (240ms ± 2%) ×4 channels (unused channels are not converted)
Item Centigrade (°
°°
°C) Fahrenheit (°
°°
°F)
Conversion Characteristics
Readings given at calibration
reference point 0°C/32°F (0/320)
respectively.
(subject to the overall accuracy)
Item Specification
Isolation Photo-coupler isolation between analog and digital circuits. DC/DC converter isolation of power from main unit.
No isolation between analog channels.
Number of occupied I/O points The block occupies 8 I/O points
(can be either inputs or outputs)
l e s s t h a n
6 . 2 m m ( 0 . 2 4 )
U s e M 3 ( 0 . 1 2 )
l e s s t h a n
6 . 2 m m ( 0 . 2 4 )
+6,000
-100°C
-1,000 +1,200°C
+12,000
(Type K)
(Type J)
+600°C (Type K)(Type J) -1,480 +2,192°F
+21,920
(Type K)
(Type J)
+1,112°F (Type K)(Type J)
+11,120
-148°F

FX2N-4AD-TC SPECIAL FUNCTION BLOCK
USER’S GUIDE
JY992D65501B
This manual contains text, diagrams and explanations which will guide the reader in the correct
installation and operation of the FX2N-4AD-TC special function block and should be read and understood
before attempting to install or use the unit.
Further information can be found in the FX PROGRAMMING MANUAL(ΙΙ) and FX0N/FX1N/FX2N/FX2NC
SERIES HARDWARE MANUAL.
Guidelines for the Safety of the User and Protection of the FX2N-4AD-TC
special function block.
This manual should be used by trained and competent personnel. The definition of such a person or
persons is as follows:
a) Any engineer using the product associated with this manual, should be of a competent nature,
trained and qualified to the local and national standards. These engineers should be fully aware of
all aspects of safety with regards to automated equipment.
b) Any commissioning or service engineer must be of a competent nature, trained and qualified to
the local and national standards.
c) All operators of the completed equipment should be trained to use this product in a safe and
coordinated manner in compliance to established safety practices.
Note: The term ‘completed equipment’ refers to a third party constructed device which contains or uses
the product associated with this manual.
Notes on the Symbols Used in this Manual
At various times throughout this manual certain symbols will be used to highlight points of information
which are intended to ensure the users personal safety and protect the integrity of equipment.
1) Indicates that the identified danger WILL cause physical and property damage.
2) Indicates that the identified danger could POSSIBLY cause physical and property
damage.
• Under no circumstances will Mitsubishi Electric be liable or responsible for any consequential damage
that may arise as a result of the installation or use of this equipment.
• All examples and diagrams shown in this manual are intended only as an aid to understanding the
text, not to guarantee operation. Mitsubishi Electric will accept no responsibility for the actual use of
the product based on these illustrative examples.
• Owing to the very great variety in possible applications for this equipment, you must satisfy yourself as
to its suitability for your own specific application.
1. INTRODUCTION
• The FX2N-4AD-TC analog block amplifies the signal from four thermocouple sensors (Type K or J) and
converts the data into 12 bit reading’s stored in the main unit. Both Centigrade (°C) and Fahrenheit
(°F) can be read.
Reading resolution is 0.4°C/0.72°F of Type K and 0.3°C/0.54°F of Type J.
• The FX2N-4AD-TC can connected to the FX0N, FX1N, FX2N and the FX2NC series Programmable
Controllers (PLC).
• All data transfers and parameter settings are adjusted via software control of the FX2N-4AD-TC; by
use of the TO/FROM applied instructions in the PLC.
• The FX2N-4AD-TC occupies 8 I/O points on the PLC expansion bus. The 8 I/O points can be allocated
from either inputs or outputs. The FX2N-4AD-TC draws 40mA from the 5V rail of the main unit or
powered extension unit.
• Thermocouples with the following specifications can be used: Type K (JIS 1602-1981)
Type J (JIS 1602-1981)
2. EXTERNAL DIMENSIONS
3. CONNECTION WITH PLC
3.1 Connection with PLC
1) Up to 4 FX2N-4AD-TC units can connect to the FX0N series PLC, up to 5 for FX1N, up to 8 for FX2N or,
up to 4 for an FX2NC series PLC, all with powered extension units.
However the following limitation exists when the undermentioned special function blocks are
connected.
FX2N: Main unit and powered extension units of 32 I/O points or less. Current consumption available
for the undermentioned special function blocks ≤190mA
FX2N: Main unit and powered extension units of 48 I/O points or more. Current consumption
available for the undermentioned special function blocks ≤300mA
FX2NC:Up to 4 undermentioned special function blocks can be connected regardless of the system I/O.
When using an FX2NC an FX2NC-CNV-IF is required.
FX0N/1N:Main unit and powered extension units. Up to 2 undermentioned special function blocks can
be connected regardless of the system I/O.
2) Each block occupies 8 I/O points (The 8 points can be allocated from either inputs or outputs).
3) FX2N-4AD-TC consumes 40mA from the 5V DC bus.
The total 5V consumption of all special function blocks connected to a main unit or extension unit
must not exceed the 5V source capacity of the system.
4) The FX2N-4AD-TC and main unit are connected by a cable on the right of the main unit.
3.2 Special function block numbers
Other special units of blocks that use FROM/TO commands, such as analog input blocks, analog output
blocks and high-speed counter blocks, can be directly connected to the main unit of the PLC or to the right
side of other extension blocks or units.
4. WIRING
4.1 Wiring
*1: The compensating cables that can be used for
connecting with the thermocouple are the following.
Type K: KX-G, KX-GS, KX-H, KX-HS,WX-G,WX-H,VX-G
Type J: JX-G, JX-H
For every 10Ωof line resistance, the compensating
cable will indicate a temperature 0.12°C higher than
actual.
Check the line resistance before using. Long
compensating cables are more prone to noise
interference, therefore a short (less than 100m)
compensating cable is recommended.
Unused channels should have a wire link connected
between the + and - terminals to prevent an errors being
detected on that channel.
*2: If there is excessive electrical noise, connect the SLD
terminal to the ground terminal on the unit.
*3: Connect the ground terminals of the FX2N-4AD-TC unit and the main unit. Use grounding on the main
unit.
*4: The 24V DC built-in supply of the PLC may be used as the power supply.
P O W E R
2 4 V
A / D
C H 4C H 3
C H 1
2 4 +
2 4 -
L +
L +
F X
2 N
- 4 A D - T C
L - L -
L +
L -
S L D
C H 1
2 4 +
2 4 - L -
C H 2
L -
L +
L +
4 ( 0 . 1 6 )
4 ( 0 . 1 6 )
5 5 ( 2 . 1 7 )
8 0 ( 3 . 1 5 )
0 ( 3 . 5 4 )
5 5 ( 2 . 1 7 )
8 7 ( 3 . 4 3 )
( 0 . 3 5 )
S L D
S L D
S L D
S L D
T e r m i n a l s c r e w s M 3 ( 0 . 1 2 )
2 4 V
L E D
A / D
L E D
D I N r a i l
m o u n t i n g s l o t
3 5 m m ( 1 . 3 8 )
M o u n t i n g h o l e s
4 . 5 m m ( 0 . 1 8 ) d i a .
E x t e n s i o n c a b l e
a n d c o n n e c t o r
Weight: Approx. 0.3 kg (0.66 lbs) Dimensions: mm (inches)
Accessories: Self adhesive labels for special function block number identification
F X - 1 6 E X
X 0 0 0 - X 0 2 7
Y 0 0 0 - Y 0 2 7
X 0 3 0
- X 0 4 7
2 N
F X - 4 8 M R - E S / U L 2 N
F X - 4 A D 2 N
N o . 2
2 N
F X - 4 A D - T C
X 0 5 0 - X 0 6 7
Y 0 3 0 - Y 0 4 7
2 N
F X - 3 2 E R
2 N
F X - 4 D A
F X - 4 8 M R - E S / U L
2 N
P O W E R
A / D
2 4 V
F X - 4 A D
2 N
P O W E R
D / A
2 4 V
F X - 4 D A
2 N
N o . 1
N o . 0
P O W E R
24V
A / D
S p e c i a l b l o c k S p e c i a l b l o c k S p e c i a l b l o c k
X 0
X 5
72 4 5 61 30
1 61 1 1 51 4 1 71 0 1 2 1 3
1 4 1 71 51 0 1 2 1 3
72 4 5 61 30
1 61 1
O U T
I N
LX 1 1 X 1 3 X 1 5 X 1 7
X 6 X 1 0 X 1 2 X 1 4 X 1 6
24+
N
C O M X 4
X 7
C O M 4
C O M 2
Y 4
Y 5
Y 6
Y 7 C O M 3
Y 1 0
Y 1 1
Y 1 2
Y 1 3
C O M 1
Y 0
Y 1
Y 2
Y 3
Y 1 4
Y 1 5
Y 1 6
Y 1 7
X 3
X 2
X 1
P O W E R
76 2 72 0 2 2 2 3 2 4 2 5 2 62 1
1 6 1 7
1 4 1 71 51 0 1 2 1 3
72 4 5 61 30 2 72 0 2 2 2 3 2 4 2 5 2 62 1
1 61 1
I N
L X 5 X 7 X 1 3 X 1 5 X 1 7 X 2 1 X 2 3 X 2 5
X 4 X 6 X 1 0 X 1 4 X 1 6 X 2 0 X 2 2 X 2 4
2 4 +N
C O M X 0
X 1
X 2
C O M 4
Y 2 4
Y 2 5
C O M 5
Y 2 7C O M 2
Y 4
Y 5
Y 6
Y 7 C O M 3
Y 1 0
Y 1 3C O M 1
Y 0 Y 2
Y 3
Y 1 4
Y 1 5
Y 2 0
Y 2 1
Y 2 2
Y 2 3
Y 2 6
P O W E R
T . V
C P U . E
P R O G . E
Connection example
Thermocouple 1
shielded CH1 3K
:
L+
24+
24-
DC/DC
converter AG
+15V
-15V
PLC
Extension cable
Grounding
(100
:
or less)
3
4
24VDC±10% 50mA 2
FX2N-4AD-TC
Analog Input Block
L-
CH1
SLD
Thermocouple 1
shielded CH4 L+
L-
SLD
3K
:
Temperature
compensation
circuit
CH4
4.2 Using crimp terminations
• Use crimp terminals as indicated on the left.
• Secure the terminal using a tightening torque of between 5 and 8
kg⋅cm.
• Wire only to the module terminals discussed in this manual. Leave all
others vacant.
5. SPECIFICATIONS
5.1 Environmental specification
5.2 Power supply specification
5.3 Performance specification
Analog Inputs
Miscellaneous
Note: Earth-tipped thermocouples are not suitable for use with this unit.
5.4 Installation location
This unit measures temperature according to the temperature difference between the temperature
measurement part (themocouple) and the terminal block. If this unit is installed at a place where the
temperature of the terminal block varies rapidly, a measuring error may occur. For this reason, the unit
should be installed at a place free from excessive temperature variation.
Item Specification
Environmental specifications Same as those for the main unit
Dielectric withstand voltage 500V AC, 1min (between all terminals and ground)
Item Specification
Analog circuits 24V DC ± 10%, 60mA
Digital circuits 5V DC, 40mA (internal power supply from the main unit)
Item Centigrade (°
°°
°C) Fahrenheit (°
°°
°F)
Both °C and °F are available by reading the appropriate buffer memory (BFM).
Input signal Thermocouple: Type K or J (either can be used for each channel), 4 channels, JIS
1602-1981
Rated temperature
range Type K -100°C to +1,200°C Type K -148°F to +2,192°F
Type J -100°C to +600°C Type J -148°F to +1,112°F
Digital output
12 bit conversion stored in 16 bit 2’s complement form
Type K -1,000 to 12,000 Type K -148°F to +2,192°F
Type J -1,000 to 6,000 Type J -148°F to +1,112°F
Resolution Type K 0.4°C Type K 0.72°F
Type J 0.3°C Type J 0.54°F
Overall accuracy
Calibration point ± (0.5% full scale +1°C) Freezing point of pure water 0°C / 32°F
Conversion speed (240ms ± 2%) ×4 channels (unused channels are not converted)
Item Centigrade (°
°°
°C) Fahrenheit (°
°°
°F)
Conversion Characteristics
Readings given at calibration
reference point 0°C/32°F (0/320)
respectively.
(subject to the overall accuracy)
Item Specification
Isolation Photo-coupler isolation between analog and digital circuits. DC/DC converter isolation of power from main unit.
No isolation between analog channels.
Number of occupied I/O points The block occupies 8 I/O points
(can be either inputs or outputs)
l e s s t h a n
6 . 2 m m ( 0 . 2 4 )
U s e M 3 ( 0 . 1 2 )
l e s s t h a n
6 . 2 m m ( 0 . 2 4 )
+6,000
-100°C
-1,000 +1,200°C
+12,000
(Type K)
(Type J)
+600°C (Type K)(Type J) -1,480 +2,192°F
+21,920
(Type K)
(Type J)
+1,112°F (Type K)(Type J)
+11,120
-148°F

FX2N-4AD-TC SPECIAL FUNCTION BLOCK
USER’S GUIDE
JY992D65501B
This manual contains text, diagrams and explanations which will guide the reader in the correct
installation and operation of the FX2N-4AD-TC special function block and should be read and understood
before attempting to install or use the unit.
Further information can be found in the FX PROGRAMMING MANUAL(ΙΙ) and FX0N/FX1N/FX2N/FX2NC
SERIES HARDWARE MANUAL.
Guidelines for the Safety of the User and Protection of the FX2N-4AD-TC
special function block.
This manual should be used by trained and competent personnel. The definition of such a person or
persons is as follows:
a) Any engineer using the product associated with this manual, should be of a competent nature,
trained and qualified to the local and national standards. These engineers should be fully aware of
all aspects of safety with regards to automated equipment.
b) Any commissioning or service engineer must be of a competent nature, trained and qualified to
the local and national standards.
c) All operators of the completed equipment should be trained to use this product in a safe and
coordinated manner in compliance to established safety practices.
Note: The term ‘completed equipment’ refers to a third party constructed device which contains or uses
the product associated with this manual.
Notes on the Symbols Used in this Manual
At various times throughout this manual certain symbols will be used to highlight points of information
which are intended to ensure the users personal safety and protect the integrity of equipment.
1) Indicates that the identified danger WILL cause physical and property damage.
2) Indicates that the identified danger could POSSIBLY cause physical and property
damage.
• Under no circumstances will Mitsubishi Electric be liable or responsible for any consequential damage
that may arise as a result of the installation or use of this equipment.
• All examples and diagrams shown in this manual are intended only as an aid to understanding the
text, not to guarantee operation. Mitsubishi Electric will accept no responsibility for the actual use of
the product based on these illustrative examples.
• Owing to the very great variety in possible applications for this equipment, you must satisfy yourself as
to its suitability for your own specific application.
1. INTRODUCTION
• The FX2N-4AD-TC analog block amplifies the signal from four thermocouple sensors (Type K or J) and
converts the data into 12 bit reading’s stored in the main unit. Both Centigrade (°C) and Fahrenheit
(°F) can be read.
Reading resolution is 0.4°C/0.72°F of Type K and 0.3°C/0.54°F of Type J.
• The FX2N-4AD-TC can connected to the FX0N, FX1N, FX2N and the FX2NC series Programmable
Controllers (PLC).
• All data transfers and parameter settings are adjusted via software control of the FX2N-4AD-TC; by
use of the TO/FROM applied instructions in the PLC.
• The FX2N-4AD-TC occupies 8 I/O points on the PLC expansion bus. The 8 I/O points can be allocated
from either inputs or outputs. The FX2N-4AD-TC draws 40mA from the 5V rail of the main unit or
powered extension unit.
• Thermocouples with the following specifications can be used: Type K (JIS 1602-1981)
Type J (JIS 1602-1981)
2. EXTERNAL DIMENSIONS
3. CONNECTION WITH PLC
3.1 Connection with PLC
1) Up to 4 FX2N-4AD-TC units can connect to the FX0N series PLC, up to 5 for FX1N, up to 8 for FX2N or,
up to 4 for an FX2NC series PLC, all with powered extension units.
However the following limitation exists when the undermentioned special function blocks are
connected.
FX2N: Main unit and powered extension units of 32 I/O points or less. Current consumption available
for the undermentioned special function blocks ≤190mA
FX2N: Main unit and powered extension units of 48 I/O points or more. Current consumption
available for the undermentioned special function blocks ≤300mA
FX2NC:Up to 4 undermentioned special function blocks can be connected regardless of the system I/O.
When using an FX2NC an FX2NC-CNV-IF is required.
FX0N/1N:Main unit and powered extension units. Up to 2 undermentioned special function blocks can
be connected regardless of the system I/O.
2) Each block occupies 8 I/O points (The 8 points can be allocated from either inputs or outputs).
3) FX2N-4AD-TC consumes 40mA from the 5V DC bus.
The total 5V consumption of all special function blocks connected to a main unit or extension unit
must not exceed the 5V source capacity of the system.
4) The FX2N-4AD-TC and main unit are connected by a cable on the right of the main unit.
3.2 Special function block numbers
Other special units of blocks that use FROM/TO commands, such as analog input blocks, analog output
blocks and high-speed counter blocks, can be directly connected to the main unit of the PLC or to the right
side of other extension blocks or units.
4. WIRING
4.1 Wiring
*1: The compensating cables that can be used for
connecting with the thermocouple are the following.
Type K: KX-G, KX-GS, KX-H, KX-HS,WX-G,WX-H,VX-G
Type J: JX-G, JX-H
For every 10Ωof line resistance, the compensating
cable will indicate a temperature 0.12°C higher than
actual.
Check the line resistance before using. Long
compensating cables are more prone to noise
interference, therefore a short (less than 100m)
compensating cable is recommended.
Unused channels should have a wire link connected
between the + and - terminals to prevent an errors being
detected on that channel.
*2: If there is excessive electrical noise, connect the SLD
terminal to the ground terminal on the unit.
*3: Connect the ground terminals of the FX2N-4AD-TC unit and the main unit. Use grounding on the main
unit.
*4: The 24V DC built-in supply of the PLC may be used as the power supply.
P O W E R
2 4 V
A / D
C H 4C H 3
C H 1
2 4 +
2 4 -
L +
L +
F X
2 N
- 4 A D - T C
L - L -
L +
L -
S L D
C H 1
2 4 +
2 4 - L -
C H 2
L -
L +
L +
4 ( 0 . 1 6 )
4 ( 0 . 1 6 )
5 5 ( 2 . 1 7 )
8 0 ( 3 . 1 5 )
0 ( 3 . 5 4 )
5 5 ( 2 . 1 7 )
8 7 ( 3 . 4 3 )
( 0 . 3 5 )
S L D
S L D
S L D
S L D
T e r m i n a l s c r e w s M 3 ( 0 . 1 2 )
2 4 V
L E D
A / D
L E D
D I N r a i l
m o u n t i n g s l o t
3 5 m m ( 1 . 3 8 )
M o u n t i n g h o l e s
4 . 5 m m ( 0 . 1 8 ) d i a .
E x t e n s i o n c a b l e
a n d c o n n e c t o r
Weight: Approx. 0.3 kg (0.66 lbs) Dimensions: mm (inches)
Accessories: Self adhesive labels for special function block number identification
F X - 1 6 E X
X 0 0 0 - X 0 2 7
Y 0 0 0 - Y 0 2 7
X 0 3 0
- X 0 4 7
2 N
F X - 4 8 M R - E S / U L 2 N
F X - 4 A D 2 N
N o . 2
2 N
F X - 4 A D - T C
X 0 5 0 - X 0 6 7
Y 0 3 0 - Y 0 4 7
2 N
F X - 3 2 E R
2 N
F X - 4 D A
F X - 4 8 M R - E S / U L
2 N
P O W E R
A / D
2 4 V
F X - 4 A D
2 N
P O W E R
D / A
2 4 V
F X - 4 D A
2 N
N o . 1
N o . 0
P O W E R
24V
A / D
S p e c i a l b l o c k S p e c i a l b l o c k S p e c i a l b l o c k
X 0
X 5
72 4 5 61 30
1 61 1 1 51 4 1 71 0 1 2 1 3
1 4 1 71 51 0 1 2 1 3
72 4 5 61 30
1 61 1
O U T
I N
LX 1 1 X 1 3 X 1 5 X 1 7
X 6 X 1 0 X 1 2 X 1 4 X 1 6
24+
N
C O M X 4
X 7
C O M 4
C O M 2
Y 4
Y 5
Y 6
Y 7 C O M 3
Y 1 0
Y 1 1
Y 1 2
Y 1 3
C O M 1
Y 0
Y 1
Y 2
Y 3
Y 1 4
Y 1 5
Y 1 6
Y 1 7
X 3
X 2
X 1
P O W E R
76 2 72 0 2 2 2 3 2 4 2 5 2 62 1
1 6 1 7
1 4 1 71 51 0 1 2 1 3
72 4 5 61 30 2 72 0 2 2 2 3 2 4 2 5 2 62 1
1 61 1
I N
L X 5 X 7 X 1 3 X 1 5 X 1 7 X 2 1 X 2 3 X 2 5
X 4 X 6 X 1 0 X 1 4 X 1 6 X 2 0 X 2 2 X 2 4
2 4 +N
C O M X 0
X 1
X 2
C O M 4
Y 2 4
Y 2 5
C O M 5
Y 2 7C O M 2
Y 4
Y 5
Y 6
Y 7 C O M 3
Y 1 0
Y 1 3C O M 1
Y 0 Y 2
Y 3
Y 1 4
Y 1 5
Y 2 0
Y 2 1
Y 2 2
Y 2 3
Y 2 6
P O W E R
T . V
C P U . E
P R O G . E
Connection example
Thermocouple 1
shielded CH1 3K
:
L+
24+
24-
DC/DC
converter AG
+15V
-15V
PLC
Extension cable
Grounding
(100
:
or less)
3
4
24VDC±10% 50mA 2
FX2N-4AD-TC
Analog Input Block
L-
CH1
SLD
Thermocouple 1
shielded CH4 L+
L-
SLD
3K
:
Temperature
compensation
circuit
CH4
4.2 Using crimp terminations
• Use crimp terminals as indicated on the left.
• Secure the terminal using a tightening torque of between 5 and 8
kg⋅cm.
• Wire only to the module terminals discussed in this manual. Leave all
others vacant.
5. SPECIFICATIONS
5.1 Environmental specification
5.2 Power supply specification
5.3 Performance specification
Analog Inputs
Miscellaneous
Note: Earth-tipped thermocouples are not suitable for use with this unit.
5.4 Installation location
This unit measures temperature according to the temperature difference between the temperature
measurement part (themocouple) and the terminal block. If this unit is installed at a place where the
temperature of the terminal block varies rapidly, a measuring error may occur. For this reason, the unit
should be installed at a place free from excessive temperature variation.
Item Specification
Environmental specifications Same as those for the main unit
Dielectric withstand voltage 500V AC, 1min (between all terminals and ground)
Item Specification
Analog circuits 24V DC ± 10%, 60mA
Digital circuits 5V DC, 40mA (internal power supply from the main unit)
Item Centigrade (°
°°
°C) Fahrenheit (°
°°
°F)
Both °C and °F are available by reading the appropriate buffer memory (BFM).
Input signal Thermocouple: Type K or J (either can be used for each channel), 4 channels, JIS
1602-1981
Rated temperature
range Type K -100°C to +1,200°C Type K -148°F to +2,192°F
Type J -100°C to +600°C Type J -148°F to +1,112°F
Digital output
12 bit conversion stored in 16 bit 2’s complement form
Type K -1,000 to 12,000 Type K -148°F to +2,192°F
Type J -1,000 to 6,000 Type J -148°F to +1,112°F
Resolution Type K 0.4°C Type K 0.72°F
Type J 0.3°C Type J 0.54°F
Overall accuracy
Calibration point ± (0.5% full scale +1°C) Freezing point of pure water 0°C / 32°F
Conversion speed (240ms ± 2%) ×4 channels (unused channels are not converted)
Item Centigrade (°
°°
°C) Fahrenheit (°
°°
°F)
Conversion Characteristics
Readings given at calibration
reference point 0°C/32°F (0/320)
respectively.
(subject to the overall accuracy)
Item Specification
Isolation Photo-coupler isolation between analog and digital circuits. DC/DC converter isolation of power from main unit.
No isolation between analog channels.
Number of occupied I/O points The block occupies 8 I/O points
(can be either inputs or outputs)
l e s s t h a n
6 . 2 m m ( 0 . 2 4 )
U s e M 3 ( 0 . 1 2 )
l e s s t h a n
6 . 2 m m ( 0 . 2 4 )
+6,000
-100°C
-1,000 +1,200°C
+12,000
(Type K)
(Type J)
+600°C (Type K)(Type J) -1,480 +2,192°F
+21,920
(Type K)
(Type J)
+1,112°F (Type K)(Type J)
+11,120
-148°F

HEAD OFFICE : MITSUBISHI DENKI BLDG MARUNOUTI TOKYO 100-8310 TELEX : J24532 CABLE MELCO TOKYO
HIMEJI WORKS : 840, CHIYODA CHO, HIMEJI, JAPAN
6. ALLOCATION OF BUFFER MEMORIES (BFM)
6.1 Buffer memories
The FX2N-4AD-TC communicates
with the PLC via buffer memories.
BFMs #21 to #27 and #31 are
reserved.
All non reserved BFMs can be read
by the PLC using the FROM
instruction.
BFMs (buffer memories) marked
with an “*” can be written to, the
special function block using the TO
instruction.
1) Buffer Memory BFM #0: Thermocouple Type K or J selection mode
BFM #0 is used to select Type K or J thermocouples for each channel. Each digit of a 4 digit
hexadecimal number corresponds to one channel, the least significant digit being channel 1.
• A/D conversion time is 240ms per channel. When “3" (unused) is set for a channel, A/D conversion is
not executed for that channel, therefore, the total conversion time is decreased. In the above example,
the conversion time is as follows:
240ms (conversion time per channel) ×2channels (number of channels used) = 480ms (total
conversion time)
2) Buffer Memory BFMs #1 to #4: Number of temperature readings to be averaged
When the number of temperature readings to be averaged is specified for BFMs #1 to #4, the
averaged data is stored in BFMs #5 to #8 (°C) and #13 to #16 (°F). Only the range 1 to 256 is valid for
the number of temperature readings to be averaged. If a value outside of this range is entered, a
default value of 8 is used.
3) Buffer Memory BFMs #9 to #12 and #17 to #20: Present temperature
These BFMs store the present value of the input data. This value is stored in units of 0.1°C or 0.1°F,
but the resolution is only 0.4°C or 0.72°F for Type K and 0.3°C or 0.54°F for Type J.
6.2 Status Information
1) Buffer Memory BFM #28: Digital range error latch
BFM #29 b10(digital range error) is used to judge whether the measured temperature is within the
unit’s range.
BFM #28 latches the error status of each channel and can be used to check for thermocouple
disconnection.
Low : Latches ON when the temperature measurement data drops below the lowest
temperature limit.
High : Turns ON when the temperature measurement data rises above the highest
temperature limit, or when a thermocouple is disconnected.
When an error occurs the temperature data before the error is latched. If the measured value returns
to within valid limits the temperature data returns to normal operation. (Note: The error remains
latched in (BFM #28))
An error can be cleared by writing K0 to BFM #28 using the TO instruction or turning off the power.
b15 or b8 b7 b6 b5 b4 b3 b2 b1 b0
Not used High Low High Low High Low High Low
CH4 CH3 CH2 CH1
BFM CONTENTS
*#0 Thermocouple Type K or J selection mode.
At shipment: H0000
*# 1 - #4 CH1 to CH4 Averaged temperature reading to be
averaged (1 to 256) Default = 8
#5 - #8 CH1 to CH4 Averaged temperature in 0.1°C units
#9 - #12 CH1 to CH4 Present temperature in 0.1°C units
#13 - #16 CH1 to CH4 Averaged temperature in 0.1°F units
#17 - #20 CH1 to CH4 Present temperature in 0.1°F units
#21 - #27 Reserved
*#28 Digital range error latch
#29 Error status
#30 Identification code K2030
#31 Reserved
H 3 3 1 0CH1
CH2
CH3
CH4
0 = K type
1 = J type
3 = Not used
[ Example ]
2) Buffer Memory BFM #29: Error status
3) Identification Code Buffer Memory BFM #30
The identification code or ID number for this Special Block is read from buffer memory BFM #30 using
the FROM instruction. This number for the FX2N-4AD-TC unit is K2030. The PLC can use this facility in
its program to identify the special block before commencing data transfer to and from the special block.
7. SYSTEM BLOCK DIAGRAM
8. EXAMPLE PROGRAM
In the program shown below, the FX2N-4AD-TC occupies the position of special block number 2 (that is
the third closest block to the PLC). A Type K thermocouple is used on CH1 and a Type J on CH2. CH3 and
CH4 are not used. The averaging count is four. The averaged values in degrees C of input channels CH1
and CH2 are stored respectively in data registers D0 and D1.
Bit devices of BFM #29 ON OFF
b0 : Error When either b2 or b3 is ON A/D conversion is stopped for
the error channel No error
b1 : Not used 
b2 : Power source 24V DC power supply failure power supply normal
b3 : Hardware error A/D converter or other
hardware failure Hardware Normal
b4 to b9 : Not used 
b10 : Digital range error Digital output/analog input value is outside the specified
range. Digital output value is normal.
b11 : Averaging number error Selected number of averaged results is outside the available
range -see BFM #1 to #4
Averaging is normal.
(between 1 to 256)
b12 to b15 : Not used 
Non-
contact
analog
switch
CPU
System
ROM
Buffer
Memory
RAM
A/D
converter
PLC
Command
information
write and
data status
read
24V DC
Power Source
5V Power
Supply
POWER
LED
Photocoupler
±15V
CH1
CH2
CH3
CH4
A/D
LED
Cyclic switching
FX
2N
-4AD-TC Analog Block
DC/DC
converter
Gain and offset
values are
stored in the
EEPROM
Control
signals
Converted
data
24V
LED
FROM
TO
5V
Analog Input
M8002
Initial
Pulse
K2 K30 D2 K1
Y010
FNC78
FROM
K2030 D2 M0
FNC10
CMP
M8000
RUN
monitor
K2 K29 K4M10 K1
FNC78
FROM
M10
M8002 K2 K0 H3310 K1
FNC79
TO
Initial
Pulse
Error found
Specify the type of thermocouples.
H3310 R Block No.2 BFM#0
CH4 and CH3: not used
CH2: Type J(1)
CH1: Type K(0)
Block No.2 BFM #30 R (D2)
Identification code
When (K2030) = (D2), M1 = ON.
i.e. When identification code is K2030, M1 = ON.
This initial step checks that the special function block placed at position 2 is actually
an FX
2N
-4AD-TC, i.e. its unit identification number is 2030 (BFM #30). This step is
optional, but it provides a software check that the system has been configured
correctly.
Block No.2 BFM #29 R (K4M10)
Transfer the error status to (M25 to M10).
When error is found, M10 = ON
Represents b0 BFM #29
This step provides optional monitoring of the FX
2N
-4AD-TC Error Buffer Memory (#29).
If there is an Error on the FX
2N
-4AD-TC, bit b0 of BFM #29 will be set on. This can be
read by this program step, and output as a bit device in the PLC (Y010 in this example).
Additional Error devices can be output in a similar manner, e.g. b10 BFM #29 Digital
range error. (see below)
Y010
M8000 K2 K29 K4M10 K1
FNC78
FROM
M10
Y011
M20
Represents b0 BFM #29
Represents b10 BFM #29
9. DIAGNOSTICS
9.1 Preliminary checks
I. Check whether the input/output wiring and/or extension cables are properly connected on the FX2N-
4AD-TC analog special function block.
II. Check that the PLC system configuration limits have not been exceeded, i.e. the number of special
function blocks and the total system I/O are within the specified range.
III. Ensure that the correct operating range has been selected for the application.
IV. Check that there is no power overload on either the 5V or 24V power sources, remember the loading
on the main unit or a powered extension unit varies according to the number of extension blocks or
special function blocks connected.
V. Make sure that the main unit has been switched to RUN.
9.2 Error checking
If the FX2N-4AD-TC special function block does not seem to operate normally, check the following items.
• Check the status of the POWER LED.
Lit :The extension cable is properly connected.
Otherwise :Check the connection of the extension cable.
• Check the external wiring.
• Check the status of the “24V” LED (top right corner of the FX2N-4AD-TC).
Lit :FX2N-4AD-TC is ON, 24V DC power source is ON.
Otherwise :Possible 24V DC power failure, if ON possible FX2N-4AD-TC failure.
• Check the status of the “A/D” LED (top right corner of the FX2N-4AD-TC).
Lit :A/D conversion is proceeding normally.
Otherwise :Check buffer memory #29 (error status). If any bits (b0, b2, b3) are ON, then this is why
the A/D LED is OFF.
10.EMC CONSIDERATIONS
Electromagnetic compatibility or EMC must be considered before using the FX2N-4AD-TC.
Mitsubishi recommend that the thermocouple sensors used, should be fitted with a form of seild or
screening as protection against EMC noise.
If some form of cable protection is used, the “Shield” must be terminated at the terminals
as shown in chapter 2.
Because of the delicate nature of all analog signals, failure to take good EMC precautions could lead to
EMC noise induced errors; up to ±10% of actual values. This is an absolute worst case figure, users who
do take good precautions can expect operation within normal tolerances.
EMC considerations should include selection of good quality cables, good routing of those cables away
from potential noise sources.
Additionally it is recommended that signal averaging is used as this will reduce the effects of random
noise “spikes”.
M1 K2 K1 K4 K2
FNC79
TO
K2 K5 D0 K2
FNC78
FROM
P
K2 K29 K4M10 K1
FNC78
FROM
special
block No.2 FX
2N
-4AD-TC
BFM number result
destination No. of
words read
(K4) →(BFM #1), (K4) →(BFM #2)
Number of samples is changed to four on both CH1 and
CH2.
(BFM #5) →(D0), (BFM #6) →(D1)
Transfer the averaged temperature value in °C to the
data registers.
This step is the actual reading of the FX
2N
-4AD-TC input channels. It is essentially the
only program step which is needed. The "TO" instruction in this example, sets the input
channels, CH1 and CH2, to take the average reading of four samples.
The "FROM" instruction reads the average temperatures (BFM #5 and #6) for input
channels CH1 and CH2 of the FX
2N
-4AD-TC. If direct temperature readings are
required BFM #9 and #10 should be read instead, e.g.
SLD
Manual number: JY992D65501
Manual revision: B
Date : SEPTEMBER 2002

HEAD OFFICE : MITSUBISHI DENKI BLDG MARUNOUTI TOKYO 100-8310 TELEX : J24532 CABLE MELCO TOKYO
HIMEJI WORKS : 840, CHIYODA CHO, HIMEJI, JAPAN
6. ALLOCATION OF BUFFER MEMORIES (BFM)
6.1 Buffer memories
The FX2N-4AD-TC communicates
with the PLC via buffer memories.
BFMs #21 to #27 and #31 are
reserved.
All non reserved BFMs can be read
by the PLC using the FROM
instruction.
BFMs (buffer memories) marked
with an “*” can be written to, the
special function block using the TO
instruction.
1) Buffer Memory BFM #0: Thermocouple Type K or J selection mode
BFM #0 is used to select Type K or J thermocouples for each channel. Each digit of a 4 digit
hexadecimal number corresponds to one channel, the least significant digit being channel 1.
• A/D conversion time is 240ms per channel. When “3" (unused) is set for a channel, A/D conversion is
not executed for that channel, therefore, the total conversion time is decreased. In the above example,
the conversion time is as follows:
240ms (conversion time per channel) ×2channels (number of channels used) = 480ms (total
conversion time)
2) Buffer Memory BFMs #1 to #4: Number of temperature readings to be averaged
When the number of temperature readings to be averaged is specified for BFMs #1 to #4, the
averaged data is stored in BFMs #5 to #8 (°C) and #13 to #16 (°F). Only the range 1 to 256 is valid for
the number of temperature readings to be averaged. If a value outside of this range is entered, a
default value of 8 is used.
3) Buffer Memory BFMs #9 to #12 and #17 to #20: Present temperature
These BFMs store the present value of the input data. This value is stored in units of 0.1°C or 0.1°F,
but the resolution is only 0.4°C or 0.72°F for Type K and 0.3°C or 0.54°F for Type J.
6.2 Status Information
1) Buffer Memory BFM #28: Digital range error latch
BFM #29 b10(digital range error) is used to judge whether the measured temperature is within the
unit’s range.
BFM #28 latches the error status of each channel and can be used to check for thermocouple
disconnection.
Low : Latches ON when the temperature measurement data drops below the lowest
temperature limit.
High : Turns ON when the temperature measurement data rises above the highest
temperature limit, or when a thermocouple is disconnected.
When an error occurs the temperature data before the error is latched. If the measured value returns
to within valid limits the temperature data returns to normal operation. (Note: The error remains
latched in (BFM #28))
An error can be cleared by writing K0 to BFM #28 using the TO instruction or turning off the power.
b15 or b8 b7 b6 b5 b4 b3 b2 b1 b0
Not used High Low High Low High Low High Low
CH4 CH3 CH2 CH1
BFM CONTENTS
*#0 Thermocouple Type K or J selection mode.
At shipment: H0000
*# 1 - #4 CH1 to CH4 Averaged temperature reading to be
averaged (1 to 256) Default = 8
#5 - #8 CH1 to CH4 Averaged temperature in 0.1°C units
#9 - #12 CH1 to CH4 Present temperature in 0.1°C units
#13 - #16 CH1 to CH4 Averaged temperature in 0.1°F units
#17 - #20 CH1 to CH4 Present temperature in 0.1°F units
#21 - #27 Reserved
*#28 Digital range error latch
#29 Error status
#30 Identification code K2030
#31 Reserved
H 3 3 1 0CH1
CH2
CH3
CH4
0 = K type
1 = J type
3 = Not used
[ Example ]
2) Buffer Memory BFM #29: Error status
3) Identification Code Buffer Memory BFM #30
The identification code or ID number for this Special Block is read from buffer memory BFM #30 using
the FROM instruction. This number for the FX2N-4AD-TC unit is K2030. The PLC can use this facility in
its program to identify the special block before commencing data transfer to and from the special block.
7. SYSTEM BLOCK DIAGRAM
8. EXAMPLE PROGRAM
In the program shown below, the FX2N-4AD-TC occupies the position of special block number 2 (that is
the third closest block to the PLC). A Type K thermocouple is used on CH1 and a Type J on CH2. CH3 and
CH4 are not used. The averaging count is four. The averaged values in degrees C of input channels CH1
and CH2 are stored respectively in data registers D0 and D1.
Bit devices of BFM #29 ON OFF
b0 : Error When either b2 or b3 is ON A/D conversion is stopped for
the error channel No error
b1 : Not used 
b2 : Power source 24V DC power supply failure power supply normal
b3 : Hardware error A/D converter or other
hardware failure Hardware Normal
b4 to b9 : Not used 
b10 : Digital range error Digital output/analog input value is outside the specified
range. Digital output value is normal.
b11 : Averaging number error Selected number of averaged results is outside the available
range -see BFM #1 to #4
Averaging is normal.
(between 1 to 256)
b12 to b15 : Not used 
Non-
contact
analog
switch
CPU
System
ROM
Buffer
Memory
RAM
A/D
converter
PLC
Command
information
write and
data status
read
24V DC
Power Source
5V Power
Supply
POWER
LED
Photocoupler
±15V
CH1
CH2
CH3
CH4
A/D
LED
Cyclic switching
FX
2N
-4AD-TC Analog Block
DC/DC
converter
Gain and offset
values are
stored in the
EEPROM
Control
signals
Converted
data
24V
LED
FROM
TO
5V
Analog Input
M8002
Initial
Pulse
K2 K30 D2 K1
Y010
FNC78
FROM
K2030 D2 M0
FNC10
CMP
M8000
RUN
monitor
K2 K29 K4M10 K1
FNC78
FROM
M10
M8002 K2 K0 H3310 K1
FNC79
TO
Initial
Pulse
Error found
Specify the type of thermocouples.
H3310 R Block No.2 BFM#0
CH4 and CH3: not used
CH2: Type J(1)
CH1: Type K(0)
Block No.2 BFM #30 R (D2)
Identification code
When (K2030) = (D2), M1 = ON.
i.e. When identification code is K2030, M1 = ON.
This initial step checks that the special function block placed at position 2 is actually
an FX
2N
-4AD-TC, i.e. its unit identification number is 2030 (BFM #30). This step is
optional, but it provides a software check that the system has been configured
correctly.
Block No.2 BFM #29 R (K4M10)
Transfer the error status to (M25 to M10).
When error is found, M10 = ON
Represents b0 BFM #29
This step provides optional monitoring of the FX
2N
-4AD-TC Error Buffer Memory (#29).
If there is an Error on the FX
2N
-4AD-TC, bit b0 of BFM #29 will be set on. This can be
read by this program step, and output as a bit device in the PLC (Y010 in this example).
Additional Error devices can be output in a similar manner, e.g. b10 BFM #29 Digital
range error. (see below)
Y010
M8000 K2 K29 K4M10 K1
FNC78
FROM
M10
Y011
M20
Represents b0 BFM #29
Represents b10 BFM #29
9. DIAGNOSTICS
9.1 Preliminary checks
I. Check whether the input/output wiring and/or extension cables are properly connected on the FX2N-
4AD-TC analog special function block.
II. Check that the PLC system configuration limits have not been exceeded, i.e. the number of special
function blocks and the total system I/O are within the specified range.
III. Ensure that the correct operating range has been selected for the application.
IV. Check that there is no power overload on either the 5V or 24V power sources, remember the loading
on the main unit or a powered extension unit varies according to the number of extension blocks or
special function blocks connected.
V. Make sure that the main unit has been switched to RUN.
9.2 Error checking
If the FX2N-4AD-TC special function block does not seem to operate normally, check the following items.
• Check the status of the POWER LED.
Lit :The extension cable is properly connected.
Otherwise :Check the connection of the extension cable.
• Check the external wiring.
• Check the status of the “24V” LED (top right corner of the FX2N-4AD-TC).
Lit :FX2N-4AD-TC is ON, 24V DC power source is ON.
Otherwise :Possible 24V DC power failure, if ON possible FX2N-4AD-TC failure.
• Check the status of the “A/D” LED (top right corner of the FX2N-4AD-TC).
Lit :A/D conversion is proceeding normally.
Otherwise :Check buffer memory #29 (error status). If any bits (b0, b2, b3) are ON, then this is why
the A/D LED is OFF.
10.EMC CONSIDERATIONS
Electromagnetic compatibility or EMC must be considered before using the FX2N-4AD-TC.
Mitsubishi recommend that the thermocouple sensors used, should be fitted with a form of seild or
screening as protection against EMC noise.
If some form of cable protection is used, the “Shield” must be terminated at the terminals
as shown in chapter 2.
Because of the delicate nature of all analog signals, failure to take good EMC precautions could lead to
EMC noise induced errors; up to ±10% of actual values. This is an absolute worst case figure, users who
do take good precautions can expect operation within normal tolerances.
EMC considerations should include selection of good quality cables, good routing of those cables away
from potential noise sources.
Additionally it is recommended that signal averaging is used as this will reduce the effects of random
noise “spikes”.
M1 K2 K1 K4 K2
FNC79
TO
K2 K5 D0 K2
FNC78
FROM
P
K2 K29 K4M10 K1
FNC78
FROM
special
block No.2 FX
2N
-4AD-TC
BFM number result
destination No. of
words read
(K4) →(BFM #1), (K4) →(BFM #2)
Number of samples is changed to four on both CH1 and
CH2.
(BFM #5) →(D0), (BFM #6) →(D1)
Transfer the averaged temperature value in °C to the
data registers.
This step is the actual reading of the FX
2N
-4AD-TC input channels. It is essentially the
only program step which is needed. The "TO" instruction in this example, sets the input
channels, CH1 and CH2, to take the average reading of four samples.
The "FROM" instruction reads the average temperatures (BFM #5 and #6) for input
channels CH1 and CH2 of the FX
2N
-4AD-TC. If direct temperature readings are
required BFM #9 and #10 should be read instead, e.g.
SLD
Manual number: JY992D65501
Manual revision: B
Date : SEPTEMBER 2002

HEAD OFFICE : MITSUBISHI DENKI BLDG MARUNOUTI TOKYO 100-8310 TELEX : J24532 CABLE MELCO TOKYO
HIMEJI WORKS : 840, CHIYODA CHO, HIMEJI, JAPAN
6. ALLOCATION OF BUFFER MEMORIES (BFM)
6.1 Buffer memories
The FX2N-4AD-TC communicates
with the PLC via buffer memories.
BFMs #21 to #27 and #31 are
reserved.
All non reserved BFMs can be read
by the PLC using the FROM
instruction.
BFMs (buffer memories) marked
with an “*” can be written to, the
special function block using the TO
instruction.
1) Buffer Memory BFM #0: Thermocouple Type K or J selection mode
BFM #0 is used to select Type K or J thermocouples for each channel. Each digit of a 4 digit
hexadecimal number corresponds to one channel, the least significant digit being channel 1.
• A/D conversion time is 240ms per channel. When “3" (unused) is set for a channel, A/D conversion is
not executed for that channel, therefore, the total conversion time is decreased. In the above example,
the conversion time is as follows:
240ms (conversion time per channel) ×2channels (number of channels used) = 480ms (total
conversion time)
2) Buffer Memory BFMs #1 to #4: Number of temperature readings to be averaged
When the number of temperature readings to be averaged is specified for BFMs #1 to #4, the
averaged data is stored in BFMs #5 to #8 (°C) and #13 to #16 (°F). Only the range 1 to 256 is valid for
the number of temperature readings to be averaged. If a value outside of this range is entered, a
default value of 8 is used.
3) Buffer Memory BFMs #9 to #12 and #17 to #20: Present temperature
These BFMs store the present value of the input data. This value is stored in units of 0.1°C or 0.1°F,
but the resolution is only 0.4°C or 0.72°F for Type K and 0.3°C or 0.54°F for Type J.
6.2 Status Information
1) Buffer Memory BFM #28: Digital range error latch
BFM #29 b10(digital range error) is used to judge whether the measured temperature is within the
unit’s range.
BFM #28 latches the error status of each channel and can be used to check for thermocouple
disconnection.
Low : Latches ON when the temperature measurement data drops below the lowest
temperature limit.
High : Turns ON when the temperature measurement data rises above the highest
temperature limit, or when a thermocouple is disconnected.
When an error occurs the temperature data before the error is latched. If the measured value returns
to within valid limits the temperature data returns to normal operation. (Note: The error remains
latched in (BFM #28))
An error can be cleared by writing K0 to BFM #28 using the TO instruction or turning off the power.
b15 or b8 b7 b6 b5 b4 b3 b2 b1 b0
Not used High Low High Low High Low High Low
CH4 CH3 CH2 CH1
BFM CONTENTS
*#0 Thermocouple Type K or J selection mode.
At shipment: H0000
*# 1 - #4 CH1 to CH4 Averaged temperature reading to be
averaged (1 to 256) Default = 8
#5 - #8 CH1 to CH4 Averaged temperature in 0.1°C units
#9 - #12 CH1 to CH4 Present temperature in 0.1°C units
#13 - #16 CH1 to CH4 Averaged temperature in 0.1°F units
#17 - #20 CH1 to CH4 Present temperature in 0.1°F units
#21 - #27 Reserved
*#28 Digital range error latch
#29 Error status
#30 Identification code K2030
#31 Reserved
H 3 3 1 0CH1
CH2
CH3
CH4
0 = K type
1 = J type
3 = Not used
[ Example ]
2) Buffer Memory BFM #29: Error status
3) Identification Code Buffer Memory BFM #30
The identification code or ID number for this Special Block is read from buffer memory BFM #30 using
the FROM instruction. This number for the FX2N-4AD-TC unit is K2030. The PLC can use this facility in
its program to identify the special block before commencing data transfer to and from the special block.
7. SYSTEM BLOCK DIAGRAM
8. EXAMPLE PROGRAM
In the program shown below, the FX2N-4AD-TC occupies the position of special block number 2 (that is
the third closest block to the PLC). A Type K thermocouple is used on CH1 and a Type J on CH2. CH3 and
CH4 are not used. The averaging count is four. The averaged values in degrees C of input channels CH1
and CH2 are stored respectively in data registers D0 and D1.
Bit devices of BFM #29 ON OFF
b0 : Error When either b2 or b3 is ON A/D conversion is stopped for
the error channel No error
b1 : Not used 
b2 : Power source 24V DC power supply failure power supply normal
b3 : Hardware error A/D converter or other
hardware failure Hardware Normal
b4 to b9 : Not used 
b10 : Digital range error Digital output/analog input value is outside the specified
range. Digital output value is normal.
b11 : Averaging number error Selected number of averaged results is outside the available
range -see BFM #1 to #4
Averaging is normal.
(between 1 to 256)
b12 to b15 : Not used 
Non-
contact
analog
switch
CPU
System
ROM
Buffer
Memory
RAM
A/D
converter
PLC
Command
information
write and
data status
read
24V DC
Power Source
5V Power
Supply
POWER
LED
Photocoupler
±15V
CH1
CH2
CH3
CH4
A/D
LED
Cyclic switching
FX
2N
-4AD-TC Analog Block
DC/DC
converter
Gain and offset
values are
stored in the
EEPROM
Control
signals
Converted
data
24V
LED
FROM
TO
5V
Analog Input
M8002
Initial
Pulse
K2 K30 D2 K1
Y010
FNC78
FROM
K2030 D2 M0
FNC10
CMP
M8000
RUN
monitor
K2 K29 K4M10 K1
FNC78
FROM
M10
M8002 K2 K0 H3310 K1
FNC79
TO
Initial
Pulse
Error found
Specify the type of thermocouples.
H3310 R Block No.2 BFM#0
CH4 and CH3: not used
CH2: Type J(1)
CH1: Type K(0)
Block No.2 BFM #30 R (D2)
Identification code
When (K2030) = (D2), M1 = ON.
i.e. When identification code is K2030, M1 = ON.
This initial step checks that the special function block placed at position 2 is actually
an FX
2N
-4AD-TC, i.e. its unit identification number is 2030 (BFM #30). This step is
optional, but it provides a software check that the system has been configured
correctly.
Block No.2 BFM #29 R (K4M10)
Transfer the error status to (M25 to M10).
When error is found, M10 = ON
Represents b0 BFM #29
This step provides optional monitoring of the FX
2N
-4AD-TC Error Buffer Memory (#29).
If there is an Error on the FX
2N
-4AD-TC, bit b0 of BFM #29 will be set on. This can be
read by this program step, and output as a bit device in the PLC (Y010 in this example).
Additional Error devices can be output in a similar manner, e.g. b10 BFM #29 Digital
range error. (see below)
Y010
M8000 K2 K29 K4M10 K1
FNC78
FROM
M10
Y011
M20
Represents b0 BFM #29
Represents b10 BFM #29
9. DIAGNOSTICS
9.1 Preliminary checks
I. Check whether the input/output wiring and/or extension cables are properly connected on the FX2N-
4AD-TC analog special function block.
II. Check that the PLC system configuration limits have not been exceeded, i.e. the number of special
function blocks and the total system I/O are within the specified range.
III. Ensure that the correct operating range has been selected for the application.
IV. Check that there is no power overload on either the 5V or 24V power sources, remember the loading
on the main unit or a powered extension unit varies according to the number of extension blocks or
special function blocks connected.
V. Make sure that the main unit has been switched to RUN.
9.2 Error checking
If the FX2N-4AD-TC special function block does not seem to operate normally, check the following items.
• Check the status of the POWER LED.
Lit :The extension cable is properly connected.
Otherwise :Check the connection of the extension cable.
• Check the external wiring.
• Check the status of the “24V” LED (top right corner of the FX2N-4AD-TC).
Lit :FX2N-4AD-TC is ON, 24V DC power source is ON.
Otherwise :Possible 24V DC power failure, if ON possible FX2N-4AD-TC failure.
• Check the status of the “A/D” LED (top right corner of the FX2N-4AD-TC).
Lit :A/D conversion is proceeding normally.
Otherwise :Check buffer memory #29 (error status). If any bits (b0, b2, b3) are ON, then this is why
the A/D LED is OFF.
10.EMC CONSIDERATIONS
Electromagnetic compatibility or EMC must be considered before using the FX2N-4AD-TC.
Mitsubishi recommend that the thermocouple sensors used, should be fitted with a form of seild or
screening as protection against EMC noise.
If some form of cable protection is used, the “Shield” must be terminated at the terminals
as shown in chapter 2.
Because of the delicate nature of all analog signals, failure to take good EMC precautions could lead to
EMC noise induced errors; up to ±10% of actual values. This is an absolute worst case figure, users who
do take good precautions can expect operation within normal tolerances.
EMC considerations should include selection of good quality cables, good routing of those cables away
from potential noise sources.
Additionally it is recommended that signal averaging is used as this will reduce the effects of random
noise “spikes”.
M1 K2 K1 K4 K2
FNC79
TO
K2 K5 D0 K2
FNC78
FROM
P
K2 K29 K4M10 K1
FNC78
FROM
special
block No.2 FX
2N
-4AD-TC
BFM number result
destination No. of
words read
(K4) →(BFM #1), (K4) →(BFM #2)
Number of samples is changed to four on both CH1 and
CH2.
(BFM #5) →(D0), (BFM #6) →(D1)
Transfer the averaged temperature value in °C to the
data registers.
This step is the actual reading of the FX
2N
-4AD-TC input channels. It is essentially the
only program step which is needed. The "TO" instruction in this example, sets the input
channels, CH1 and CH2, to take the average reading of four samples.
The "FROM" instruction reads the average temperatures (BFM #5 and #6) for input
channels CH1 and CH2 of the FX
2N
-4AD-TC. If direct temperature readings are
required BFM #9 and #10 should be read instead, e.g.
SLD
Manual number: JY992D65501
Manual revision: B
Date : SEPTEMBER 2002

FX2N-4AD-TC SPECIAL FUNCTION BLOCK
USER’S GUIDE
JY992D65501B
This manual contains text, diagrams and explanations which will guide the reader in the correct
installation and operation of the FX2N-4AD-TC special function block and should be read and understood
before attempting to install or use the unit.
Further information can be found in the FX PROGRAMMING MANUAL(ΙΙ) and FX0N/FX1N/FX2N/FX2NC
SERIES HARDWARE MANUAL.
Guidelines for the Safety of the User and Protection of the FX2N-4AD-TC
special function block.
This manual should be used by trained and competent personnel. The definition of such a person or
persons is as follows:
a) Any engineer using the product associated with this manual, should be of a competent nature,
trained and qualified to the local and national standards. These engineers should be fully aware of
all aspects of safety with regards to automated equipment.
b) Any commissioning or service engineer must be of a competent nature, trained and qualified to
the local and national standards.
c) All operators of the completed equipment should be trained to use this product in a safe and
coordinated manner in compliance to established safety practices.
Note: The term ‘completed equipment’ refers to a third party constructed device which contains or uses
the product associated with this manual.
Notes on the Symbols Used in this Manual
At various times throughout this manual certain symbols will be used to highlight points of information
which are intended to ensure the users personal safety and protect the integrity of equipment.
1) Indicates that the identified danger WILL cause physical and property damage.
2) Indicates that the identified danger could POSSIBLY cause physical and property
damage.
• Under no circumstances will Mitsubishi Electric be liable or responsible for any consequential damage
that may arise as a result of the installation or use of this equipment.
• All examples and diagrams shown in this manual are intended only as an aid to understanding the
text, not to guarantee operation. Mitsubishi Electric will accept no responsibility for the actual use of
the product based on these illustrative examples.
• Owing to the very great variety in possible applications for this equipment, you must satisfy yourself as
to its suitability for your own specific application.
1. INTRODUCTION
• The FX2N-4AD-TC analog block amplifies the signal from four thermocouple sensors (Type K or J) and
converts the data into 12 bit reading’s stored in the main unit. Both Centigrade (°C) and Fahrenheit
(°F) can be read.
Reading resolution is 0.4°C/0.72°F of Type K and 0.3°C/0.54°F of Type J.
• The FX2N-4AD-TC can connected to the FX0N, FX1N, FX2N and the FX2NC series Programmable
Controllers (PLC).
• All data transfers and parameter settings are adjusted via software control of the FX2N-4AD-TC; by
use of the TO/FROM applied instructions in the PLC.
• The FX2N-4AD-TC occupies 8 I/O points on the PLC expansion bus. The 8 I/O points can be allocated
from either inputs or outputs. The FX2N-4AD-TC draws 40mA from the 5V rail of the main unit or
powered extension unit.
• Thermocouples with the following specifications can be used: Type K (JIS 1602-1981)
Type J (JIS 1602-1981)
2. EXTERNAL DIMENSIONS
3. CONNECTION WITH PLC
3.1 Connection with PLC
1) Up to 4 FX2N-4AD-TC units can connect to the FX0N series PLC, up to 5 for FX1N, up to 8 for FX2N or,
up to 4 for an FX2NC series PLC, all with powered extension units.
However the following limitation exists when the undermentioned special function blocks are
connected.
FX2N: Main unit and powered extension units of 32 I/O points or less. Current consumption available
for the undermentioned special function blocks ≤190mA
FX2N: Main unit and powered extension units of 48 I/O points or more. Current consumption
available for the undermentioned special function blocks ≤300mA
FX2NC:Up to 4 undermentioned special function blocks can be connected regardless of the system I/O.
When using an FX2NC an FX2NC-CNV-IF is required.
FX0N/1N:Main unit and powered extension units. Up to 2 undermentioned special function blocks can
be connected regardless of the system I/O.
2) Each block occupies 8 I/O points (The 8 points can be allocated from either inputs or outputs).
3) FX2N-4AD-TC consumes 40mA from the 5V DC bus.
The total 5V consumption of all special function blocks connected to a main unit or extension unit
must not exceed the 5V source capacity of the system.
4) The FX2N-4AD-TC and main unit are connected by a cable on the right of the main unit.
3.2 Special function block numbers
Other special units of blocks that use FROM/TO commands, such as analog input blocks, analog output
blocks and high-speed counter blocks, can be directly connected to the main unit of the PLC or to the right
side of other extension blocks or units.
4. WIRING
4.1 Wiring
*1: The compensating cables that can be used for
connecting with the thermocouple are the following.
Type K: KX-G, KX-GS, KX-H, KX-HS,WX-G,WX-H,VX-G
Type J: JX-G, JX-H
For every 10Ωof line resistance, the compensating
cable will indicate a temperature 0.12°C higher than
actual.
Check the line resistance before using. Long
compensating cables are more prone to noise
interference, therefore a short (less than 100m)
compensating cable is recommended.
Unused channels should have a wire link connected
between the + and - terminals to prevent an errors being
detected on that channel.
*2: If there is excessive electrical noise, connect the SLD
terminal to the ground terminal on the unit.
*3: Connect the ground terminals of the FX2N-4AD-TC unit and the main unit. Use grounding on the main
unit.
*4: The 24V DC built-in supply of the PLC may be used as the power supply.
P O W E R
2 4 V
A / D
C H 4C H 3
C H 1
2 4 +
2 4 -
L +
L +
F X
2 N
- 4 A D - T C
L - L -
L +
L -
S L D
C H 1
2 4 +
2 4 - L -
C H 2
L -
L +
L +
4 ( 0 . 1 6 )
4 ( 0 . 1 6 )
5 5 ( 2 . 1 7 )
8 0 ( 3 . 1 5 )
0 ( 3 . 5 4 )
5 5 ( 2 . 1 7 )
8 7 ( 3 . 4 3 )
( 0 . 3 5 )
S L D
S L D
S L D
S L D
T e r m i n a l s c r e w s M 3 ( 0 . 1 2 )
2 4 V
L E D
A / D
L E D
D I N r a i l
m o u n t i n g s l o t
3 5 m m ( 1 . 3 8 )
M o u n t i n g h o l e s
4 . 5 m m ( 0 . 1 8 ) d i a .
E x t e n s i o n c a b l e
a n d c o n n e c t o r
Weight: Approx. 0.3 kg (0.66 lbs) Dimensions: mm (inches)
Accessories: Self adhesive labels for special function block number identification
F X - 1 6 E X
X 0 0 0 - X 0 2 7
Y 0 0 0 - Y 0 2 7
X 0 3 0
- X 0 4 7
2 N
F X - 4 8 M R - E S / U L 2 N
F X - 4 A D 2 N
N o . 2
2 N
F X - 4 A D - T C
X 0 5 0 - X 0 6 7
Y 0 3 0 - Y 0 4 7
2 N
F X - 3 2 E R
2 N
F X - 4 D A
F X - 4 8 M R - E S / U L
2 N
P O W E R
A / D
2 4 V
F X - 4 A D
2 N
P O W E R
D / A
2 4 V
F X - 4 D A
2 N
N o . 1
N o . 0
P O W E R
24V
A / D
S p e c i a l b l o c k S p e c i a l b l o c k S p e c i a l b l o c k
X 0
X 5
72 4 5 61 30
1 61 1 1 51 4 1 71 0 1 2 1 3
1 4 1 71 51 0 1 2 1 3
72 4 5 61 30
1 61 1
O U T
I N
LX 1 1 X 1 3 X 1 5 X 1 7
X 6 X 1 0 X 1 2 X 1 4 X 1 6
24+
N
C O M X 4
X 7
C O M 4
C O M 2
Y 4
Y 5
Y 6
Y 7 C O M 3
Y 1 0
Y 1 1
Y 1 2
Y 1 3
C O M 1
Y 0
Y 1
Y 2
Y 3
Y 1 4
Y 1 5
Y 1 6
Y 1 7
X 3
X 2
X 1
P O W E R
76 2 72 0 2 2 2 3 2 4 2 5 2 62 1
1 6 1 7
1 4 1 71 51 0 1 2 1 3
72 4 5 61 30 2 72 0 2 2 2 3 2 4 2 5 2 62 1
1 61 1
I N
L X 5 X 7 X 1 3 X 1 5 X 1 7 X 2 1 X 2 3 X 2 5
X 4 X 6 X 1 0 X 1 4 X 1 6 X 2 0 X 2 2 X 2 4
2 4 +N
C O M X 0
X 1
X 2
C O M 4
Y 2 4
Y 2 5
C O M 5
Y 2 7C O M 2
Y 4
Y 5
Y 6
Y 7 C O M 3
Y 1 0
Y 1 3C O M 1
Y 0 Y 2
Y 3
Y 1 4
Y 1 5
Y 2 0
Y 2 1
Y 2 2
Y 2 3
Y 2 6
P O W E R
T . V
C P U . E
P R O G . E
Connection example
Thermocouple 1
shielded CH1 3K
:
L+
24+
24-
DC/DC
converter AG
+15V
-15V
PLC
Extension cable
Grounding
(100
:
or less)
3
4
24VDC±10% 50mA 2
FX2N-4AD-TC
Analog Input Block
L-
CH1
SLD
Thermocouple 1
shielded CH4 L+
L-
SLD
3K
:
Temperature
compensation
circuit
CH4
4.2 Using crimp terminations
• Use crimp terminals as indicated on the left.
• Secure the terminal using a tightening torque of between 5 and 8
kg⋅cm.
• Wire only to the module terminals discussed in this manual. Leave all
others vacant.
5. SPECIFICATIONS
5.1 Environmental specification
5.2 Power supply specification
5.3 Performance specification
Analog Inputs
Miscellaneous
Note: Earth-tipped thermocouples are not suitable for use with this unit.
5.4 Installation location
This unit measures temperature according to the temperature difference between the temperature
measurement part (themocouple) and the terminal block. If this unit is installed at a place where the
temperature of the terminal block varies rapidly, a measuring error may occur. For this reason, the unit
should be installed at a place free from excessive temperature variation.
Item Specification
Environmental specifications Same as those for the main unit
Dielectric withstand voltage 500V AC, 1min (between all terminals and ground)
Item Specification
Analog circuits 24V DC ± 10%, 60mA
Digital circuits 5V DC, 40mA (internal power supply from the main unit)
Item Centigrade (°
°°
°C) Fahrenheit (°
°°
°F)
Both °C and °F are available by reading the appropriate buffer memory (BFM).
Input signal Thermocouple: Type K or J (either can be used for each channel), 4 channels, JIS
1602-1981
Rated temperature
range Type K -100°C to +1,200°C Type K -148°F to +2,192°F
Type J -100°C to +600°C Type J -148°F to +1,112°F
Digital output
12 bit conversion stored in 16 bit 2’s complement form
Type K -1,000 to 12,000 Type K -148°F to +2,192°F
Type J -1,000 to 6,000 Type J -148°F to +1,112°F
Resolution Type K 0.4°C Type K 0.72°F
Type J 0.3°C Type J 0.54°F
Overall accuracy
Calibration point ± (0.5% full scale +1°C) Freezing point of pure water 0°C / 32°F
Conversion speed (240ms ± 2%) ×4 channels (unused channels are not converted)
Item Centigrade (°
°°
°C) Fahrenheit (°
°°
°F)
Conversion Characteristics
Readings given at calibration
reference point 0°C/32°F (0/320)
respectively.
(subject to the overall accuracy)
Item Specification
Isolation Photo-coupler isolation between analog and digital circuits. DC/DC converter isolation of power from main unit.
No isolation between analog channels.
Number of occupied I/O points The block occupies 8 I/O points
(can be either inputs or outputs)
l e s s t h a n
6 . 2 m m ( 0 . 2 4 )
U s e M 3 ( 0 . 1 2 )
l e s s t h a n
6 . 2 m m ( 0 . 2 4 )
+6,000
-100°C
-1,000 +1,200°C
+12,000
(Type K)
(Type J)
+600°C (Type K)(Type J) -1,480 +2,192°F
+21,920
(Type K)
(Type J)
+1,112°F (Type K)(Type J)
+11,120
-148°F

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6. ALLOCATION OF BUFFER MEMORIES (BFM)
6.1 Buffer memories
The FX2N-4AD-TC communicates
with the PLC via buffer memories.
BFMs #21 to #27 and #31 are
reserved.
All non reserved BFMs can be read
by the PLC using the FROM
instruction.
BFMs (buffer memories) marked
with an “*” can be written to, the
special function block using the TO
instruction.
1) Buffer Memory BFM #0: Thermocouple Type K or J selection mode
BFM #0 is used to select Type K or J thermocouples for each channel. Each digit of a 4 digit
hexadecimal number corresponds to one channel, the least significant digit being channel 1.
• A/D conversion time is 240ms per channel. When “3" (unused) is set for a channel, A/D conversion is
not executed for that channel, therefore, the total conversion time is decreased. In the above example,
the conversion time is as follows:
240ms (conversion time per channel) ×2channels (number of channels used) = 480ms (total
conversion time)
2) Buffer Memory BFMs #1 to #4: Number of temperature readings to be averaged
When the number of temperature readings to be averaged is specified for BFMs #1 to #4, the
averaged data is stored in BFMs #5 to #8 (°C) and #13 to #16 (°F). Only the range 1 to 256 is valid for
the number of temperature readings to be averaged. If a value outside of this range is entered, a
default value of 8 is used.
3) Buffer Memory BFMs #9 to #12 and #17 to #20: Present temperature
These BFMs store the present value of the input data. This value is stored in units of 0.1°C or 0.1°F,
but the resolution is only 0.4°C or 0.72°F for Type K and 0.3°C or 0.54°F for Type J.
6.2 Status Information
1) Buffer Memory BFM #28: Digital range error latch
BFM #29 b10(digital range error) is used to judge whether the measured temperature is within the
unit’s range.
BFM #28 latches the error status of each channel and can be used to check for thermocouple
disconnection.
Low : Latches ON when the temperature measurement data drops below the lowest
temperature limit.
High : Turns ON when the temperature measurement data rises above the highest
temperature limit, or when a thermocouple is disconnected.
When an error occurs the temperature data before the error is latched. If the measured value returns
to within valid limits the temperature data returns to normal operation. (Note: The error remains
latched in (BFM #28))
An error can be cleared by writing K0 to BFM #28 using the TO instruction or turning off the power.
b15 or b8 b7 b6 b5 b4 b3 b2 b1 b0
Not used High Low High Low High Low High Low
CH4 CH3 CH2 CH1
BFM CONTENTS
*#0 Thermocouple Type K or J selection mode.
At shipment: H0000
*# 1 - #4 CH1 to CH4 Averaged temperature reading to be
averaged (1 to 256) Default = 8
#5 - #8 CH1 to CH4 Averaged temperature in 0.1°C units
#9 - #12 CH1 to CH4 Present temperature in 0.1°C units
#13 - #16 CH1 to CH4 Averaged temperature in 0.1°F units
#17 - #20 CH1 to CH4 Present temperature in 0.1°F units
#21 - #27 Reserved
*#28 Digital range error latch
#29 Error status
#30 Identification code K2030
#31 Reserved
H 3 3 1 0CH1
CH2
CH3
CH4
0 = K type
1 = J type
3 = Not used
[ Example ]
2) Buffer Memory BFM #29: Error status
3) Identification Code Buffer Memory BFM #30
The identification code or ID number for this Special Block is read from buffer memory BFM #30 using
the FROM instruction. This number for the FX2N-4AD-TC unit is K2030. The PLC can use this facility in
its program to identify the special block before commencing data transfer to and from the special block.
7. SYSTEM BLOCK DIAGRAM
8. EXAMPLE PROGRAM
In the program shown below, the FX2N-4AD-TC occupies the position of special block number 2 (that is
the third closest block to the PLC). A Type K thermocouple is used on CH1 and a Type J on CH2. CH3 and
CH4 are not used. The averaging count is four. The averaged values in degrees C of input channels CH1
and CH2 are stored respectively in data registers D0 and D1.
Bit devices of BFM #29 ON OFF
b0 : Error When either b2 or b3 is ON A/D conversion is stopped for
the error channel No error
b1 : Not used 
b2 : Power source 24V DC power supply failure power supply normal
b3 : Hardware error A/D converter or other
hardware failure Hardware Normal
b4 to b9 : Not used 
b10 : Digital range error Digital output/analog input value is outside the specified
range. Digital output value is normal.
b11 : Averaging number error Selected number of averaged results is outside the available
range -see BFM #1 to #4
Averaging is normal.
(between 1 to 256)
b12 to b15 : Not used 
Non-
contact
analog
switch
CPU
System
ROM
Buffer
Memory
RAM
A/D
converter
PLC
Command
information
write and
data status
read
24V DC
Power Source
5V Power
Supply
POWER
LED
Photocoupler
±15V
CH1
CH2
CH3
CH4
A/D
LED
Cyclic switching
FX
2N
-4AD-TC Analog Block
DC/DC
converter
Gain and offset
values are
stored in the
EEPROM
Control
signals
Converted
data
24V
LED
FROM
TO
5V
Analog Input
M8002
Initial
Pulse
K2 K30 D2 K1
Y010
FNC78
FROM
K2030 D2 M0
FNC10
CMP
M8000
RUN
monitor
K2 K29 K4M10 K1
FNC78
FROM
M10
M8002 K2 K0 H3310 K1
FNC79
TO
Initial
Pulse
Error found
Specify the type of thermocouples.
H3310 R Block No.2 BFM#0
CH4 and CH3: not used
CH2: Type J(1)
CH1: Type K(0)
Block No.2 BFM #30 R (D2)
Identification code
When (K2030) = (D2), M1 = ON.
i.e. When identification code is K2030, M1 = ON.
This initial step checks that the special function block placed at position 2 is actually
an FX
2N
-4AD-TC, i.e. its unit identification number is 2030 (BFM #30). This step is
optional, but it provides a software check that the system has been configured
correctly.
Block No.2 BFM #29 R (K4M10)
Transfer the error status to (M25 to M10).
When error is found, M10 = ON
Represents b0 BFM #29
This step provides optional monitoring of the FX
2N
-4AD-TC Error Buffer Memory (#29).
If there is an Error on the FX
2N
-4AD-TC, bit b0 of BFM #29 will be set on. This can be
read by this program step, and output as a bit device in the PLC (Y010 in this example).
Additional Error devices can be output in a similar manner, e.g. b10 BFM #29 Digital
range error. (see below)
Y010
M8000 K2 K29 K4M10 K1
FNC78
FROM
M10
Y011
M20
Represents b0 BFM #29
Represents b10 BFM #29
9. DIAGNOSTICS
9.1 Preliminary checks
I. Check whether the input/output wiring and/or extension cables are properly connected on the FX2N-
4AD-TC analog special function block.
II. Check that the PLC system configuration limits have not been exceeded, i.e. the number of special
function blocks and the total system I/O are within the specified range.
III. Ensure that the correct operating range has been selected for the application.
IV. Check that there is no power overload on either the 5V or 24V power sources, remember the loading
on the main unit or a powered extension unit varies according to the number of extension blocks or
special function blocks connected.
V. Make sure that the main unit has been switched to RUN.
9.2 Error checking
If the FX2N-4AD-TC special function block does not seem to operate normally, check the following items.
• Check the status of the POWER LED.
Lit :The extension cable is properly connected.
Otherwise :Check the connection of the extension cable.
• Check the external wiring.
• Check the status of the “24V” LED (top right corner of the FX2N-4AD-TC).
Lit :FX2N-4AD-TC is ON, 24V DC power source is ON.
Otherwise :Possible 24V DC power failure, if ON possible FX2N-4AD-TC failure.
• Check the status of the “A/D” LED (top right corner of the FX2N-4AD-TC).
Lit :A/D conversion is proceeding normally.
Otherwise :Check buffer memory #29 (error status). If any bits (b0, b2, b3) are ON, then this is why
the A/D LED is OFF.
10.EMC CONSIDERATIONS
Electromagnetic compatibility or EMC must be considered before using the FX2N-4AD-TC.
Mitsubishi recommend that the thermocouple sensors used, should be fitted with a form of seild or
screening as protection against EMC noise.
If some form of cable protection is used, the “Shield” must be terminated at the terminals
as shown in chapter 2.
Because of the delicate nature of all analog signals, failure to take good EMC precautions could lead to
EMC noise induced errors; up to ±10% of actual values. This is an absolute worst case figure, users who
do take good precautions can expect operation within normal tolerances.
EMC considerations should include selection of good quality cables, good routing of those cables away
from potential noise sources.
Additionally it is recommended that signal averaging is used as this will reduce the effects of random
noise “spikes”.
M1 K2 K1 K4 K2
FNC79
TO
K2 K5 D0 K2
FNC78
FROM
P
K2 K29 K4M10 K1
FNC78
FROM
special
block No.2 FX
2N
-4AD-TC
BFM number result
destination No. of
words read
(K4) →(BFM #1), (K4) →(BFM #2)
Number of samples is changed to four on both CH1 and
CH2.
(BFM #5) →(D0), (BFM #6) →(D1)
Transfer the averaged temperature value in °C to the
data registers.
This step is the actual reading of the FX
2N
-4AD-TC input channels. It is essentially the
only program step which is needed. The "TO" instruction in this example, sets the input
channels, CH1 and CH2, to take the average reading of four samples.
The "FROM" instruction reads the average temperatures (BFM #5 and #6) for input
channels CH1 and CH2 of the FX
2N
-4AD-TC. If direct temperature readings are
required BFM #9 and #10 should be read instead, e.g.
SLD
Manual number: JY992D65501
Manual revision: B
Date : SEPTEMBER 2002