MG LTWT User manual

EM-3355 Rev.6 P. 1 / 4
MG CO., LTD. www.mgco.jp
5-2-55 Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
INSTRUCTION MANUAL
BEFORE USE ....
Thank you for choosing us. Before use, please check con-
tents of the package you received as outlined below.
If you have any problems or questions with the product,
please contact our sales office or representatives.
■PACKAGE INCLUDES:
Watt transducer ..................................................................(1)
■MODEL NO.
Confirm Model No. marking on the product to be exactly
what you ordered.
■INSTRUCTION MANUAL
This manual describes necessary points of caution when
you use this product, including installation, connection and
basic maintenance procedures.
POINTS OF CAUTION
■CONFORMITY WITH EU DIRECTIVES
• This equipment is suitable for Pollution Degree 2, Meas-
urement Category II (input, transient voltage 4000V)
and Installation Category II (auxiliary power, transient
voltage 2500V). Reinforced insulation (signal input to
output or auxiliary power input: 550V, output to auxiliary
power input 300V) are maintained. Prior to installation,
check that the insulation class of this unit satisfies the
system requirements.
• Altitude up to 2000 meters.
• The equipment must be mounted inside a panel.
• The equipment must be installed such that appropriate
clearance and creepage distances are maintained to con-
form to CE requirements. Failure to observe these re-
quirements may invalidate the CE conformance.
• The actual installation environments such as panel con-
figurations, connected devices, connected wires, may af-
fect the protection level of this unit when it is integrated
in a panel system. The user may have to review the CE
requirements in regard to the whole system and employ
additional protective measures to ensure the CE conform-
ity.
• Install lightning surge protectors for those wires connect-
ed to remote locations.
■AUXILIARY POWER SUPPLY RATING & OPERATIONAL RANGE
• Locate the auxiliary power supply rating marked on the
product and confirm its operational range as indicated
below:
100 – 120V AC rating: 85 – 132V, 47 – 66 Hz, approx. 2VA
200 – 240V AC rating: 170 – 264V, 47 – 66 Hz, approx. 2VA
24V, 48V DC rating: Rating ±10%, approx. 2W
110V DC rating: 85 – 150V, approx. 2W
■GENERAL PRECAUTIONS
• Before you remove or mount the unit, turn off the power
supply and input signal for safety.
■ENVIRONMENT
• Indoor use.
• When heavy dust or metal particles are present in the
air, install the unit inside proper housing with sufficient
ventilation.
• Do not install the unit where it is subjected to continuous
vibration. Do not subject the unit to physical impact.
• Environmental temperature must be within -10 to +55°C
(14 to 131°F) with relative humidity within 30 to 85% RH
in order to ensure adequate life span and operation.
■WIRING
• Do not install cables close to noise sources (relay drive
cable, high frequency line, etc.).
• Do not bind these cables together with those in which
noises are present. Do not install them in the same duct.
■AND ....
• The unit is designed to function as soon as power is sup-
plied, however, a warm up for 10 minutes is required for
satisfying complete performance described in the data
sheet.
COMPONENT IDENTIFICATION
Span Adjustment
Zero Adjustment
Connection
Diagram
Body
Specifications
INSTALLATION
■DIN RAIL MOUNTING
Set the unit so that its DIN rail adaptor is at the bottom.
Hang the upper hook at the rear side of the unit on the DIN
rail and push in the lower. When removing the unit, push
down the DIN rail adaptor utilizing a minus screwdriver
and pull.
DIN Rail
35mm wide
Spring Loaded
DIN Rail Adaptor
■WALL MOUNTING
Refer to “EXTERNAL DIMENSIONS.”
WATT TRANSDUCER MODEL LTWT

LTWT
EM-3355 Rev.6 P. 2 / 4
MG CO., LTD. www.mgco.jp
5-2-55 Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
TERMINAL CONNECTIONS
Connect the unit as in the diagram below or refer to the connection diagram on the side of the unit.
■EXTERNAL DIMENSIONS unit: mm (inch)
1 2 3 4 5 6
11 12 13 14 15 16
789 10
54 (2.13)
72 (2.83) [4 (.16)]143 (5.63)
3
(.12)
DIN RAIL
35mm wide
8 (.31)
2–M4 MTG HOLE
98 (3.86) 80 (3.15)
111 (4.37)
16–M4 SCREW
TERMINAL COVER (option /T)
10 (.39)
• When mounting, no extra space is needed between units.

LTWT
EM-3355 Rev.6 P. 3 / 4
MG CO., LTD. www.mgco.jp
5-2-55 Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
■CONNECTION DIAGRAM
LOAD
+
–
123
SOURCE
P2V
P1U
v
u
FUSE VT
Vv
P3
Uu
k
l
CT
L
K
1L
1S
3L
3S
k
l
L
K
7
9
8
13
14
1
5
6
2
PULSE OUTPUT
+
–
11
12
DC OUTPUT
■ 3-PHASE/3-WIRE ■ SINGLE-PHASE/2-WIRE
LOAD
12
SOURCE
P2V
P1U
v
u
FUSE VT
k
l
CT
L
K
1L
1S
+
–
7
8
13
14
1
2
PULSE OUTPUT
■ SINGLE-PHASE/3-WIRE
LOAD
1N2
SOURCE
P0V
P1U
v
u
FUSE VT
Vv
P2
Uu
k
l
CT
L
K
1L
1S
2L
2S
k
l
L
K
+
–
7
9
8
13
14
1
5
6
2
PULSE OUTPUT
16
* The transducer can be powered from the input voltage
when the voltage is sufficiently stable and meets within
the range of auxiliary power supply of the unit specified
in the data sheet/instruction manual.
LOAD
1N23
SOURCE
P2
V
P1U
v
u
FUSE VT
Vv
P3
Uu
Vv
P0
Uu
k
l
CT
L
K
1L
1S
2L
2S
3L
3S
k
l
L
K
k
l
L
K
+
–
13
14
PULSE OUTPUT
16
7
8
9
10
1
2
3
4
5
6
■ 3-PHASE/4-WIRE
16
+
–
11
12
DC OUTPUT
+
–
11
12
DC OUTPUT
+
–
11
12
DC OUTPUT
15
16
U(+)
V(–)
AUXILIARY
POWER
■ Open Collector
Pulse Output Connection Example
13
14
+
–
*
15
U(+)
V(–)
AUXILIARY
POWER
*
15
U(+)
V(–)
AUXILIARY
POWER
*
15
U(+)
V(–)
AUXILIARY
POWER
*

LTWT
EM-3355 Rev.6 P. 4 / 4
MG CO., LTD. www.mgco.jp
5-2-55 Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
WIRING INSTRUCTIONS
■SCREW TERMINAL
Torque: 1.2 N·m
CHECKING
1) Terminal wiring: Check that all cables are correctly con-
nected according to the connection diagram.
2) Auxiliary power input voltage: Check voltage across the
terminal 15 – 16 with a multimeter.
3) Input: Calculate the calibration range and check that the
result is within the usable range.
Calibration Range [W] = Measuring Wattage
(VT Ratio) × (CT Ratio)
4) DC Output: Check that the load resistance meets the
described specifications.
5) Totalizing pulse output: Check that the load connected to
the open collector output is within 35V DC @100mA.
ADJUSTMENT PROCEDURE
This unit is calibrated at the factory to meet the ordered
specifications, therefore you usually do not need any cali-
bration.
For matching the signal to a receiving instrument or in case
of regular calibration, adjust the output as explained in the
following.
■HOW TO CALIBRATE THE OUTPUT SIGNAL
Use a signal source and measuring instruments of suffi-
cient accuracy level. Turn the auxiliary power supply on
and warm up for more than 10 minutes.
1) ZERO: Apply 0% input and adjust output to 0%.
2) SPAN: Apply 100% input and adjust output to 100%.
3) Check ZERO adjustment again with 0% input.
4) When ZERO value is changed, repeat the above proce-
dure 1) – 3).
MAINTENANCE
Regular calibration procedure is explained below:
■CALIBRATION
Warm up the unit for at least 10 minutes. Apply 0%, 25%,
50%, 75% and 100% input signal. Check that the output
signal for the respective input signal remains within accu-
racy described in the data sheet. When the output is out of
tolerance, recalibrate the unit according to the “ADJUST-
MENT PROCEDURE” explained earlier.
LIGHTNING SURGE PROTECTION
We offer a series of lightning surge protector for protec-
tion against induced lightning surges. Please contact us to
choose appropriate models.