Datcon DT4240 Series User manual

DT4240 xx xx xx xx
AC Voltage Meter
Operating Instructions

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Contents
1. About this document .....................................................4
1.1. Function ................................................................................... 4
1.2. Target group............................................................................. 4
1.3. Symbolism used....................................................................... 4
2. For your safety ...............................................................5
2.1. Authorized personnel ............................................................... 5
2.2. Appropriate use........................................................................ 5
2.3. Warning about misuse ............................................................. 5
2.4. General safety instructions....................................................... 5
2.5. CE conformity........................................................................... 5
2.6. Environmental instructions ....................................................... 5
3. Product description .......................................................6
3.1. Delivery configuration............................................................... 6
3.2. Type designation...................................................................... 6
3.3. Principle of operation ............................................................... 7
3.4. Adjustment ............................................................................... 8
3.5. Display, indicators .................................................................... 9
3.6. Storage and transport .............................................................. 9
4. Mounting.......................................................................10
4.1. General instructions ............................................................... 10
4.2. Main dimensions of the instrument ........................................ 10
4.3. Mounting ................................................................................ 11
5. Connecting ...................................................................13
5.1. Preparing the connection ....................................................... 13
5.2. Connecting the mains ............................................................ 14
5.3. Connecting the input .............................................................. 15
5.4. Connecting the limit relay outputs (option)............................. 16
5.5. Connecting the analogue output (option)............................... 17
5.6. Connecting the RS232 Modbus communication output
(option). ......................................................................................... 18
5.7. Connecting the RS485 Modbus communication output
(option). ......................................................................................... 19

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6. Display and manual controls ......................................21
6.1. The first start-up ..................................................................... 21
6.2. Characters and mnemonics appearing on the display ........... 22
6.3. Manual controls, display, indicators ....................................... 25
7. Setting-up .....................................................................28
7.1. Typing the code (password) in ............................................... 28
7.2. The menu structure ................................................................ 30
7.3. Display brightness (01. menu item)........................................ 31
7.4. Voltage transformer ratio (IX) (03. menu item)....................... 32
7.5. Leading zero(s) enable / disable (06. menu item).................. 33
7.6. The number of averaged measurements (08. menu item)..... 34
7.7. Display refresh time (09. menu item) ..................................... 36
7.8. Setting limit outputs (10., 11. menu item)............................... 37
7.9. Limit output state display mode (12. menu item) ................... 43
7.10. Clear minimum and maximum values (13. menu item)........ 45
7.11. Analoge output signal setting (14. menu item)..................... 46
7.12. Assignment analog output low value to display value
(scaling) (15. menu item) .............................................................. 47
7.13. Assignment analog output high value to display value
(scaling) (16. menu item) .............................................................. 49
7.14. MODBUS communication settings (17. menu item)............. 51
7.15. Tests (18. menu item) .......................................................... 54
7.16. Changing the user code (19. menu item)............................. 57
7.17. Changing the supervisor code (20. menu item) ................... 59
7.18. Resetting the default settings (21. menu item)..................... 61
8. Fault rectification .........................................................62
8.1. Fault finding............................................................................ 62
8.2. Repairing................................................................................ 62
9. Dismounting .................................................................63
9.1. Dismounting procedure .......................................................... 63
9.2. Disposal ................................................................................. 63
10. Appendix.....................................................................64
10.1. Technical specifications ....................................................... 64
10.2. Application example ............................................................. 68
10.3. Setting up the instrument (example) .................................... 72
10.4. MODBUS settings ................................................................ 73

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1. About this document
1.1. Function
This operating instructions manual has all the information
you need for quick set-up and safe operation of
DT4240 xx xx xx xx.
Please read this manual before you start setup.
1.2. Target group
This operating instructions manual is directed to trained
personnel. The contents of this manual should be made
available to these personnel and put into practice by them.
1.3. Symbolism used
Information, tip, note
This symbol indicates helpful additional information.
Caution, warning, danger
This symbol informs you of a dangerous situation that could
occur. Ignoring this cautionary note can impair the person
and/or the instrument.
•List
The dot set in front indicates a list with no implied sequence.
1
Sequence
Numbers set in front indicate successive steps in a
procedure.
/
Parting
Parting set in between the elements of a list.
It’s meaning: only one element can be choosen from the list.

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2. For your safety
2.1. Authorized personnel
All operations described in this operating instructions
manual must be carried out only by trained and authorized
specialist personnel. For safety and warranty reasons, any
internal work on the instruments must be carried out only by
DATCON personnel.
2.2. Appropriate use
A DT4240 xx xx xx xx AC Voltage Meter measure AC
voltage in 0-125 V / 0-250 V / 0-450 V ranges.
Detailed information on the application range of the
instrument is available in chapter „Product description”.
2.3. Warning about misuse
Inappropriate or incorrect use of the instrument can give rise
to application-specific hazards, or damage to system
components through incorrect mounting or adjustment.
2.4. General safety instructions
The DT4240 xx xx xx xx is a high-tech instrument requiring
the strict observance of standard regulations and
guidelines. The user must take note of the safety
instructions in this operating instructions manual, the
country-specific installation standard as well as all prevailing
safety regulations and accident prevention rules.
2.5. CE conformity
A DT4240 xx xx xx xx is in conformity with the provisions of
the following standards:
MSZ EN 61326-1 (EMC)
2.6. Environmental instructions
Protection of the environment is one of our most important
duties.
Please take note of the instructions written in the following
chapters:
•Chapter 3.4. Storage and transport
•Chapter 9.2. Disposal

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3. Product description
3.1. Delivery configuration
The scope of delivery encompasses:
•DT4240 xx xx xx xx
•1 pc panel sealing (1)
•2 pc mounting clamps (enclosed in a nylon bag)
•1 pc 4 element plug in terminal (analogue or
communication option) (2)
•documentation:
this operating instructions manual
certification
warranty
Delivered items
3.2. Type designation

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3.3. Principle of operation
Area of application The DT4240 xx xx xx xx AC Voltage Meter enable
0-125 VAC / 0-250 VAC / 0-450 VAC voltage ranges to be
displayed on the control panel. Large 14.2 mm height LED
display make process value easily visible at a distance. The
displayed value is proportional to the True RMS value of the
input voltage.
Easy on-site configuration through the front panel
membrane keypad is a major advantage of the
microcontroller-based technology. The configuration
parameters: input range, signal filtering, output scaling,
display refresh rate, limit modes, limit values, etc. are stored
in EEPROM. The settings are protected by a two-level
password against unauthorized manipulation.
Options:
•Two normally open relay contacts (SPST) for limit
switching or for simple control tasks.
•4-20 mA / 0-20 mA galvanic isolated scalable analogue
output. The output can be active (A) or passive (P).
•RS232 galvanic isolated communication output with
MODBUS RTU slave protocol. Only one instrument can be
connected to the PLC or to the computer.
•RS485 galvanic isolated communication output with
MODBUS RTU slave protocol. 32 instrument can be
connected to the PLC or to the computer.
Note: either analogue or communication option can be
implemented at the same time.

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Operating principle
The input voltage is lead to the signal conditioner and
TRMS / DC converter stage. The DC voltage output of this
stage is converted by a 21 bit A/D converter into digital
value. The digital value is processed by a microcontroller.
The microcontroller drives the 5 digit LED display,
processes the front panel membrane keypad, drives the
limit relays, the analogue output and the communication
output.
Power supply The instrument has two power supply version:
DT4240 xx xx xx: 24 VDC, 3.5 W
DT4240 xx xx xx PS: 230 V AC/DC, 3VA / 3.5 W
3.4. Adjustment
The DT4240 xx xx xx xxcan be adjusted through the 3
button front panel keypad. All configuration parameters are
stored in the instrument EEPROM for unlimited period of
time, even when the supply voltage beeng switched off.
The instrument doesn’t need any internal adjustment.

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3.5. Display, indicators
The following figure shows the front panel of the instrument:
1. 5 digit LED display displaying the measured value and
the mnemonic messages.
2. „Rel1” yellow indicator for indicating that limit output 1 is
in “on-state” (LIMIT1).
3. „Rel2” yellow indicator for indicating that limit output 2 is
in “on-state” (LIMIT2).
4. „Status” yellow indicator for indicating that a succesfull
data exchange has granted through the communication
output.
3.6. Storage and transport
This instrument should be stored and transport in places
whose climatic conditions are in accordance with Chapter
10.1. Technical specifications, as described under the
title: Environmental conditions.
The packaging of DT4240 xx xx xx xx consist of enviroment-
friendly, recyclable cardboard is used to protect the
instrument against the impacts of normal stresses occurring
during transportation. The corrugated cardboard box is
made from environment-friendly, recyclable paper. The
inner protective material is nylon, which should be disposed
of via specialised recycling companies.

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4. Mounting
4.1. General instructions
Use the enclosed seal between the instrument and the
panel when mounting the instrument to assure IP 65 from
the front.
Mounting positions
Select a mounting position you can easily read the display
reach for mounting and connecting the instrument and that
minimises the hazard of water, dust or dump getting into the
instrument.
4.2. Main dimensions of the instrument

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4.3. Mounting
The instrument is housed in a DIN standard 96 x 48 mm
ABS case. It can be fix in the panel with the two enclosed
mounting clamps.
Preparatory steps
Dimensions of panel
cutout
1. Cut-out the panel according to the figure shows above.
The cut-out needs special tools, it must be carried out by
trained specialist personnel.

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Mounting with the
mounting clamps
2. Put on the enclosed seal onto the instrument case from
the rear side and fit it to the instrument holding frame
(Figure step 2).
3. Put the instrument into the prepared cut-out until it
possible and check the fitting of the seal between case and
mounting surface.
4. Put one of the enclosed mounting clamp onto the tip of a
screwdriver (A) and put the clamp with the help of the
screwdriwer into the hole on the side of the instrument.
5. Push the mounting clamp with your finger tip as far as
you can while keeping the case in it’s position.
Please do not exercise forces higher than necessary, as it
may cause damages to the clamp.
Repeat the 4., 5. steps with the other clamp.

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5. Connecting
5.1. Preparing the connection
Always observe the following safety instructions:
• Connect or disconnect only in the complete absence of
line voltage
• You should take note the data concerning on the
overcurrent protection in installation.
• Use only a screwdriver with appropriate head
Select connection
cable
Preparing cables
Take note the suitability of the connecting cable
(wire cross-section, insulation, etc.).
You may use either solid conductor or flexible conductor.
In case of using flexible conductor use crimped wire end.
In case of mains connection the wire cross-section should
be 1.0 mm2(min.).
In case of connection communication cables take note the
concerning prescriptions (www.modbus.org).
It’s an important rule that the power cables and signal
cables should lead on a separate way.
Prepare the cable for the connection.
Strip approx. 8 mm insulation.
In case of using flexible cable, crimp the cable end.

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5.2. Connecting the mains
The following figure shows the wiring plan, connecting the
DT4240 xx xx xx PS type instrument to the mains:
Wiring plan, connecting
the instrument to the
mains
(see also “Application
example”)
In case of DC supply the
polarity is indifferent
The following figure shows the wiring plan, connecting the
DT4240 xx xx xx type instrument to the power supply:
Wiring plan, connecting
the instrument to the
mains
(see also “Application
example”)
In case of DC supply the
polarity is indifferent
1. Loosen terminal screws.
2. Insert the wire ends into the open terminals according to
the wiring plan.
3. Screw the terminal in.
4. Check the hold of the wires in terminals by pulling on
them firmly.

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5.3. Connecting the input
The following figure shows the wiring plan, connecting the
input to the input voltage signal:
Wiring plan, connecting
the input
(see also “Application
example”)
1. Loosen terminal screws.
2. Insert the wire ends into the open terminals according to
the wiring plan.
3. Screw the terminal in.
4. Check the hold of the wires in terminals by pulling on
them firmly.

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5.4. Connecting the limit relay outputs (option).
The following figure shows the wiring plan, connecting the
limit relay outputs:
Wiring plan, connecting
the limit relay outputs
(see also “Application
example”)
1. Loosen terminal screws.
2. Insert the wire ends into the open terminals according to
the wiring plan.
3. Screw the terminal in.
4. Check the hold of the wires in terminals by pulling on
them firmly.

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5.5. Connecting the analogue output (option).
The following figure shows the wiring plan, connecting
analogue output in case of active (DT4240 xx xx IA xx) or in
case of passive (DT4240 xx xx IP xx) output:
Wiring plan, connecting
the analogue output
(see also “Application
example”)
Be careful the polarity of
the cables.
1. Loosen terminal screws.
2. Insert the wire ends into the open terminals according to
the wiring plan.
3. Screw the terminal in.
4. Check the hold of the wires in terminals by pulling on
them firmly.

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5.6. Connecting the RS232 Modbus communication
output (option).
The following figure shows the wiring plan, connecting the
RS232 Modbus communication output
(DT4240 xx xx RS2 xx):
Wiring plan, connecting
the RS232 output
(see also “Application
example”)
Be careful the polarity of
the cables.
The RS-232 Modbus communication output should be used
for short distance communication. The maximum distance is
< 10-15 m, it depends on the communication speed.
You can find useful information about the Modbus
communication at www.modbus.org.
1. Loosen terminal screws.
2. Insert the wire ends into the open terminals according to
the wiring plan.
3. Screw the terminal in.
4. Check the hold of the wires in terminals by pulling on
them firmly.

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5.7. Connecting the RS485 Modbus communication
output (option).
The following figure shows the wiring plan, connecting the
RS485 Modbus communication output
(DT4240 xx xx RS4 xx):
Wiring plan, connecting
the RS485 output
(see also “Application
example”)
Be careful the polarity of
the cables.
The RS-485 Modbus communication output should be used
for long distance communication. 32 instrument can be
connected to the PLC or to the computer.
You can find useful information about the Modbus
communication at www.modbus.org.
1. Loosen terminal screws.
2. Insert the wire ends into the open terminals according to
the wiring plan.
3. Screw the terminal in.
4. Check the hold of the wires in terminals by pulling on
them firmly.

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Checking the
connections
Check if the cables are connected properly (have you
connected all the cables, have you connected to the right
place, do not the cable-ends touch each other).
Put the instrument
under supply voltage
Put the instrument under supply voltage
After you have completed the connections, put the
instrument under supply voltage. If the supply connection is
correct the display gives light.
The factory default value of the voltage transformer ratio is 1
i.e. the instrument displays the value of the input voltage
(the secondary voltage of the voltage transformer).
Setting the voltage transformer ratio you can find in
Chapter 7.