MEC 310 GENSET CONTROLLER
PM075 REV 2 09/08/20 Page 16 THOMSON TECHNOLOGY
Communication
Wiring instructions
Cable
Belden 3106A or equivalent. 22 AWG (0.324 mm
2
) shielded twisted pair, min. 95% shield coverage.
Cable shield
Connect the cable shield to earth at one end only.
GND terminal connection
In case of communication problems, the GND terminals of the MEC 310 unit and the external
device can be linked together using a third wire.
CANbus Termination resistor
The size of the terminating resistors should be 120Ω 1%, 0.5W resistor.
Option M, Modbus RTU
Connection with 3-wire shielded cable:
Modbus Slave
A
49
GND
50
B
51
A
49
GND
50
B
51
A
49
GND
50
B
51
Data +
A
GND
Data -
B
Modbus Slave
Modbus Slave
Modbus Master
Never connect the GND terminal to earth directly or through the shield!
If the GND terminal is connected to a PLC or other device, the GND connection
of this device must be isolated from earth!
Maximum length of the CANbus line is 400m.