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Modbus RTU interface
The COM16 module is equipped with a 3-wire RS485 interface. The Modbus RTU connector is a 9-pin female Sub-D connector with the
following pinout:
Cables connecting COM16 modules via RS485 must contain three insulated conductors and a shield. The three isolated conductors
connect to Pins 1, 5 & 9. The RS485 Reference must only be grounded at one end, preferably at the master. Grounding the RS485
Reference in multiple locations can allow common mode voltages to be imposed on the RS485 Transceiver terminals which can prevent
communication and potentially damage the device.
The cable shield must only be grounded at one end, preferably at the master. Grounding the shield in multiple locations can allow circulating
ground currents in the shield which can prevent successful communication.
Write Enable input
The COM16 Module is equipped with an input that must be activated to allow the module to accept remote control commands as well as
remote parameterization. When this input is not active, the module will reject all incoming packets that would normally change the state of
an output (open/close circuit breaker) or change protective parameters. Normal polling and communication of data are not affected.
The following commands are blocked if the Write Enable input is inactive:
- opening/closing circuit breaker
- resetting after a trip
- Changing any protective function parameters and extended protective function parameters
- changing any communications parameter (e.g. address)
- changing any parameter of the metering function (e.g. demand period length)
- resetting any diagnostic or service-related counter or indicator
- setting/resetting outputs of the digital output modules
The following commands are always allowed, independent of the state of the Write Enable input:
- changing and setting the trigger settings of the waveform capture function
- reading the contents of the waveform buffer
- changing alarm and setpoint function settings
- changing any of the customer-changeable text strings
- resetting the min/max log
- setting/resetting the "Free Output" of the COM16 module
- setting system time
Pin
1
RS485 Reference
5
Transceiver Terminal 1, V1 voltage
9
Transceiver Terminal 0, V0 voltage
2-4, 6-8
Not connected
Summary of Contents for UL 489
Page 36: ...5 21 Frame size II 3000 A Frame size III 1 Holes 14 mm 0720 1 0721_nu ...
Page 63: ...7 2 Horizontal connectors 0733_nu top view ...
Page 64: ...7 3 Rear vertical connectors 0734_nu top view rear view ...
Page 65: ...7 4 Front connectors 0736_nu front view top view ...
Page 66: ...7 5 Front connectors and pressure wire terminals 0737_nu top view front view ...
Page 67: ...7 6 7 2 Frame size II fixed mounted version 0494 3_nu ...
Page 68: ...7 7 Class C always 0494 5_nu top view rear view ...
Page 69: ...7 8 2500 0738_nu LH side view front view ...
Page 71: ...7 10 7 4 Frame size III fixed mounted version 0495 1_nu LH side view ...
Page 72: ...7 11 0495 2_nu top view top view ...
Page 73: ...7 12 0495 3_nu top view rear view ...
Page 75: ...7 14 7 5 Door cut outs fixed mounted circuit breaker Frame size I 0735_nu ...
Page 76: ...7 15 Frame size II III 0496_nu ...
Page 77: ...7 16 7 6 Frame size I draw out version 0745_nu ...
Page 78: ...7 17 0746_nu rear view top view ...
Page 79: ...7 18 0747_nu bottom view ...
Page 80: ...7 19 0748_nu ...
Page 81: ...7 20 0749_nu ...
Page 82: ...7 21 7 7 Frame size II draw out version 0490 1_ul ...
Page 86: ...7 25 7 8 Frame size III draw out version ...
Page 87: ...7 26 ...
Page 88: ...7 27 ...
Page 89: ...7 28 7 9 Door cut outs for draw out circuit breakers Frame size I 0750_nu ...
Page 91: ...7 30 7 11 External sensor for neutral conductor WLNCT2 ...
Page 92: ...7 31 WLNCT3 ...
Page 107: ...9 5 I tripping Ground fault tripping ...
Page 351: ......