Schneider Electric 66123 - Manual (Page 66)

Network Management Card & Modbus/Jbus 34022321XT indice :AE Page 66/98
Network Management Teleservice Card
APC by Schneider Electric
www.apc.com
10.1.2 RS485 link configuration and connection
10.1.2.1 RS485 connection
Normally, the master of the network sets the polarity of the line. The INMC card is a slave equipment and don’t have polarisation resistor.
The two ends of the line must be terminated. Allow for 1 or 2 terminators to avoid mismatching the line when any equipment at the end of the line
is disconnected.
The next figure gives the detail of the RS485 connector and the internals drivers:
Pin number Function
1 R- : Receiver - (input)
2 R+ : Receiver + (input)
3 T- : Transmitter - (output)
4 T+ : Transmitter + (output)
5 0 V
Important notes:
Use twisted pair cable (cable specification 0.3mm 2 and capacitance 42pF/m)
The transmission range will increase if a cable with lower capacitance and larger diameter is used.
Use shielded cable in heavy industrial environments.