Westermo MD-54 - Manual (Page 5)

16 6605-2001
Power connection
MD-54 DC
2-position screw-terminal
Connection Power
supply
– – Voltage
+ + Voltage
Screw Power
supply
L 230V
N AC power
Earth
Power connection
MD-54 AC
3-position screw-terminal
Line connection
Transmission range (RS-422/485)
Use twisted pair cable. Max transmission range 1200 metre.
(cable specifications 0.3 mm
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.
1) If shielded cable is used, connect the shield only at one end to avoid ground currents.
Twisted pairs
A’
B’
A
B
Transmitter
Receiver
MD-54
Receiver
Transmitter
Shield 1)
1
2
3
4
5
3
4
5
A/A’
B/B’
Transmitter/
Receiver
A/A’
B/B’
MD-54
Transmitter/
Receiver
RS-485 RS-422
Twisted pairs
RS-422
equipment
A
B
A’
B’
RS-485
equipment
Shield 1)