Specifications

48
Schneider Electric
20 mA CL – RS232 – RS422 –
RS485 links (continued)
Standards EIA 485A (March 98 update)
and TSB89 (application guidelines for TIA/
EIA-485-A)
Connection and identification:
Key:
b G = Generator
b A & B = Generator connection points
b C = Common point for the generator
b R = Receiver
b A’ & B’ = Receiver connection points
b C’ = Common point for the receiver
b T = Transmitter
b A/A’ & B/B’ = Transmitter connection points
b C/C’ = Common point for the transmitter
b RL = Load resistance.
Electrical states:
Line "A" on the transmitter is negative with respect to line "B" for a binary "1" (OFF).
Line "A" on the transmitter is positive with respect to line "B" for a binary "0" (ON).
E52332E52333
A
Lr
G
C
B
B'
A'
A/A'
R
C'
B/B'
R
T
G
C/C'
A
C
B
Guide to Integration
Modbus / Jbus