Hardware Manual for the PCD2.M5 Series│Document 26/856; Version EN 12│2014-07-24
Saia-Burgess Controls AG
Definitions of serial interfaces
Annex
A-4
A
A.2.3 TTY/current loop
Signals to TTY/current loop
Terminal 1
TS
Transmitter Source
Sender
Terminal 3
TA
Transmitter Anode
Terminal 6
TC
Transmitter Cathode
Terminal 8
TG
Transmitter Ground
Terminal 2
RS
Receiver Source
Recipient
Terminal 4
RA
Receiver Anode
Terminal 7
RC
Receiver Cathode
Terminal 9
RG
Receiver Ground
Signal type
Set-point
Nominal value
Power for logic L (space)
-20 mA to + 2 mA
0 mA
Power for logic H (mark)
+12 mA to +24 mA
+20 mA
Neutral voltage to TS, RS
+16 V to +24 V
+24 V
Short circuit power on TS, RS
+18 mA to +29.6 mA
+23.2 mA
The idle state of the data signals = "mark"
By wiring to the cable connector, the user selects either an "active" or "passive" cir-
cuit.
The max. transmission rate for TTY/current loops at 20 mA is 9600 bps.