User's Manual

EX7100 Technical Manual - Appendix A
©1999 Exicom Technologies (1996) Ltd A-5 Issue 2 – February 2001
E & M Wire Interface Standards
The EX7100 4-Wire + E&M interface conforms to the following internationally recognised
standards. It should be noted that Exicom refers to each standard as Positive M-Wire and
Negative M-wire. Positive or Negative M-wire selection is made, via six shunts on the 4-
wire interface module.
Positive M-Wire
Condition M-wire E-wire
On-Hook Open Open
Off-Hook GND GND
Negative M-Wire
Condition M-wire E-wire
On-Hook GND Open
Off-Hook -48VDC GND
-48VDC
M WIRE
E WIRE
PABX
E & M INTERFACE
RS-464 TYPE V
-48VDC
-48VDC
-48VDC
M WIRE
E WIRE
PABX
E & M INTERFACE
RS-464 TYPE 1