Table 10: A-B Signalling States (Tie/E&M) - Mitel SX-200 EL Technician's Handbook

Technician's Handbook
Table 10: A-B Signalling States (Tie/E&M)
PBX Port CSU
Type Type
Tie Trunk DPO Tx loop open
(loop start)
DPO Rx x
DID or Tie DPT Tx
Trunk
(loop start)
DPT Rx x
TIE Trunk E&M Tx M-lead
4wire/2
wire E&M
E&M Rx x
84
PBX port Transmit Receive CSU condition to
condition to
A
channel
0
loop closure 1
x
x x
normal battery 0
reverse battery 1
x
x x
0
grounded or
open
M-lead battery 1
x
x x
analog facility
B A B
0 x x x
1 x x x
x 0 x normal battery
x 1 x reverse battery
0 x x x
1 x x x
x 0 x loop open
x 1 x loop closure
0 x x x
1 x x x
x 0 x E-lead open
x 1 x E-lead grounded
or open