Nortel ICS Install Manual page 626

626 / Problems for network or remote users
3. If you do not hear ringback, check that the target line is
assigned to a telephone and that there is a prime telephone
assigned for the DID trunk.
4. If you now hear ringback, but you also hear the noise of
your unanswered call ringing, check the
cross-connections. If all the cross-connections are correct
replace the Trunk Cartridge.
Possible problem
If remote callers are having difficulty getting through from the
private network, there may be a problem with your E&M/
DISA Trunk Cartridge.
Solution
1. Check the cross-connections for the E&M/DISA Trunk
Cartridge.
2. If the E&M trunks are connected to another Norstar
system, make sure that connections have been made as
indicated in Installation on page 227.
3. Use the following table to check for correct voltage on the
E&M/DISA leads:
Voltages on E&M leads
Leads
V
T-R
V
T1-R1
V
E-SG
V
M-SB
Modular ICS 7.1 Installer Guide
Voltage: active
125 mV AC on steady dial tone
125 mV AC on steady dial tone
0 V DC to -5 V DC
0 V DC to + 2 V DC
Voltage: inactive
0 V AC
0 V AC
-48 V DC
-48 V DC
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