Nortel DMS-100 Series Reference Manual page 57

digital circuits which allow the unit to provide the following:
— unique tones
— test trunk center (TTC) chimes
You can combine the NT0X66CA with any of the (older) alarm system units
listed in the previous paragraph with the same office configuration.
However, the NT0X66CA input signals must be driven from separate SD
points. If the NT0X66CAinput signals are combined on the same SD points,
the large inductive voltages of the older mechanical units will damage the
NT0X66CA panel.
For a detailed description of the NT0X66CA panel, see Hardware
Description Manual.
Alarm cross-connect (AXU) panel The NT3X89EA AXU panel
contains six additional circuit paths. The additional circuit paths provide the
following:
data loop path that remains active if the OAU fails.
duplicated power source for peripheral alarms panels
frame ground signal for peripheral alarms panels
CAUTION
Service interruption
If you use the NT3X89EA in configurations with Version
2 or Version 2 EAS equipmment, disconnect the J1
shorting strap. Failure to disconnect the J1 strap could
result in service interruption or damage to equipment.
The NT3X89EA contains a J1 shorting strap. You must remove this
shorting strap if you use the NT3X89EA in configurations with Version 2 or
Version 2 EAS equipment.
For a detailed description of the NT3X89EA panel, see Hardware
Description Manual.
DMS-100 Family Alarm System Description Reference Manual BASE12
Low Power Alarm system 5-9