Hardware manual

Electra Elite Issue 8
System Hardware Manual 5 - 43
4.7 COID(4)/(8)-U( ) ETU
4.7.1 Description
The COID(4)/(8)-U( ) ETU is the Central Office interface
for Caller ID Detection. This ETU provides circuitry for
outside ring detection, hold, dialing, Caller ID detection,
and control functions.
This ETU can provide a CAMA trunk for Enhanced 911.
The COID(4)/(8)-U( ) ETU provides four/eight trunks that
are Loop Start with DTMF signaling only. Tip and Ring
electrical fuses are provided to comply with UL 1459
requirements.
Figure 5-24 COID(8)-U( ) ETU