Coi(4)/(8)-U( ) Etu; Description; Figure 5-13 Coi(8)-U( ) Etu - NEC ElectraElite 48 System Hardware Manual

Issue 6
5 - 20
4.2

COI(4)/(8)-U( ) ETU

4.2.1

Description

The COI(4)/(8)-U( ) ETU provides the Central Office
interface. The COI ETU contains circuitry for outside ring
detection, holding, dialing, and control functions.
This ETU can provide a CAMA trunk for Enhanced E911.
The COI(8)-U( ) ETU provides identical circuits to serve
up to eight CO trunks that can be any combination of Loop
Start or Ground Start with DTMF signaling.
COI(4)-U( ) is for Loop Start trunks with DTMF signaling
only. ETU Tip and Ring electrical fuses are provided to
comply with UL 1459 requirements. Refer to
COI(8)-U( ) ETU.

Figure 5-13 COI(8)-U( ) ETU

Installing Electronic Telephone Units
Electra Elite
The
Figure 5-13