Lucent Technologies 555-661-140 manual Checking Unit Loads, Unit Loads for Hybrid/PBX Mode

MERLIN LEGEND Communications System Release 6.1	Issue 1
Installation 555-661-140	August 1998
Installing the Control Unit	Page 2-17
Unit Loads

Unit Loads

A unit load is a measure of power (1.9 watts) that you use to determine the electrical load that the components listed below place on the control unit’s power supply.

■Telephones and adjuncts

■800 DID modules

Only the telephones and adjuncts that connect to the analog and digital extension jacks (ports) on the control unit require unit load calculation. When calculating unit load, do not include any equipment with its own power supply.

Checking Unit Loads

In the event of maintenance or equipment changes, recalculate the unit loads for each carrier where there is a new configuration. Use the worksheet in Appendix B, “Unit Load Calculation Worksheet.”

As a general rule, if you can distribute the 800 DID modules and telephone modules equally across the carriers, you prevent unnecessary drain on any one carrier. However, the rule varies depending on the system’s operating mode. The next two sections provide the rules for calculating unit loads in various modes.

Unit Loads for Hybrid/PBX Mode

Older power supplies (models 391A1 or 391A2) generally support six modules of any type in Hybrid/PBX mode, without requiring an upgrade to a newer power supply (model 391A3 or 391C1). If the following conditions are true, however, the unit loads on a carrier can exceed the 54-unit maximum and, therefore, require a newer power supply (model

391A3 or 391C1):

■All six carrier slots are occupied by MLX telephone or analog multiline telephone modules.