AT&T 518-600-016 manual Control unit components

Basic carrier	Expansion
	carrier

FIGURE 1-4 Control unit components.

●Power Supply Module. The Power Supply Module receives an input of 117 VAC and supplies the system with the following dc voltages: +5, -5, and -48 VDC.

The Power Supply Module can support up to 45 unit loads per carrier. (A unit load is a measure of power used to determine the electrical load of the MERLIN II system.) if the system’s power requirements exceed 45 unit loads, an Auxiliary Power Unit must be used. This device supplies an additional 20 unit loads to the system. For more information on unit loads and the Auxiliary Power Unit refer to “Determining Unit Load Requirements” on page 2-57.

If the system uses Basic Telephone (012) Modules, a

Frequency (Ring) Generator must be installed in the

Power Supply Module.

System Hardware 1-19