AT&T MERLIN LEGEND Installation & Maintenance Manual page 120

Installation
4.
Grasp the metal rings on the outside of the feature module
and pull up.
5. Check the HDR4 header on the processor module circuit
board for proper mode operation (see "Modify the Processor
Module for Key-Only Operation" earlier in this chapter).
Align the connectors on the new feature module with the
6.
connectors in the processor module.
Firmly press the new feature module into the processor
7.
module.
8. Insert the processor module back into the carrier (see "Insert
the Processor Module" earlier in this chapter).
Install the Auxiliary Power Unit
If the system must support more than 54 unit loads, install an
auxiliary power unit, the Auxiliary Power Unit 9024 (see "Unit
Loads" in Chapter 2).
Note: An already installed 335A auxiliary power unit can
continue to be used if no new telephones or modules are added
to the system.
Follow these steps to install an auxiliary power unit (see
Figure 21):
1. Make sure that the ON/OFF switch on the power supply
module is set to the OFF position.
2. Mount the auxiliary power unit on a surface within 2 feet of the
CU (probably the backboard on which the CU is mounted).
3. Insert one end of the modular line cord that comes with the
auxiliary power unit into the jack labeled AUX POWER INPUT
on the power supply module. Insert the other end of the
modular line cord into the jack labeled AUX POWER on the
auxiliary power unit.
3-12 The Control Unit