Nortel Meridian 1 Hardware Replacement Manual page 170

Page 170 of 250
553-3001-520 Standard 17.00 January 2002
Replacing equipment
Removing equipment
1 Turn off power to the module power supply:
— If there is a Module Power Distribution Unit (MPDU), set the circuit
breaker(s) on the associated MPDU to OFF (down).
Note: If there are two circuit breakers on the MPDU, the top one is
associated with the module power supply, the bottom one with the
ringing generator (see Figure 14 on page 171).
— If there is no MPDU, set the switch on the power supply faceplate
to OFF (down).
2 Unhook the locking devices on the power supply. Wait at least 5
minutes, then pull the power supply out of the card cage.
DANGER OF ELECTRIC SHOCK
Power must discharge. Wait five full minutes before
you remove the power supply from the module.
Installing equipment
1 Insert the replacement power supply into the vacated slot and hook the
locking devices.
Note 1: If there is a switch on the power supply, set the switch to OFF
(down) before you insert the power supply.
Note 2: On a replacement NT8D21, set option strapping the same as
on the one you removed. If there is a vintage change, be sure to check
Circuit Card: Installation and Testing (553-3001-211) for any
differences.
2 Turn on power to the module power supply. The green LED on the
power supply should light and stay lit:
— If there is an MPDU, set the circuit breaker(s) to ON (up).
— If there is no MPDU, set the power supply switch to ON (up).
3 Tag defective equipment with a description of the problem and
package it for return to a repair center.