Alpha Technologies XM2, XM2-HV, XM2-HP - Manual (Page 44)

3.1 Power Distribution Board Setup (PDB), continued
3.1.1 Replacing the Metal Oxide Varistors (MOVs)
The PDB employs three MOVs that are mounted in sockets for easy replacement.
MOVs must be replaced by those with comparable energy and voltage ratings.
Replacement MOV P/N 160-017-19, Metal Oxide Varistor, 320Vac 420Vdc.
Tools Required:
• #2 Phillips screwdriver
• Needlenose pliers (optional)
Fig. 3-2, MOV Replacement
1. Terminate all power to unit. Turn off battery breaker and unplug battery connector.
Unplug line cord and remove all front panel connectors.
2.
Remove the five screws securing the transformer module front panel. Set the panel
and screws aside in a safe location.
3. Remove the damaged MOVs using needlenose pliers. See Fig. 3-2.
4.
Insert the new MOVs firmly into the sockets. The new MOVs must have
comparable energy and voltage ratings as those you are replacing.
5. Replace front cover.
Before proceeding, remove all power from the power supply by unplugging the
power supply from the AC power source, removing all front panel connections (i.e.,
N+1) and disconnecting the battery connector. Failure to do so could expose the
technician to potentially lethal voltages.
WARNING!
Replacement procedure:
44 017-805-B0-010 Rev. K2