Lucent Technologies Lineage
®
2000 25A Ferroresonant Rectifier J85502A-1
Issue 4 May 1998
Spare Parts and Replacement Procedures 8 - 9
•
The ac service and dc battery buses can be safely
disconnected from the rectifier by following the first eight
steps of “Disconnecting a Rectifier,” but all work must be
done carefully because you are working with live cables at
battery bus potentials and current capabilities. The
disconnected charge battery and charge ground connectors
must be taped adequately to prevent them from contacting
each other or any other metal surface. Alternatively, the dc
battery cables from the rectifier can be disconnected at the
plant charge battery and charge ground buses.
•
Always make note of the lead connection (termination
points) before unsoldering or disconnecting them to insure
trouble-free reinstallation. This includes potentiometer
leads, or the solderless, quick-disconnect type connections
used on circuit boards, relays, inductors, transformers, and
wire bundles.
•
Always disconnect quick-disconnect connections by pulling
straight apart with pliers to avoid bending or breaking the
tabs. Do not pull on wire. Always remember to save
hardware, thermal pads, and other items necessary for
reassembly.
•
Heat-generating semiconductor components, such as diodes
and thyristors (triacs), employ heat-conductive devices for
heat sinking such as thermal grease or thermal pads. The
thermal grease used should be KS21343, L1. Diode thermal
pads used in new rectifiers are type DP126, comcode
405229147. Triac Q1 uses DP123, comcode 405229170.
•
DC capacitors can be examined to see if they have “blown”
(i.e., vented) due to voltage breakdown failure. A small hole
in the capacitor top, called a “blowhole,” is plugged in a
new or good capacitor, but is empty (blown out) in a failed
unit. Some capacitor blowholes cannot be viewed directly
until removed, or almost removed, from the rectifier. A
DANGER
The following disassembly or reinstallation procedures
MUST be performed only on a rectifier completely
disconnected from the plant battery buses, AND with no input
from the ac service panel connected to the rectifier. The plant
control cable J2A should also be disconnected from the CM2
board.
