GE Industrial Solutions ZBTSCTH SERIES 100 - 4000 AMPS - Manual (Page 14)

ZBTSCTH Operation and Maintenance Manual (46R-7000) 12 Zenith Controls, Inc.
SECTION III - MAINTENANCE AND TESTING
A preventive maintenance program will insure
high reliability and long life for the transfer switch.
The preventive maintenance program for the
transfer switch should include the following
items:
1. INSPECTION AND CLEANING
HAZARDOUS VOLTAGE
(Can Cause Severe Injury or Death)
Turn OFF all power before installation,
adjustment, or removal of transfer switch or
DANGER !
Before doing any work on the transfer switch,
de-energize all sources of power. The switch
should be inspected for any accumulation of
dust, dirt, or moisture, and should be cleaned by
vacuuming or wiping with a dry cloth or soft
brush. DO NOT use a blower since debris may
become lodged in the electrical and mechanical
components and cause damage.
Remove the transfer switch barriers and check
the condition of the contacts. Any surface
deposits must be removed with a clean cloth (DO
NOT USE EMERY CLOTH OR A FILE). If the
contacts are pitted or worn excessively, they
should be replaced. A general inspection of
mechanical integrity should be made to include
loose, broken or badly worn parts.
2. SERVICING
All worn or inoperative parts must be replaced
using Zenith recommended replacement parts.
Appendix B at the back of this manual includes
replacement part information for typical power
and control panel configurations. When ordering
parts provide the model number or serial number
from the transfer switch rating nameplate.
The operating mechanism of the transfer switch
is lubricated with Lubriplate 105. The lubricant
applied at the factory provides adequate
lubrication for the lifetime of the switch. Should
debris contaminate the mechanism, clean and
apply additional Lubriplate.
3. TESTING
After completing the inspection, cleaning and
servicing of the transfer switch, reinstall the
switch cover, and close and lock the cabinet
door. Reclose the circuit breakers feeding the
utility and generator sources to the switch.
Initiate the electrical transfer test by activating
the TS test switch. This de-energizes the engine
start relay. The transfer switch closes into
Emergency only after the sync-check relay
ensures the proper phase relationship of both
sources. After the transfer switch closes into
Emergency, the SE limit switch becomes
activated to de-energize the CCE relay and
energize the CCNO relay. This opens the
transfer switch out of Normal. When the transfer
switch has opened out of Normal, the SNO-2
limit switch activates to de-energize the CCNO
relay. The transfer switch has now closed into
emergency power without interrupting the load.
Turning the TS to AUTO initiates re-transfer to
Normal. The transfer switch closes into Normal,
only after the sync-check relay ensures the
proper phase relationship of both sources. After
the transfer switch closes into Normal, the SN
limit switch becomes activated to de-energize the
CCN relay and energize the CCEO relay; the
transfer switch opens out of Emergency. Then
the SEO-2 limit switch activates to de-energize
the CCEO relay. The transfer switch has now
closed back into normal power without
interrupting the load.
The transfer switch defaults to an open transition
transfer when the Normal source fails. Closed
transition transfer is not possible with one source
available. Open transition transfer for testing can
be selected via the transition mode selector
switch.
A 24 VDC circuit is supplied to control the alarm
and warning indicators. To insure continuous
power to this circuit, a constant 24 VDC can be
supplied by the customer from the engine start
battery.
NOTICE !
A periodic test of the transfer switch under
load conditions is recommended to insure
proper operation.