BFGoodrich PS-823 - CHECKS; 2. Checks Prior to Repair (in aircraft); 3. Checks After Repair and During Re-assembly

BFGoodrich
Avionics Systems, Inc.
Component
Maintenance Manual
P/N
501-1075-()
CHECKS
1.
General
This section
is
provided
to encourage avionics
service personnel to inspect
for, sometimes,
obvious
and
overlooked
areas which
can cause or contribute
to unit failures.
2.
Checks
Prior to Repair (in
aircraft)
A.
For
PS-823
(
)/T Models
These units include internal battery testing circuitry
that provides
a Battery Test Button
and
Indicator
Lamp
in the aircraft cockpit.
This
circuitry
offers quick
reference to Emergency
Power Supply
Battery
Pack condition.
CAUTION:
IMPROPER
OPERATION
OFTHE
TESTCIRCUITCANDAMAGEUNITAND
MAKE
THE
TEST
INDICATOR
USELESS.
Proper
Battery
Test Procedure:
a. Insure aircraft
power
is OFF.
b. Press and hold the
Battery
Test Button for 10
seconds.
c. Indicator
Lamp
will illuminate
if
the Battery
Pack
contains an adequate charge and
will
extinguish after 2.5 to 4 seconds.
d. If
Lamp
does not illuminate or
only
for a very slight
moment,
the Battery
Pack will
require
a charge.
(See
Testing
and Fault Isolation
section,
Paragraph
5 Battery
Pack
Test)
CAUTION:
DO
NOTATTEMPT
THETEST
AGAINFOR2 TO3 MINUTES.
Repeated test requires a delay
of
2-3
minutes
to
allow
cool down of
resistor
R6 on the Battery
Test Assembly (IPL
1-85).
3. Checks After Repair and During
Re-assembly
A. Perform disassembly according to the Disassembly
section.
While
in progress
of
disassembly,
check:
1)
Transistors,
high-wattage
resistors and
surrounding
areas for overheating.
2) For burned, broken, or
shorted parts, components,
and
hardware.
3)
Connector and
terminal posts for
bent,
broken,
or damaged pins,
screws (heads and
threads), and casings
for breakage and cracking.
msmljtp202Checkdiskl59
24-20-03
Page501
Revision
A
June 30,
1999