BFGoodrich PS-823 - 5. Battery Pack Test

BFGoodrich Avionics Systems, Inc.
Component
Maintenance
Manual
P/N 101-1075-()
5.
Battery
Pack Test
Battery Pack
inspections
and testing
should
be performed
at
100-hour/3-month
period of operation,
and after
any 15
day period of non-operation.
WARNING:
THEELECTROLYTE
USEDIN
NICKEL-CADMIUM
BATTERIES
ISTHECAUSTICSOLUTION
POTASSIUM
HYDROXIDE.
IFSPILLEDON
CLOTHINGOROTHER
MATERIALS,
BATHETHEAREA
IMMEDIATELYWITH
LARGE
QUANTITIESOF
WATER.IFTHE
ELECTROLYTEGETSON
THESKIN,
BATHE
THEENTIREAREAWITHLARGE
QUANTITIESOFWATER
ANDNEUTRAI.IZEWITH
A
BORIC
ACID
SOLUTIONORVINEGAR.IF
ELECTROLYTE
GETS
INTOTHE
EYES,
FLUSHWITH
WATER
AND
GET
MEDICAL
ATTENTION
IMMEDIATELY.
NOTE: Read
all the
Battery
Test procedures
prior to proceeding with test
and inspections.
Testing
is
performed by
monitoring
the process
of
the complete
discharge
of
a
fullycharged
Battery
Pack.
The
discharge
process
exercises
the
Battery
Pack(cells) (which
discourages
battery
"memory"),
discloses
unbalanced
cells,
and
will
indicate
the
level-of-charge that
isbeing maintained
by
the
aircraft's electrical
system.
A.
Initial
Battery
Test
Procedure
Remove
unit
from aircraft
and place at test
station.
Remove
the
Cover
Assembly (IPL
1-5,
Illustrated Parts Listing section) from
PS-823
and
inspect the
Battery
Pack
and
Battery
Access
Cover (Figure
601-2
Repair section)
for
indications of venting or corrosion.
CAUTION:
BEFORE
REMOVINGTHE
PS-823
COVER
ASSEMBLY,
THE10AMPFUSE(F2)MUST
BE
REMOVED
FROMTHEFUSE
HOLDER
TOPREVENTCIRCUITDAMAGE.
Check stored voltage
by placing
a
jumperwire across
Jl
connector
pins 11
and 13. Measure
voltage
between
pin 11
(positive)
and
pin 7 (ground).If voltage is 19.0 Vde or
higher,
add
a 7
Ohm ±1%
150-Watt
load resistor across
pins 11
(positive)
7
(ground).
This
will provide forthe
discharge of the
unit. Monitor
and chart the voltage drop/time
progression.
Compare the
discharge
curve to
the
sample
provided at
Figure 108.
If voltage
is
less
than 19.0Vde,
proceed
to
Battery
Pack
Charging
Procedure,
Paragraph
5-B.
The
healthy Battery
Pack
discharges in a manner that
charts
without sudden
or
premature
drops, and
according
to the
discharge
periods listed
with Figure 108.
If the unit tests
are
acceptable, recharge the unit
(Figure 110),
replace
the
Battery
Access Cover and
Cover
Assembly, and
return
unit to
the aircraft or appropriate
storage
container.
If the
Battery
Pack
experiences sudden
and/or premature
voltage
drops
as
indicated
by
comparison to
the
sample chart (Figure
108) proceed to
Battery
Pack and Cell Test
Procedure,
Paragraph C.
msmlitp202TestFaultlsodiskl59
24-20-03
Page 108
Revision
A
June
30, 1999