TM 11-6140-203-14-4&P
monitoring charge until charging current is 5 amperes or
4-10. Electrical Leakage Test
less per battery.
Prior to performing this check of the battery, all electrical
(1) At temperatures below 800 F (270 C)
cables should be disconnected from unit under test.
set charging voltage to 28.7 +0.2 volts dc.
CAUTION
(2) At temperatures above 80 F (27 C) set
Before making any measurements in the
charging voltage to 27.5 +0.2 volts dc.
following steps, the multimeter should
(3) See TM 9-2350-300-20-1 for charging in
always be placed at the highest dc amps
the M163A1. See TM 9-1005-286-20-1 for charging in
position.
the M167A1 towed Vulcan. Operation of APU is given
a Connect positive lead of multimeter to positive
in operator's manual TM 9-2350-300-10.
(+) terminal of battery connector.
NOTE
b. Connect negative lead to unpainted area of
Operation of heaters will lengthen
battery case such as latches or screws on the MS 3509
charging time.
connector.
c. After charging the batteries, allow the battery
c. If no indication is apparent on multimeter, set
to stand (rest) for approximately 30 minutes. Remove
function selector to DC Amps 1. If there is still no
the filler cap from each cell and adjust the
indication go down in scale until an indication is obtained.
level of electrolyte (para 4-16).
Proper reading is an indication of 3 ma or less.
d Replace the filler caps.
NOTE
e. Perform electrical leakage check (para 4-10).
If reading is greater than 3 ma, battery
4-12. Adjustment of Low Rate Battery Tap for BB-
should be thoroughly flushed, and dried
369A/U
and test performed again. If reading is
The low rate battery tap is positioned within the battery
still above 3 ma after flushing, battery
depending on the expected temperature of operation.
should be turned over to support
For operation in cold weather (32 F (0 C) or below) the
maintenance.
d. Connect negative lead of multimeter to
low rate tap is located on the positive terminal of the 8th
cell (see fig. 4-1(2)) to provide one more cell in series
negative (-) terminal of battery.
e. Connect positive lead of multimeter to
that at normal temperatures. This gives a slightly higher
operating voltage at the tap to overcome losses at low
unpainted area of battery case such as the latches or
temperature. For normal and warm temperatures, the
screws on the MS 3509 connector.
tap should be returned to the positive terminal of the 7th
f. Indications should be the same as those
cell (see fig. 4-1(1)). To accomplish this adjustment
obtained in c above. If both indications are below 3 ma
proceed as follows: a Remove covers from battery
return battery to normal service.
cases.
4-11. Charging
NOTE
Perform the following for 14ickel-Cadmium Battery BB-
All batteries within a vehicle should have
693A/U connected to the using equipment for charging.
the same tap position.
For charging a battery removed from the equipment see
b. Using insulated tools and exercising caution
paragraph 5-49.
to prevent short circuiting, remove studs as follows:
a Perform normal cleaning (para 4-13a) before
(1) Remove stud from the new position that
charging battery.
the tap will be connected to.
WARNING
(2) Remove stud holding down tap.
Explosive gases may be released during
(3) Move tap lug to new positions as
charging. Check to be sure that the
determined
charging area is well ventilated. Do not
by expected temperature of operation and replace stud
use matches, open flame, or cigarettes
and washer. Connections should be lightly buffed if
in the charging area. Guard against
corrosion is evident.
short circuits; resulting area may cause
(4) Replace stud and washer to previous
an explosion. Do not disconnect the
position. Reinstalled studs must be tightened to 50 inch-
cable from the battery until the battery
pounds (4 ft-lbs) torque.
charger has been turned off. Explosion
c. Replace covers, mark battery case by tag or
or serious burns may result.
equal method to indicate if tap is connected for cold or
normal and warm temperature operation.
b. Charge the batteries by using the 1.5 kw APU
4-3
