Periodic Service Procedures (Cont)

TM 11-6140-203-14-4&P

any cell reaches 0.5 volts or lower, place a shorting

discharged as shown in figure 5-5. (Be sure that the

device (metal spring strip) across the positive and

knife switch is in the open position.)

(b) Close and open the knife switch as

negative terminals of that cell. Continue this process

until the overall battery voltage drops below 10 volts.

necessary while adjusting the 0 to 7.5-ohm variable

Shutoff the RF80GT and disconnect the battery. Then

resistor for a resistance value high enough to permit the

connect individual shorting strips across the remaining

discharge current to flow at approximately the 3-hour

battery cells. Allow cells to remain shorted out for at

rate of the battery. Monitor the terminal voltage of each

least 3 hours; however, best results will be obtained

cell during discharge using the multimeter. When the

with an overnight stand.

terminal voltage of a cell reaches 0 volts, place a

(4) Deep discharge using load resistor. If a

shorting device (spring metal strip) across the positive

discharge rack or charger/analyzer is not available

and negative terminals of that cell DO NOT USE ANY

proceed as described in (a) and (b) below.

OTHER

METHOD TO DETERMINE WHEN A

SHORTING DEVICE SHOULD BE PLACED ACROSS

(a) the 0to 7.5-ohm, 1, 000-watt

THE CELL TERMINALS.

variable resistor (item 8, appx E), two multimeters, knife

switch (item 7), and nickel-cadmium battery to be

5-11