TM5-3820-256-10
d. Battery Voltage Check.
NOTE
Make the following checks with the test set connected. Also, a voltmeter is needed to make the tests. If
batteries need to be replaced, any 9-volt transistor radio battery will work satisfactorily.
(1)
Single 9-volt battery. Set the voltmeter function switch to +DC volts and the range switch at full scale
reading closest to, but not lower than 10 volts. Connect the red (+) lead to the battery positive terminal and the black (-)
lead to the battery negative terminal. Record the voltmeter reading. Place the function switch in CUR or CAL mode,
energize the current switch, and record the battery voltage under load. The voltage should remain at or slightly below the
open circuit load. If the voltage continues to drop with the current switch energized, the battery is weak and should be
replaced.
(2)
Five 9-volt batteries. Set the voltmeter function switch at +DC and the range switch at full scale reading
closest to, but not lower than 50 volts. Connect the red (+) lead to an exposed battery positive terminal and the black (-)
lead to an exposed battery negative terminal of the battery string. Record the voltmeter reading. Place the instruments
function switch to CUR or CAL mode, energize the current switch, and record the battery voltage under load. The
voltage should remain at or slightly below the open circuit load. If the voltage continues the drop with the current switch
energized, the batteries are weak and all five should be replaced.
3-22
Troubleshooting the Pump. The following paragraphs describe some of the possible troubles that may be
encountered. Tables 3-12 and 3-1 5 describe some possible malfunctions that may occur to cause those problems, with
the checks and tests that must be made, and the action needed to correct the condition.
Table 3-12. Fuses Blow when Motor Starts
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
1.
INCORRECT SUP-
Using a voltmeter,
If voltage is not correct, contact
PLY VOLTAGE.
check the line termi-
Direct Support Maintenance.
nals. Voltage must be
within plus or minus
10% of nominal.
2.
INCORRECT FUSES.
Check fuses for recom-
Replace with proper fuses; clean
mended sizes; also,
any dirt or corrosion from conn-
check for loose, dirty,
ections.
or corroded connections
in the fuse receptacle.
3.
DEFECTIVE
Check voltage at cont-
Contact Direct Support Mainte-
PRESSURE
act points. Improper
nance.
SWITCH
contact of switch points
can cause voltage less
than line voltage.
3-57
