MAINTENANCE OF THE M113 PER CARRIER - OD1601 LESSON 2/TASK 2
3 Setting up the AN/URM-105 for DC Voltage Reading.
The first step in
setting up the AN/URM-105 multimeter for dc voltage measurement is mechanically
zeroing the multimeter.
The selector switch must then be turned to the dc volts
range required for the voltage being measured (figure 13 on page 36). As with the
other two multimeters, if the voltage to be measured is not known, begin with the
selector switch in the dc VOLTS 1000 position. Then, if the first reading was less
than 100 volts, set the selector on dc VOLTS 100. If the second reading was less
than 10 volts, set the selector at dc VOLTS 10 and take a third reading.
(d) DC Voltage Measurement.
The method for measuring dc voltage is similar
for all three multimeters.
First, mechanically zero and set up the multimeter.
Remember, if the voltage to be measured is unknown, be sure to start with the
highest range available on the meter being used to avoid damage to the multimeter.
Connect the red probe to the positive (+) side of the circuit being tested and the
black probe to the negative (-) side. If the needle tries to move off scale to the
left, reverse the probes on the circuit under test. On the Simpson 160, read the
dc scale for the range chosen by the selector switch. For the TS-352 B/U read the
dc scale for the range of the jack to which the red lead is connected.
AN/URM-105, read the upper black straight lined portion of the ac and dc volts
scale for the range chosen by the selector switch.
(3) Electrical System - Problem: FUEL QUANTITY INDICATOR FAILS TO REGISTER WHEN
MASTER SWITCH IS ON, ALTHOUGH TANKS HOLD KNOWN QUANTITY OF FUEL.
(a) Find the name of the item that doesn't work.
For this example, the name of the item is the "Fuel Electrical System,"
and would be found on page 2-82, TM 9-2300-257-20.
(b) Find the problem with the item.
The problem to be rectified in this example is, FUEL QUANTITY INDICATOR
FAILS TO REGISTER WHEN MASTER SWITCH IS ON, ALTHOUGH TANKS HOLD KNOWN
QUANTITY OF FUEL, and would be found on page 2-82.1.