Ac/Dc Voltmeter Tests (CRC)

TM 55-4920-430-13

4-45. Ac/Dc Voltmeter Tests (CRC). Allow the test set to warm up for 20 minutes before perform-

ing the following AC/DC VOLTMETER tests. Adjustment procedures are in para 4-36.

a. Set TESTER POWER switch S1 to ON.

b. Set the AC/DC VOLTMETER CIRCUIT SELECT switches to 40, 0, B, 0. Check that the METER

switch is at AC. Check that the METER RANGE switch is at 200V.

NOTE

The following test will be performed using a variable ac power supply,

50mv to 100 volts.

c. Connect the line side of the ac power supply and the positive test lead of the multimeter to EXT

METER HI jack J8. (See fig. 4-6.) Connect the other terminal of the ac power supply and the negative

test lead of the multimeter to EXT METER LO jack J9. Set the digital multimeter to read ac volts.

Adjust ac power supply frequency to 400 Hz. For each input signal level, the AC/DC VOLTMETER

shall read as listed below.

AC/DC

INPUT

METER

VOLTMETER READING (AC)

SIGNAL LEVEL

RANGE SWITCH

200 MV

49.1 to 50.9 mV

50.0 mV

98.6 to 101.4 mV

100.0 mV

148.1 to 151.9 mV

150.0 mV

187.7 to 192.3 mV

190.0 mV

flashing

220.0 mV

0.491 to 0.509 V

0.500 V

0.986 to 1.014 V

1.000 V

1.481 to 1.519 V

1.500 V

1.877 to 1.923 V

1.900 V

flashing

2.200 V

20 V

4.91 to 5.09 V

5.00 V

9.86 to 10.14V

10.00 V

14.81 to 15.19V

15.00 V

18.77 to 19.23 V

19.00 V

flashing

22.00 V

200 V

49.1 to 50.9 V

50.0 V

98.6 to 101.4 V

100.0 V

4-21