Elenco 23 Range 20k/V VOM in Kit Form - Manual (Page 15)

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AC Voltage Test
In reading AC voltage, it is necessary to obtain a known source of AC. A 12 volt transformer is preferred. If one
is not available, use the 120VAC line.
CAUTION: Be very careful when working with 120VAC. Be sure that the range switch is in the 250 or 1000VAC
position before connecting the test leads to 120VAC.
1) Plug the red test lead into the + socket, and the black lead into the –COM socket.
2) Set the range switch to the appropriate ACV position. Touch the test leads to the power source and observe
the meter reading. Then, multiply by the appropriate scale factor.
DC Current Test
The DC current circuit is protected by a 0.5 amp fuse. Be sure that the test current is below this level.
Obtain a 68k
Ω resistor and a 1.5 volt battery (you may again use one of the 1.5V meter batteries).
Proceed as follows:
1) Plug the red test lead into the + socket and the black lead into the –COM socket.
2) Set the range switch to the 50
μ ADC position.
3) Connect the 68k
Ω resistor to the positive side of the battery. Connect the red test lead to the other side of
the resistor. Connect the black test lead to the negative side of the battery. The meter should read about
22 on the 0-50 scale. This converts directly to 22
μA.
4) Set the range switch to the 2.5mADC position. Repeat step 3 using a 1k
Ω resistor. The meter should read
about 150 on the 0-250 scale. Move the decimal point two places to the left to obtain 1.5mADC.
5) Check the remaining scales using a power supply and suitable resistors.
6) See Calibration Section for 10 amp range.
h
FE
Test
The h
FE
of a transistor is read using the six small input sockets. To measure the h
FE
(beta) of an NPN transistor,
proceed as follows.
1) If you removed the 1.5 volt battery from the multimeter, replace it now.
2) Set the range switch to the ohms X10 position.
3) Adjust the 0
ΩADJ pot for a zero reading on the ohms scale.
4) Insert the transistor into the NPN section.
5) Read the h
FE
of the transistor on the blue h
FE
scale immediately below the BATT (1.5V) scale.
8) To measure a PNP transistor, insert the transistor into the PNP section.
Transistor Leakage Test (Iceo)
1) Plug the red test lead into the P (+) and the black test lead in into N (–COM) sockets.
2) Set the range switch to the ohm X10 (15mA) position for small size transistors, for X1 (150mA) position for
large size transistors.
3) Adjust the 0
Ω ADJ for a zero reading on the ohms scale.
4) Connect the transistor as follows:
NPN Connect the test lead from the P terminal to the EMITTER (E) of the transistor.
Connect the test lead from the N terminal to the COLLECTOR (C) of the transistor.
PNP Connect the test lead from the P terminal to the COLLECTOR (C) of the transistor.
Connect the test lead from the N terminal to the EMITTER (E) of the transistor.
5) Read the leakage current on the Iceo scale. If you are on the 150mA scale, move the decimal point one
place to the right.
Battery Test
1. Set the range switch to the BATT position.
3. Plug the red test lead into the positive (+) socket and the black test lead into the –COM socket.
3. Connect 1.5V battery to the test leads and read the scale.
Good battery: The pointer stays within the GOOD (BLUE) range.
Low battery: The pointer stays within the ? range. The battery may be only good for low current equipment.
Bad battery: The pointer stays within the BAD (RED) range.