# Electrical Tester

Names of Parts
The  electrical tester can be used for measuring the current, voltage, and resistance of an electrical circuit, as well as to check the continuity of a circuit and testing diodes.

The following measurements can be performed by operating the function selector switch:
Alternating current voltage measurement
Purpose:
For measuring the voltage of household or factory power supply lines, alternating current voltage circuits, and the tap voltages of a power transformer.
Measurement method:
Set the function selector switch to the alternating current voltage measurement range and connect the test leads. The polarities of the probes are interchangeable.
Direct current voltage measurement
Purpose:
For measuring the voltage of various types of batteries, electrical devices, and transistor circuits, and the voltages and voltage drops in circuits.
Measurement method:
Set the function selector switch to the direct current voltage measurement range. Place the black, negative test lead, to the ground potential, the red, positive test lead on the area to be tested, and take a reading.
Resistance measurement
Purpose:
For measuring the resistance of a resistor, continuity of a circuit, short circuit (0 Ω), open circuit (infinity ∞ Ω).
Measurement method:
Set the function selector switch to resistance/continuity. (If the display shows “” at this time, the tester is in the continuity testing mode. Therefore, press the blue Ω/ mode selector switch to change the tester to resistance inspection mode.) Then, place a test lead on each end of a resistor or a coil to measure the resistance. Make sure that no voltage is applied to the resistor at this time. The diode cannot be measured in this range because the used voltage is low.
Continuity check
Purpose:
For checking the continuity of a circuit.
Measurement method:
Set the function selector switch to the continuity range. (Make sure that the display shows “” at this time. If it does not, press the Ω/ mode selector switch to change the tester to continuity mode.) Connect the test leads to the circuit to be tested. The buzzer will sound if the circuit has continuity.
Diode test
Purpose:
For testing a diode.
Measurement method:
Set the function selector switch to the diode test mode. Check the continuity in both directions. If the diode has continuity in one direction and there is no continuity when the test leads are interchanged, the diode is determined to be normal.
If the diode has continuity in both directions, it is shorted. If it does not have continuity in either direction, it has an open circuit.
Direct current amperage measurement
Purpose:
For measuring the amperage consumption of devices that operate with a direct current.
Measurement method:
Set the function selector switch to the amperage measurement range. Select an area for inserting the positive test lead with the proper range. To measure the amperage of a circuit, the ammeter must be connected in series to the circuit. Therefore, separate an area in the circuit in which to connect the test leads. Connect the positive test lead to the side with the higher potential and the negative test lead to the side with the lower potential, and take a reading.