Digital Volt/Ohm Meter (DVOM)
Digital Volt-Ohmmeter:
PURPOSE
Like Analog meters, Digital Volt/Ohm Meters (DVOM's), can be used to measure and compare actual values with expected circuit values.
Advantages Over Analog Meters
DVOM's have a numerical readout, which is more precise than the needle reading on an analog meter. DVOM's have a higher internal impedance (10 Meg ohms typical), which prevents loading or damaging digital (computer related), circuits.
OPERATION
Voltmeter Connection:
When measuring voltage always connect the voltmeter in parallel to the circuit or component.
CAUTION: Connecting a voltmeter in series with a circuit may damage the meter and/or circuit.
Ohmmeter Connection:
Before attempting to measure the resistance of a circuit or component, always disconnect any voltage sources from the circuit or component.
Connect the ohmmeter across--in parallel with--the resistance to be measured.
CAUTION: Connecting an ohmmeter to a circuit while voltage is present may damage the meter and/or the circuit.
Ammeter Connection:
Connect the ammeter in series with the circuit.
CAUTION: Make sure polarity is correct prior to energizing circuit.