Using a DVOM(Digital Volt Ohm Meter)

Some times called a

DMM - Digital Multimeter

Or Multimeter

DVOM

• Get to know your Multimeter.

• What setting??

• Where do the leads go?? On the meter and the circuit you are checking?

DVOMLead Hook up

• This is how the leads go for Volts, Ohms & diode check.

DVOM VOLTAGE TESTS

– Test for available voltage– Polarity– Hook across (parallel) device or circuit being tested– Test for Voltage drop(loss of voltage in a circuit)– Adjust to most accurate range

DVOM VOLTAGE TESTS

Test for available voltage

DVOM VOLTAGE TESTS

Measure Voltage drop

DVOM AC Volts

• Alternating current 110 Positive to 110 Negative

• Used to measure household voltage.

• 110, 220 and up

• Some automotive applications

DVOM DC Volts

• Direct Current

• Used to measure most Automotive circuits.

• 12-24 Volts

Voltage – (V)

• Pressure• Push• Potential Energy• Electromotive Force (EMF)

• On many ohm law charts Volts is represented by the letter (E)

Ohms (R)• Used to measure the

resistance in the circuit.• Must disconnect the item

from the Battery• Use the Battery from the

meter.• Look for the M or k in

the display.• (Ω)

Ohms

Disconnect the battery It uses the battery in the meter

Diode CheckContinuity Beeper

• Use to check Diodes

• Or measure the continuity of the circuit.

• Listen to the meter.• Definition of CONTINUITY

• 1a : uninterrupted connection, succession, or union

~ merriam-webster ~

DVOM AmpsLead Hook up

• You have to move the red led to 10A

• Make sure you switch it back when done.

DVOM AC Amps

• Measure the Current flow through the circuit.

• Use to measure house hold amps.

• Look at the leads we have changed them.

DVOM DC Amps

• Measure the Current flow through the circuit.

• Notice the straight line over the A.

• This is DC Amps what we use on the car.

DVOM AMPERAGE TESTS

– Fuse Protection– Hook in SERIES with circuit– Function selector adjust to most accurate range– Maximum amperage of meter– NOTE: DOUBLE CHECK YOUR

CONNECTIONS BEFORE YOU DO TEST. CHECK YOUR SETUP!!

DVOM AMPERAGE TESTS

Hooked in SERIES with meter

In line fuse

• I use a in line fuse to prevent the DVOM from being destroyed if you hook it up wrong.

Auto Ranging

Meter tries to find the best range. Starts in the lowest range and adjusts up to find the best reading.

Auto Ranging

Manual RangingYou choose the scale you are on, start at the high end and go down until You get a overload reading and then go up one.

Depending were you have the meter it will round it offFor example reading the voltage on a battery. 1000V = 13V200V = 12.6V20V = 12.65V2V = OLSee the difference on the Ranges

This can make your readings somewhat This can make your readings somewhat inaccurateinaccurate if on the wrong range. if on the wrong range.

Manual Ranging• Different Meter’s will have different

range’s get to know your Multimeter.

• For example on a Fluke 87 you will see the following

• 0.000 4 Volts

• 00.00 40 Volts

• 000.0 400 Volts

• 0000 4000 Volts

• Learn where the decimal point goes some meters do not have volt scale on the screen

Manual Ranging 4 volts

Manual Ranging 40 volts

Manual Ranging 400 volts

Manual Ranging 4000 volts

Over Load indication

• Out of range indication if the resistance is higher than the scale you are on.

OLOUCHBlinking 3 or 1

The End