Line H

Question 1

which DMM function is used to measure resistance

?

Answer 1

Ohmmeter

Question 2

which DMM function is used to measure current flow in an electrical circuit ?

Answer 2

Ammeter

Question 3

What is the impedance value of most digital voltmeters?

Answer 3

10 Megaohms

Question 4

which meters are more accurate : analog or digital?

Answer 4

Digital

Question 5

which meter is more commonly used in the electrical trade: analogue or digital?

Answer 5

Digital

Question 6

What does DMM stand for?

Answer 6

Digital Multimeter

Question 7

which meter is uses to take current measurements without opening the circuit?

Answer 7

Clamp on Ammeter

Question 8

Which of the two meter types, true RMS or average responding would be used by an electrician testing an electronic ballast in florescent lighting fixtures

Answer 8

True RMS DMM

Question 9

When measuring the voltage across a component, will meter loading cause the meter reading to be higher or lower than the voltage across the component without the meter in the circuit

Answer 9

Lower

Question 10

Which DMM setting would be used to measure the voltage output of an alternator?

Answer 10

A/C

Question 11

Which DMM setting would be used to measure the voltage output of an Rectifier?

Answer 11

D/C

Question 12

The source voltage of the circuit is 120 volts AC, and the resistance of the circuit is 10 ohms. what type of ammeter would you use to measure the current in the circuit?

Answer 12

clamp on 120/10 = 12A, DMM Max 10a

Question 13

list two advantages of clamp on style of ammeter over a DMM

Answer 13

• Circuit does not have to be interrupted or deenergized to take a current measurement
• Able to measure currents in excess of 10A

Question 14

which meter would be selected to provide quick and easy testing of whether the fuse is open or has a complete path through it?

Answer 14

The continuity function of a DMM

Question 15

When using the diode test function to a silicon diode, if the diode is good , a DMM will display the _______?

Answer 15

The forward bias voltage drop

Question 16

Which measurement function of a DMM requires an internal battery to provide current flow though the circuit

Answer 16

Resistance or Ohms

Question 17

Analog meters are used over DMM style meters due to their superior accuracy

A) true
B) false

Answer 17

False

Question 18

When testing for the potential of a set of series connected batteries, which function of the DMM would be used

A) Hold button

B) DC voltmeter

C) Continuity

D) AC voltmeter

Answer 18

DC Voltmeter

Question 19

A DMM with an autoranging feature will automatically select the________ with the best accuracy and resolution for the measurement.

A) screen

B)range

C)dial setting

D)connection

Answer 19

range

Question 20

What is the impedance of most digital voltmeters?

A) 2000 ohms

B) 10 megaohms

C) 10 milliohms

D) 2000 megaohms

Answer 20

10 Megaohms

Question 21

Care should be taken that the ___________ function is never used on a live circuit

A) Ammeter

B) DC Voltmeter

C) Wattmeter

D) Ohmmeter

Answer 21

Ohmmeter

Question 22

True RMS meters use an integrated circuit to ________ the RMS value of the waveform under test.

A) rectify

B) reduce

C) extend

D) compute

Answer 22

Compute

Question 23

In order for a DMM to accurately measure the voltage of a variable speed drive a true RMS meter is required.

A)True
B)False

Answer 23

True

Question 24

Comparing a meter’s reading with a precisely accurate laboratory meter is called:

A)calibrating

B) parallaxing

C)standardizing

D)zeroing

Answer 24

Calibrating

Question 25

What answer best reflects the position that the Digital multimeter can be used in.

A) vertically

B) horizontally

C) either horizontally or vertically

D) in any position

Answer 25

In any position

Question 26

When using the ammeter function of a DMM, it is important to?

A)De-energize the circuit while taking readings.

B)Turn the function dial to the off position.

C)Confirm the meter is rated to handle the expected current.

D)add loops to the leads to increase the accuracy of your reading.

Answer 26

Confirm the meter is rated to handle the expected current

Question 27

Most DMM’s have a wattmeter function.

1) True
2) False

Answer 27

false

Question 28

What advantage(s) does a digital wattmeter have over an analog wattmeter?

1) No batteries required
2) Accuracy
3) Ease of use
4) all of the above

Answer 28

accuracy

Question 29

A digital wattmeter takes current and voltage measurements electronically, thousands of times per second.

1) True
2) False

Answer 29

True

Question 30

If you are not familiar with the use of a particular meter, you should:

1) Use heavy-duty leads.
2) Take the cover off first and inspect the mechanism.
3) Send it out for calibration.
4) Read the instruction booklet carefully.

Answer 30

Read the instruction booklet carefully

Question 31

When using a digital wattmeter, you should always:

1) read the manufacturers instructions.
2) de-energize the circuit prior to making connections.
3) connect the current jacks in series with the circuit being tested.
4) Connect the voltage jacks in parallel with the circuit being tested.
5) All of the above.

Answer 31

All of the above

Question 32

A digital wattmeter measures the_________consumed in an electrical circuit.

1) current
2) voltage
3) electrons
4) power

Answer 32

Power

Question 33

A wattmeter is to be connected to a heating circuit. The resistance of the heater is 29.71 ohms. The source voltage is known to be 208v. The wattmeter is rated for 1500 watts and the fuse in it is rated for 10 amps. Can the wattmeter safely measure the power output of the heater?

1) Yes
2) No
3) Only if the fuse is rated for the voltage.

Answer 33

Yes