1|Page
Instrumentation NCCER Practice Test with 230
Questions and Correct Answers/ NCCER
Instrumentation Correctly Answered Practice
Exam
What should be done with tools or extension cords with
the ground prong removed or missing? - ...ANSWER...✓✓
They should be removed immediately from use and
tagged "Do not use".
Who is allowed to remove another electrician's tag or
lock from any valve, switch or piece of equipment without
proper documentation and approval? - ...ANSWER...✓✓
No one
Why can a lead acid battery be an explosive hazard? -
...ANSWER...✓✓ Hydrogen gas is produced during charge
and discharge
When is it acceptable to perform maintenance repair on a
plant system without lockout and tagout? -
...ANSWER...✓✓ Never
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What is the purpose of a lockout/tagout? - ...ANSWER...✓✓
prevents operation
What is the resistance of a 1,250-watt, 240-volt resistive
heater? - ...ANSWER...✓✓ 46.1 ohms (P/V & V/I)
What is the source voltage in a circuit that consumes
1,200 watts at a current or 5 amps? - ...ANSWER...✓✓ 240
volts (P/I)
What is voltage? - ...ANSWER...✓✓ electromotive force
All of the following are CORRECT formulas for "ohm's
law" EXCEPT - ...ANSWER...✓✓ E = RXI
When three equal resistors are connected in parallel, the
total resistance is, - ...ANSWER...✓✓ Less than any one
resistor
A voltage source of a circuit provides 240 volts and draws
48 amps. How much resistance is in the circuit? -
...ANSWER...✓✓ 5 ohms (V/I)
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The MINIMUM acceptable DC mega ohm resistance of a
4,160 volt motor is approximately? - ...ANSWER...✓✓ 4.2
megohms
What is the formula for calculating total resistance in a
series circuit with three resistors? - ...ANSWER...✓✓ RT =
R1+R2+R3
Why should the test leads of a "megger" NEVER be
touched by anyone when in use? - ...ANSWER...✓✓ It
could result in an electrical shock
An analog voltmeter is being connected to a 24 V DC
circuit. Polarity is reversed. What regarding will occur? -
...ANSWER...✓✓ 0 or fewer volts
How is a voltmeter connected in a circuit? -
...ANSWER...✓✓ parallel only
The voltage of a DC circuit is to be measured. How should
the voltmeter be connected to ensure proper polarity? -
...ANSWER...✓✓ the negative terminal of the meter is
Instrumentation NCCER Practice Test with 230
Questions and Correct Answers/ NCCER
Instrumentation Correctly Answered Practice
Exam
What should be done with tools or extension cords with
the ground prong removed or missing? - ...ANSWER...✓✓
They should be removed immediately from use and
tagged "Do not use".
Who is allowed to remove another electrician's tag or
lock from any valve, switch or piece of equipment without
proper documentation and approval? - ...ANSWER...✓✓
No one
Why can a lead acid battery be an explosive hazard? -
...ANSWER...✓✓ Hydrogen gas is produced during charge
and discharge
When is it acceptable to perform maintenance repair on a
plant system without lockout and tagout? -
...ANSWER...✓✓ Never
,2|Page
What is the purpose of a lockout/tagout? - ...ANSWER...✓✓
prevents operation
What is the resistance of a 1,250-watt, 240-volt resistive
heater? - ...ANSWER...✓✓ 46.1 ohms (P/V & V/I)
What is the source voltage in a circuit that consumes
1,200 watts at a current or 5 amps? - ...ANSWER...✓✓ 240
volts (P/I)
What is voltage? - ...ANSWER...✓✓ electromotive force
All of the following are CORRECT formulas for "ohm's
law" EXCEPT - ...ANSWER...✓✓ E = RXI
When three equal resistors are connected in parallel, the
total resistance is, - ...ANSWER...✓✓ Less than any one
resistor
A voltage source of a circuit provides 240 volts and draws
48 amps. How much resistance is in the circuit? -
...ANSWER...✓✓ 5 ohms (V/I)
, 3|Page
The MINIMUM acceptable DC mega ohm resistance of a
4,160 volt motor is approximately? - ...ANSWER...✓✓ 4.2
megohms
What is the formula for calculating total resistance in a
series circuit with three resistors? - ...ANSWER...✓✓ RT =
R1+R2+R3
Why should the test leads of a "megger" NEVER be
touched by anyone when in use? - ...ANSWER...✓✓ It
could result in an electrical shock
An analog voltmeter is being connected to a 24 V DC
circuit. Polarity is reversed. What regarding will occur? -
...ANSWER...✓✓ 0 or fewer volts
How is a voltmeter connected in a circuit? -
...ANSWER...✓✓ parallel only
The voltage of a DC circuit is to be measured. How should
the voltmeter be connected to ensure proper polarity? -
...ANSWER...✓✓ the negative terminal of the meter is
