LADWP ELECTRICAL REPAIRER TEST
EQUIPMENT EXAM WITH QUESTIONS AND
VERIFIED ANSWERS, PLUS DETAILED
RATIONALES/EXPERT VERIFIED FOR
GUARANTEED PASS 2026/LATEST
UPDATE/INSTANT DOWNLOAD PDF
1.
A technician is troubleshooting a motor-control circuit and needs to
determine whether 120 VAC is reaching the coil of a contactor. The
circuit is energized, and the technician wants to measure the potential
difference directly across the coil terminals. Which instrument and
connection method are most appropriate?
A. Ammeter connected in parallel with the coil
B. Ohmmeter connected in series with the coil
C. Voltmeter connected in parallel across the coil terminals
D. Megohmmeter connected from one coil terminal to ground
Answer: C. Voltmeter connected in parallel across the coil terminals
Rationale: A voltage measurement determines the potential difference
between two points, so the voltmeter must be connected in parallel with
the component being evaluated. Connecting an ammeter directly
across the coil could create a very low-resistance path and potentially
damage the meter, circuit, or both. An ohmmeter or megohmmeter
should not be used on an energized circuit.
2.
A digital multimeter is set to measure current. The technician
accidentally places the meter leads directly across a 240-V source
1
,instead of placing the meter in series with the load. What is the most
serious likely consequence?
A. The meter may effectively short-circuit the source and blow its
internal fuse or sustain severe damage
B. The meter will simply display zero because current cannot be
measured in parallel
C. The meter will automatically convert itself to voltage mode
D. The circuit voltage will decrease to the meter's current range setting
Answer: A. The meter may effectively short-circuit the source and
blow its internal fuse or sustain severe damage
Rationale: An ammeter has very low internal impedance because it is
designed to be inserted in series with a circuit. Placing it directly
across a voltage source can produce extremely high current through
the meter. Proper meter lead placement, function selection, and circuit
configuration are therefore essential before making current
measurements.
3.
An Electrical Repairer measures a control transformer secondary with a
properly rated digital multimeter. The transformer is expected to provide
approximately 120 VAC, but the meter displays 0.8 VAC. Before
assuming the transformer has failed, which troubleshooting action is
most appropriate?
A. Immediately replace the transformer
B. Verify the meter's AC-voltage function, lead connections, and test-
point locations
C. Switch the meter to resistance and measure the energized transformer
D. Increase the meter's resistance range until the voltage increases
2
,Answer: B. Verify the meter's AC-voltage function, lead
connections, and test-point locations
Rationale: An unexpectedly low reading can result from incorrect
meter settings, poor probe contact, incorrect test points, or an
instrumentation problem rather than equipment failure. A disciplined
technician first verifies the measurement setup before condemning the
component. Resistance measurements must never be made on an
energized circuit.
4.
A technician needs to determine whether a 24-VDC control supply is
actually producing the correct polarity. Which measurement provides the
most direct information?
A. Resistance from positive to negative with the supply energized
B. Capacitance measurement across the supply
C. Frequency measurement between positive and negative
D. DC-voltage measurement between the positive and negative terminals
Answer: D. DC-voltage measurement between the positive and
negative terminals
Rationale: A DC-voltage measurement directly establishes both the
magnitude and, depending on probe polarity, the polarity of the
potential difference. A positive display generally indicates the red
probe is at a higher potential than the black probe; reversing the leads
typically produces a negative reading.
5.
A 10-kΩ resistor is removed from a circuit and measured with an
ohmmeter. The meter initially displays a value close to 10 kΩ, but when
3
, the technician touches the metal probe tips with bare fingers, the
displayed resistance falls significantly. What is the most likely
explanation?
A. The resistor has become shorted
B. The meter has automatically changed ranges
C. The technician's body provides a parallel resistance path across the
measurement
D. The resistor is generating additional electrical resistance
Answer: C. The technician's body provides a parallel resistance
path across the measurement
Rationale: Human skin has finite electrical resistance. Touching both
probe tips can place the body in parallel with the component,
particularly affecting higher-resistance measurements. This can
produce a lower indicated resistance. For accurate resistance
measurements, avoid contacting conductive probe tips and isolate the
component when necessary.
6.
Before using an ohmmeter to check a fuse, why should the fuse normally
be removed from the energized circuit or otherwise isolated from
external voltage?
A. External voltage can produce an incorrect resistance reading and may
damage the meter
B. The fuse will always read open when installed in a circuit
C. Resistance can only be measured on AC circuits
D. The ohmmeter requires the fuse to be magnetized first
Answer: A. External voltage can produce an incorrect resistance
reading and may damage the meter
4
EQUIPMENT EXAM WITH QUESTIONS AND
VERIFIED ANSWERS, PLUS DETAILED
RATIONALES/EXPERT VERIFIED FOR
GUARANTEED PASS 2026/LATEST
UPDATE/INSTANT DOWNLOAD PDF
1.
A technician is troubleshooting a motor-control circuit and needs to
determine whether 120 VAC is reaching the coil of a contactor. The
circuit is energized, and the technician wants to measure the potential
difference directly across the coil terminals. Which instrument and
connection method are most appropriate?
A. Ammeter connected in parallel with the coil
B. Ohmmeter connected in series with the coil
C. Voltmeter connected in parallel across the coil terminals
D. Megohmmeter connected from one coil terminal to ground
Answer: C. Voltmeter connected in parallel across the coil terminals
Rationale: A voltage measurement determines the potential difference
between two points, so the voltmeter must be connected in parallel with
the component being evaluated. Connecting an ammeter directly
across the coil could create a very low-resistance path and potentially
damage the meter, circuit, or both. An ohmmeter or megohmmeter
should not be used on an energized circuit.
2.
A digital multimeter is set to measure current. The technician
accidentally places the meter leads directly across a 240-V source
1
,instead of placing the meter in series with the load. What is the most
serious likely consequence?
A. The meter may effectively short-circuit the source and blow its
internal fuse or sustain severe damage
B. The meter will simply display zero because current cannot be
measured in parallel
C. The meter will automatically convert itself to voltage mode
D. The circuit voltage will decrease to the meter's current range setting
Answer: A. The meter may effectively short-circuit the source and
blow its internal fuse or sustain severe damage
Rationale: An ammeter has very low internal impedance because it is
designed to be inserted in series with a circuit. Placing it directly
across a voltage source can produce extremely high current through
the meter. Proper meter lead placement, function selection, and circuit
configuration are therefore essential before making current
measurements.
3.
An Electrical Repairer measures a control transformer secondary with a
properly rated digital multimeter. The transformer is expected to provide
approximately 120 VAC, but the meter displays 0.8 VAC. Before
assuming the transformer has failed, which troubleshooting action is
most appropriate?
A. Immediately replace the transformer
B. Verify the meter's AC-voltage function, lead connections, and test-
point locations
C. Switch the meter to resistance and measure the energized transformer
D. Increase the meter's resistance range until the voltage increases
2
,Answer: B. Verify the meter's AC-voltage function, lead
connections, and test-point locations
Rationale: An unexpectedly low reading can result from incorrect
meter settings, poor probe contact, incorrect test points, or an
instrumentation problem rather than equipment failure. A disciplined
technician first verifies the measurement setup before condemning the
component. Resistance measurements must never be made on an
energized circuit.
4.
A technician needs to determine whether a 24-VDC control supply is
actually producing the correct polarity. Which measurement provides the
most direct information?
A. Resistance from positive to negative with the supply energized
B. Capacitance measurement across the supply
C. Frequency measurement between positive and negative
D. DC-voltage measurement between the positive and negative terminals
Answer: D. DC-voltage measurement between the positive and
negative terminals
Rationale: A DC-voltage measurement directly establishes both the
magnitude and, depending on probe polarity, the polarity of the
potential difference. A positive display generally indicates the red
probe is at a higher potential than the black probe; reversing the leads
typically produces a negative reading.
5.
A 10-kΩ resistor is removed from a circuit and measured with an
ohmmeter. The meter initially displays a value close to 10 kΩ, but when
3
, the technician touches the metal probe tips with bare fingers, the
displayed resistance falls significantly. What is the most likely
explanation?
A. The resistor has become shorted
B. The meter has automatically changed ranges
C. The technician's body provides a parallel resistance path across the
measurement
D. The resistor is generating additional electrical resistance
Answer: C. The technician's body provides a parallel resistance
path across the measurement
Rationale: Human skin has finite electrical resistance. Touching both
probe tips can place the body in parallel with the component,
particularly affecting higher-resistance measurements. This can
produce a lower indicated resistance. For accurate resistance
measurements, avoid contacting conductive probe tips and isolate the
component when necessary.
6.
Before using an ohmmeter to check a fuse, why should the fuse normally
be removed from the energized circuit or otherwise isolated from
external voltage?
A. External voltage can produce an incorrect resistance reading and may
damage the meter
B. The fuse will always read open when installed in a circuit
C. Resistance can only be measured on AC circuits
D. The ohmmeter requires the fuse to be magnetized first
Answer: A. External voltage can produce an incorrect resistance
reading and may damage the meter
4
