CWB Level 2 Study Questions rev 1
Questions and Answers Verified
Solutions Latest Update (2026/2027)
Question:
connected to the same voltage source. Select the correct statement.
A. in each parallel path the resistance must be equalized to create equal
voltage.
B. the current flowing in each parallel path must be the same as the voltage.
C. the current flowing in each parallel path depends on the resistance in
each path
D. the current flowing in each parallel path depends on the capacitance in
each path
Answer:
C. the current flowing in each parallel path depends on the resistance in
each path
Question:
The duty cycle of a welding power supply is based upon delivering its rated
output for a given
number of minutes. Which of the following statements is correct.
A. a 300 amp/60% duty cycle machine is rated to deliver 300 amps for 6
minutes in a ten minute
period
B. a 300 amp/30% duty cycle machine is rated to deliver 300 amps in a ten
minute period
C. a 250 amp/30% duty cycle machine is rated to deliver 250 amps for 30
minutes separated by
,10 minutes at rest
D. a 300 amp/60% duty cycle machine is rated to deliver 500 amps maximum
for 6 minutes in a
ten minute period
Answer:
A. a 300 amp/60% duty cycle machine is rated to deliver
300 amps for 6 minutes in a ten minute period
Question:
Conventional transformer-rectifiers;
A. convert direct current into alternating current
B. convert alternating current into direct current
C. convert alternating current into pulsed current
D. convert direct current into pulsed current
Answer:
B. convert alternating current into
direct current
Question:
A conventional diode placed in a circuit allows the passage of current in one
direction only. A
silicon controlled rectifier(SCR) operates slightly differently. How does it
work?
A. an SCR conducts current in both directions until turned on and current
flow is then prevented
B. an SCR is non-conductive until turned onland then allows current to flow
in both directions
C. an SCR is non-conductive until turned on, allowing current to flow in one
direction only until
,the flow of current stops
Answer:
C. an SCR is non-conductive until turned on, allowing
current to flow in one direction only until the flow of current stops
Question:
What is the term for voltage measured across the output terminals of a
welding machine when
no current is being drawn?
A. diode voltage
B. operating voltage
C. open circuit voltage
D. terminal voltage
Answer:
C. open circuit voltage
Question:
A 60% duty cycle means that the power supply can deliver its rated output
for:
A 60% of the rated output only
B. 60% over the rated output followed by 4 minutes at rest
C. 6 minutes at rest followed by 4 minutes at rated output
D. 6 minutes at rated output followed by 4 minutes at rest
Answer:
D. 6 minutes at
rated output followed by 4 minutes at rest
, Question:
One of the simplest ways of controlling the output of a welding transformer
is to change the
efficiency of coupling between the primary and secondary coils. How can
this be done?
A) slide a piece of wood between the primary and the secondary coils
B) design the transformer with either a moving core or moving primary coils
C) design the transformer with a number of taps to select different output
curves
D) use the timed firing of SCR's to control total conduction time
Answer:
B. design the
transformer with either a moving core or moving primary coils
Question:
When choosing between AC and DC output;
A. the process generally determines the type of current
B. high current output machines are always both AC/DC
C. DC is generally used for very high output applications
D. most supplies are equipped with constant voltage/constant current
options
Answer:
A. the process generally determines the type of current
Question:
Which of the following metals has the lowest electrical resistivity?
A aluminum
Questions and Answers Verified
Solutions Latest Update (2026/2027)
Question:
connected to the same voltage source. Select the correct statement.
A. in each parallel path the resistance must be equalized to create equal
voltage.
B. the current flowing in each parallel path must be the same as the voltage.
C. the current flowing in each parallel path depends on the resistance in
each path
D. the current flowing in each parallel path depends on the capacitance in
each path
Answer:
C. the current flowing in each parallel path depends on the resistance in
each path
Question:
The duty cycle of a welding power supply is based upon delivering its rated
output for a given
number of minutes. Which of the following statements is correct.
A. a 300 amp/60% duty cycle machine is rated to deliver 300 amps for 6
minutes in a ten minute
period
B. a 300 amp/30% duty cycle machine is rated to deliver 300 amps in a ten
minute period
C. a 250 amp/30% duty cycle machine is rated to deliver 250 amps for 30
minutes separated by
,10 minutes at rest
D. a 300 amp/60% duty cycle machine is rated to deliver 500 amps maximum
for 6 minutes in a
ten minute period
Answer:
A. a 300 amp/60% duty cycle machine is rated to deliver
300 amps for 6 minutes in a ten minute period
Question:
Conventional transformer-rectifiers;
A. convert direct current into alternating current
B. convert alternating current into direct current
C. convert alternating current into pulsed current
D. convert direct current into pulsed current
Answer:
B. convert alternating current into
direct current
Question:
A conventional diode placed in a circuit allows the passage of current in one
direction only. A
silicon controlled rectifier(SCR) operates slightly differently. How does it
work?
A. an SCR conducts current in both directions until turned on and current
flow is then prevented
B. an SCR is non-conductive until turned onland then allows current to flow
in both directions
C. an SCR is non-conductive until turned on, allowing current to flow in one
direction only until
,the flow of current stops
Answer:
C. an SCR is non-conductive until turned on, allowing
current to flow in one direction only until the flow of current stops
Question:
What is the term for voltage measured across the output terminals of a
welding machine when
no current is being drawn?
A. diode voltage
B. operating voltage
C. open circuit voltage
D. terminal voltage
Answer:
C. open circuit voltage
Question:
A 60% duty cycle means that the power supply can deliver its rated output
for:
A 60% of the rated output only
B. 60% over the rated output followed by 4 minutes at rest
C. 6 minutes at rest followed by 4 minutes at rated output
D. 6 minutes at rated output followed by 4 minutes at rest
Answer:
D. 6 minutes at
rated output followed by 4 minutes at rest
, Question:
One of the simplest ways of controlling the output of a welding transformer
is to change the
efficiency of coupling between the primary and secondary coils. How can
this be done?
A) slide a piece of wood between the primary and the secondary coils
B) design the transformer with either a moving core or moving primary coils
C) design the transformer with a number of taps to select different output
curves
D) use the timed firing of SCR's to control total conduction time
Answer:
B. design the
transformer with either a moving core or moving primary coils
Question:
When choosing between AC and DC output;
A. the process generally determines the type of current
B. high current output machines are always both AC/DC
C. DC is generally used for very high output applications
D. most supplies are equipped with constant voltage/constant current
options
Answer:
A. the process generally determines the type of current
Question:
Which of the following metals has the lowest electrical resistivity?
A aluminum
