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mmacdonell
November 24, 2019, 01:26 PM
9. Which of the following is not a type of contactor used in circuit breakers?
Your Answer: Electro-pneumatic
Correct Answer: Vacuum

How is Vacuum not a type of contactor used in CB's?
Nick1234
November 24, 2019, 02:05 PM
9. Which of the following is not a type of contactor used in circuit breakers?
Your Answer: Electro-pneumatic
Correct Answer: Vacuum

How is Vacuum not a type of contactor used in CB's?

I agree Vacuum contactor is a thing, but maybe they are using vacuum in the sense that you cannot DLRO across a vacuum. If so the question and answers are badly worded.
mbaxter1
November 25, 2019, 04:11 PM
9. Which of the following is not a type of contactor used in circuit breakers?
Your Answer: Electro-pneumatic
Correct Answer: Vacuum

How is Vacuum not a type of contactor used in CB's?

Isn't a contactor a device that is controlled by another voltage, like what you see in a motor starter? I didn't think circuit breakers had "contactors" except maybe in the control circuit.
breny426
December 8, 2020, 10:00 AM
9. Which of the following is not a type of contactor used in circuit breakers?
Your Answer: Electro-pneumatic
Correct Answer: Vacuum

How is Vacuum not a type of contactor used in CB's?

Thinking about it now, vacuum is used to insulate when the contacts get opened. All the other options are what the circuit breaker uses to make contact.
cycle61alt
December 9, 2020, 10:52 AM
Thinking about it now, vacuum is used to insulate when the contacts get opened. All the other options are what the circuit breaker uses to make contact.

Anybody know what were the rest of the options?

Probably clarify the exact wording of the explanation, all the other options are the operating mechanism of the breaker, rather than the contact itself. Typical confusing language. Ugh.
breny426
December 9, 2020, 08:57 PM
Anybody know what were the rest of the options?

Probably clarify the exact wording of the explanation, all the other options are the operating mechanism of the breaker, rather than the contact itself. Typical confusing language. Ugh.

I apologize. I don't recall exactly what the other answers were, but I think it was something like the following:

a. Magnetic
b. Pneumatic
c. Electro-pneumatic

Anyway you slice it, though, I don't believe there are any breakers that are OPERATED by vacuum.
cycle61alt
December 9, 2020, 09:06 PM
I apologize. I don't recall exactly what the other answers were, but I think it was something like the following:

a. Magnetic
b. Pneumatic
c. Electro-pneumatic

Anyway you slice it, though, I don't believe there are any breakers that are OPERATED by vacuum.

Lol I think old Mercedes windshield wipers and door locks have the patent on that.