ETC403 Circuit Breaker and Fuses

_____________ is a device used for closing and interrupting a circuit between separable

contacts under both normal and abnormal conditions.

• circuit breaker

• switch

• disconnect switch

• fuse

When the handle of the Circuit Breaker is in the position "A", the circuit breaker is ____________.

• TRIP status

• OFF status

• OFF status

• RESET mode

Circuit breakers are classified as 100A, 225A, 400A, 1000A, and 2000A frames. These numbers are called __________.

• frame sizes

• voltage rating

• sizes

• none of the choices

Circuit breaker __________ indicate the maximum electrical system

voltage on which they can be applied

• voltage rating

• ampere rating

• frame size

• none of the choices

Circuit breakers can be rated for alternating current (AC) applications only

• TRUE

• FALSE

Answer explanation

its for both AC and DC

CB voltage rating must be equal or greater than the voltage of the electrical system

• TRUE

• FALSE

Circuit breakers have two types of current rating. What are these?

• continuous current rating

• fault current interrupting capacity

• voltage rating

• prospective fault current

____________is the

maximum current (in amperes) that it will carry

continuously

• continuous current rating

• interrupting fault rating

• voltage rating

• all of the choices

What information is indicated by letter "X" on the circuit breaker handle?

• ampere rating

• voltage rating

• fault current rating

• all of the choices

The ____________ of a

circuit breaker is the maximum short circuit current

at which the breaker will safely interrupt

the circuit.

• AIC

• ampere rating

• voltage rating

• all of the choices