Level 3 module 5 highlights Exam Questions
And Answers 100% Guaranteed Pass.
Types of fault current include the following - Answer✔Overloads, short circuits, ground faults,
and arc faults.
Continuous overloads can result from defective motors, overloaded equipment, or - Answer✔too
many loads on one circuit.
NEC section 110.9 states that equipment intended to interrupt current at fault levels (fuses and
circuit breakers) shall have an interrupting eating at nominal circuit voltage at least -
Answer✔Equal to the current that is available at the line terminals of the equipment.
A ground fault is an unintentional conducting connection between any of the conductors of an
electrical system and the conducting material that encloses the conductors or any conducting
material, - Answer✔Such as a metal enclosure, that is grounded or may become grounded.
For 480V circuits, however, the arc current may be as low as 38% of the available bolted fault
current and seldom exceeds - Answer✔60%.
Worn motor bearings are most likely to result in a - Answer✔Continuous overload.
The voltage rating of a fuse must be at least equal to or - Answer✔greater than the circuit
voltage.
Dual element time delay fuses are often applied in circuits subject to temporary motor overloads
and - Answer✔Surge currents to provide both high performance short circuit and overload
protection.
the primary consideration of the Underwriters Labratories, Inc. (UL) is - Answer✔Safety.
UL class R fuses are high performance 1/10A to 600A units, - Answer✔250V and 600V having
a high degree of current limitation and a root mean square symmetrical short circuit interrupting
rate of up to 200,000A.
Overload relays are designed to withstand numerous trip and reset cycles without -
Answer✔Replacement.
Normal conditions, current bypasses the spring and - Answer✔Latching mechanism.
UL tests now include the NEMA tests - Answer✔Plus other ratings.
Each group is classified by the - Answer✔Largest ampere rating of its range.
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