Electrical Safety
How hot can an arc flash be
35000 degrees
The receptacle outlet for servicing air conditioning equipment is required to be located on the same level as the HVAC equipment and within ____ feet of the equipment.
25
In the metric system, what is the prefix for 1000?
kilo
Type MC cable is a factory assembly of one or more insulated circuit conductors with or without optical fiber members enclosed in an armor of ____ metal tape, or a smooth or corrugated metallic sheath.
interlocking
OSHA has recognized a number of organizations that meet the legal requirements in OSHA 29 CFR 1910.7. What is the industry acronym for these organizations?
A. NRTL C. QETL
B. USMCA D. NAFTA
A. NRTL
When sizing conductors and overcurrent protection, you must take 100% of the non-continuous loads plus ____ of the continuous loads.
125%
What is the metric designator for a raceway of trade size 3?
78
When a box contains fittings, such as luminaire studs, clamps, or hickeys, the number of conductors permitted in the box is one less for ____ fitting.
each type of
In the areas where ____ is enforced, the NEC® is the law.
OSHA
For motors, the OCPDs are ____.
inverse-time circuit breakers
The total voltage drop in the combined feeder and branch circuits should not exceed ____ percent.
5%
Due to repeated failures, a rule has been added in NEC _____ that, where HVAC equipment is installed on a roof, an equipment grounding conductor of the wire type must be installed in outdoor portions of metal raceway systems that use compression-type fittings.
NEC 440.9
Pressures developed during an arc blast can be as high as ______ pounds per square foot.
2160
The unit values of NEC ____________ are based on minimum load conditions and ___ power factor and might not provide sufficient capacity for the installation contemplated.
Table 220.42(A); 80%
The purpose of the National Electrical Code (NEC)® is the practical safeguarding of ____ from hazards arising from the use of electricity.
persons and property
Drain holes not larger than ____ in diameter are permitted to be drilled at appropriate locations in conduit bodies, such as LBs, or in wet-location enclosures. Properly installed drain holes or fittings will help prevent water from entering enclosures that contain energized parts that can be damaged by exposure to water.
¼ of an inch
The amount of heat in an arc flash will instantly vaporize copper and expand it ______ times its original volume.
64000
Multioutlet branch-circuit ratings are limited to 15-, 20-, 30-, 40-, and 50-ampere except on ____ premises, where they may have a higher rating
industrial
For equipment rated at 100 amperes or less, the allowable ampacity values found in the ____ column of NEC® Table 310.16 are generally to be used.
60 degrees C
In commercial buildings, ____ protection is required for all 125-volt through 250-volt receptacles supplied by single-phase branch circuits rated 150 volts or less to ground, 50 amperes or less, and all receptacles supplied by three-phase branch circuits rated 150 volts or less to ground, 100 amperes or less, installed in bathrooms, in kitchens, on rooftops, outdoors, within 6 ft (1.8 m) from the outside edge of any sink, in indoor wet locations, in locker rooms with adjacent shower facilities, and garages, bays, and similar areas.
GFCI