UNEC Art. 240-250
When taps are not over 10 ft in length for field installations, and they leave the enclosure or vault in which the tap is made, the ampacity of the tap conductors cannot be less than _____ the rating of the device protecting the feeder.
1/10
A surge protective device shall not be installed in circuits over _____.
1000V
If the circuit's overcurrent device exceeds _____, the conductor ampacity shall have a rating not less than the rating of the overcurrent device.
800A
The metal water piping system(s) installed in or attached to a building or structure [250.104(A)(3)] shall be bonded to _____.
Any of these ( the building or structure disconnecting means enclosure where located at the building or structure, the equipment grounding conductor run with the supply conductors, one or more grounding electrodes used)
A Type 2 surge protective device is permitted to be connected on either the line or load side of the service equipment.
False
If exposed structural metal that is interconnected to form the building frame exists in the area served by the separately derived system, it shall be bonded to the grounded conductor of each separately derived system and each bonding jumper shall be sized in accordance with Table 250.102(C)(1) based on the largest grounded conductor of the service.
False
Where the box is mounted on the surface, direct metal-to-metal contact between the device yoke and the box shall be permitted to ground the receptacle to the box if at least _____ of the insulating washers of the receptacle is (are) removed.
One
Circuit breakers used to switch 120V and 277V fluorescent lighting circuits shall be listed and marked _____.
SWD or HID
Equipment grounding conductors for feeder taps are not required to be larger than the tap conductors.
True
Outside secondary conductors can be of unlimited length without overcurrent protection at the point they receive their supply if the conductors _____.
all of these (are protected from physical damage, terminate at a single overcurrent device equal to or less than their ampacity, the overcurrent device is part of the building disconnect)
Plug fuses of the Edison-base type shall be used only _____.
as a replacement in existing installations
The connection of an unspliced _____ complying with 250.28(A) through (D) shall be made at any single point on the separately derived system from the source to the first system disconnecting means or overcurrent device, or it shall be made at the source of a separately derived system that has no disconnecting means or overcurrent devices, in accordance with 250.20(A)(1)(a) or (A)(1)(b).
system bonding jumper
Supplementary overcurrent devices used in luminaires or appliances are not required to be readily accessible.
True
Type 1 SPDs shall be permitted to be connected as specified in 242.14.
True
_____ alternating-current systems operating at 480V shall have ground detectors installed on the system.
Ungrounded
The arc energy reduction protection system shall be performance tested when first installed by _____ in accordance with the manufacturer.
a qualified person(s)
The standard ampere ratings for fuses include(s) _____.
all of these ( 1A, 6A, 601A)
When bonding enclosures, metal raceways, frames, and fittings, any nonconductive paint, enamel, or similar coating shall be removed at _____.
all of these ( contact surfaces, threads, contact points)
For a feeder-supplied building or structure, Type 2 SPDs shall be connected at the building or structure anywhere on the load side of the _____.
first overcurrent device
Type 2 surge protective device(s) shall be connected on the load side of the _____ in a separately derived system.
first overcurrent device
When a single equipment grounding conductor is used for multiple circuits in the same raceway, cable, or cable tray, the single equipment grounding conductor shall be sized according to the _____.
largest overcurrent device protecting the circuit conductors
Supplementary overcurrent protection _____.
may be used to protect internal circuits of equipment
Where the supply conductors are larger than 1,100 kcmil copper or 1,750 kcmil aluminum, the main bonding jumper shall have an area that is _____ the area of the largest phase conductor when of the same material.
not less than 12 1/2 percent of
Tap connections to a common grounding electrode conductor for multiple separately derived systems may be made to a copper or aluminum busbar that is _____ and of sufficient length to accommodate the number of terminations necessary for the installation.
not smaller than 1/4 in. thick x 2 in. wide
Outside feeder tap conductors can be of unlimited length without overcurrent protection at the point they receive their supply if the tap conductors _____.
all of these( are protected from physical damage, terminate at a single circuit breaker or a single set of fuses that limits the load to the ampacity of the tap conductors, the overcurrent device is part of the building feeder disconnect)
