Chapter 4 Flashcards
True or false.
Flexible cords and flexible cables shall be connected to devices and to fittings so that tension is not transmitted to joints or terminals.
True
What is the adjustment factor of a 10-20 conductors in a flexible cord and cable?
50%
Flexible cords and cables are not permitted in connection of utilization equipment to facilitate frequent interchange.
False, it is permitted.
All are uses of flexible cord and cables except for one: A. Connection of moving parts B. Wiring of cranes and hoists. C. Where installed in raceways D. Elevator cables
C. Except as otherwise permitted in this code.
A neutral conductor that carries only the unbalanced current from other conductors of the same circuit shall not be required to meet the requirements of a current-carrying conductor.
True or false.
True. Page 279
Flexible cords and flexible cables and their associated _______ shall be suitable for the conditions of use and location.
Fittings
In a 3-wire circuit consisting of two phase conductors and the neutral conductor of a 4-wire, 3 phase, wye connected system, a common conductor carries approximately the same current as the _________ currents of the other conductors and ________ considered to be a current-carrying conductor.
Line-to-neutral
Shall be
On a 4-wire, 3 phase, wye circuit where more than _____ percent of the load consists of nonlinear loads, there are _________ currents present in the neutral conductor and the neutral conductor shall be considered to be a current-carrying conductor.
50%
Harmonic
True or false.
An equipment grounding conductor shall be considered a current carrying conductor.
False, shall not.
Flexible cords and flexible cables shall be marked by means of a _______ attached to the ________ or carton.
Printed tag
Coil reel
Required markings on tags, cords, and cables shall also include the maximum operating temperature of the flexible cord or flexible cable at an intervals not exceeding _______.
610mm
What is the adjustment factor of a 4-6 conductors of a flexible cord or flexible cable?
80%
True or false.
Flexible cord and flexible cable shall not be permitted if contained within an enclosure for use in other spaces used for environmental air
False, shall be
The repair of hard-service cord and junior hard-service cord ________ and larger shall be permitted if conductors are spliced and the completed splice retains the insulation, outer sheath properties, and usage characteristics of the cord being spliced.
2mm^2 (1.6 mm dia)
True or false. Listed portable single pole devices that are intended to accomodate such tension at their terminals shall not be permitted to be used with single-conductor flexible cable.
False, shall be
True or false.
Flexible cords not bigger than 0.75mm^2 (1mm dia), and tinsel cords or cords having equivalent characteristics of smaller size approved for use with specific appliances, shall be considered as protected against overcurrent.
False, not bigger but smaller
Flexible cords and flexible cables shall be protected by ______ or ______ where passing through holes in covers, outlet boxes or similar enclosures.
Bushings or fittings
In industrial establishments where the conditions of maintenance and supervision ensure that only qualified persons service the installation, flexible cords and flexible cables shall be permitted to be installed in ______ raceways that are no longer than ______ to protect the flexible cord or flexible cable from physical damage.
Aboveground
15000mm
True or false.
Flexible cords shall be examined and tested at the factory and labeled after shipment.
False, before shipment dapat.
The individual conductors of a flexible cord or flexible cables shall have copper flexible _____ and shall not be smaller than required.
Stranding
Identification.
A braid finished to show a white or gray color and the braid on the other conductor or conductors finished to show a readily distinguishable solid color or colors.
Colored braid.
4.0.2.3 Identification of grounded-conductor.
True or false.
No tracer shall be used in the braid of any conductor of a flexible cord that contains a conductor having a braid finished to show white or gray.
True
Tracer in Braid
True or false.
Conductors having a continuous green color or a continuous green color with one or more yellow stripes shall not be used for other than equipment grounding conductors.
True
True or false. Cords or cables consisting of integral insulation and a jacket without a nonintegral grounding conductor shall not be permitted to be green.
False, shall be permitted
Identification.
For cords having no braids on the individual conductors, an insulation of a continuous green color or a continuous green color with one or more yellow stripes.
Colored insulation or covering.
4.0.2.4 Identification of equipment grounding conductor
For portable cables over 600 volts nominal, the conductor shall be _______ copper or larger and shall employ flexible stranding.
3.5mm^2 (2mm dia)
An equipment grounding conductors shall be provided in ______ with _____ or more conductors.
Cables
Three
True or false.
All shields shall not be connected to an equipment grounding conductor.
False, shall be
The minimum bending radii for portable cables during installation and handling in service shall be ________ to prevent damage to the cable.
Adequate
Connectors used to connect lengths of cables in a run shall be of a type that locks _____ together. Provisions shall be made to prevent opening or closing these connectors while ______. Suitable means shall be used to _____ tension at connectors and terminations.
Firmly
Energized
Eliminate
True or false.
Terminations on portable cables rated over 600 volts, nominal, shall not only be accessible to authorized and qualified personnel.
False, shall be accessible only
What is the minimum size of fixture wires?
Not smaller than 0.75mm^2 (1mm dia)
Thermoplastic insulation may stiffen at temperature lower than ______., thermoplastic insulation may also be deformed at normal temperatures where subjected go pressure, such as at points of support.
-10 degree celsius
Thermoplastic insulated fixture wires shall be durably marked on the surface at intervals not exceeding _____.
610mm
True or false.
Fixture wires shall not be used as branch circuit conductors.
True. Except as permitted elsewhere in this code.
True of false.
Switch loops shall require a grounded conductor.
False, shall not
What is the allowable ampacity for fixture wire sized 3.5 mm^2 (2mm dia) and 0.75mm^2?
23A and 6A
True or false.
Switch loop shall not require a grounded conductor
True
In table 4.2.1.5, what is the sizes of a conductor with an allowable ampacity of 8A and 17A?
1.25mm^2 (1.2mm) and 2.0 (1.6)
True or false.
Switches or circuit breakers shall not disconnect the grounded conductor of a circuit.
Truuuuu
A switch or circuit breaker shall be permitted to disconnect a grounded circuit conductor where all circuit conductors are disconnected _______, or where the device is arranged so that the grounded conductor cannot be disconnected until all the ungrounded conductors of the circuit have been disconnected.
Simultaneously
True or false.
The number of electronic lighting control switches on a branch circuits shall not exceed 4, and the number connected to any feeder on the load side of a system or main bonding jumper shall not exceed 25.
False, not 4 but 5
True or false.
Switches and circuit breaker shall be of the internally operable type mounted in an enclosure listed for the intended use.
False, externally
True or false.
Pendant and surface-type switches and knife switches mounted in an open-face switchboard or panelboard shall be permitted without enclosure.
True
_________ shall not be used as junction boxes, auxillary gutters, or raceways for conductors feeding through or tapping off to other switches or overcurrent devices.
Enclosure
A surface-mounted switch or circuit breaker shall be enclosed in a ________ enclosure.
Weatherproof
A __________ or circuit breaker shall be equipped with a weatherproof cover.
Flush-mounted switch
True or false.
Switches shall be installed within tubs or shower spaces.
False, shall not be installed.
Devices mounted so they are accessible only to qualified persons shall be permitted without barriers, provided they are located within an enclosure such that any energized parts within ______ of the manual adjustment or switch are covered by suitable barriers.
152mm
Single throw knife switches shall bd placed so that _____ will not tend to close them.
Gravity
