Thus, you do not create a new branch circuit. A fitting is an accessory, such as a locknut or bushing, whose function is primarily mechanical, rather than electrical in nature. However, conductors that run above the top level of a window may be less than 914 mm (3.0 ft) from the window. Neutral Conductor or Point C. The neutral point is the midpoint on a single-phase portion of a 3 phase Delta System. For each given ppp-series, identify ppp and determine whether the series converges. Noncurrent-carrying metal parts of fixed equipment, if required to be grounded by this subpart, shall be grounded by an equipment grounding conductor that is contained within the same raceway, cable, or cord, or runs with or encloses the circuit conductors. n the Duplicate Busbar System, continuity of service is possible even if the Main, A: All the exposed noncurrent carrying metal parts of an information technology system shall be bonded, A: Correct option is B that is ELECTRIC GROUND CONDUCTORS must be capable of withstanding the higher, A: Jumpers allow the computer to shut down the electrical circuit, allowing electricity to flow to, A: Question. Transformer top surfaces that are horizontal and readily accessible must be marked to prohibit storage on those surfaces. Receptacles connected to circuits having different voltages, frequencies, or types of current (ac or dc) on the same premises shall be of such design that the attachment plugs used on these circuits are not interchangeable. B. This record shall be kept by means of logs, color coding, or other effective means and shall be maintained until replaced by a more current record. "I have learned, in whatsoever STATE I am, therewi, http://www.usahardware.com/inet/shop/item/30550/icn/20-068163/bussman/bp_sru.htm. Primary Conductor = 6 AWG conductor rated 65A at 75C [Sec. Exposed noncurrent-carrying metal parts of fixed equipment that may become energized shall be grounded under any of the following conditions: If within 2.44 m (8 ft) vertically or 1.52 m (5 ft) horizontally of ground or grounded metal objects and subject to employee contact; If located in a wet or damp location and not isolated; If supplied by a metal-clad, metal-sheathed, or grounded metal raceway wiring method; or. . Where the ground-fault circuit-interrupter protection required by paragraph (b)(3)(ii)(B) of this section is not available for receptacles other than 125-volt, single-phase, 15-, 20-, and 30-ampere, the employer shall establish and implement an assured equipment grounding conductor program covering cord sets, receptacles that are not a part of the building or structure, and equipment connected by cord and plug that are available for use or used by employees on those receptacles. A transformer must have a disconnect within sight of the transformer unless the disconnect location is field marked on the transformer, and the disconnect is capable of being locked in the open position per Sec. In this example, the receptacle is that outlet. The requirement for maintaining a vertical clearance of 914 mm (3.0 ft) from the edge of the roof does not apply to the final conductor span, where the conductors are attached to the side of a building. . This test record shall identify each receptacle, cord set, and cord- and plug-connected equipment that passed the test and shall indicate the last date it was tested or the interval for which it was tested. white, gray, green, or, green with yellow stripe(s). 2023 Endeavor Business Media, LLC. The frame of a portable generator need not be grounded and may serve as the grounding electrode for a system supplied by the generator under the following conditions: The generator supplies only equipment mounted on the generator or cord- and plug-connected equipment through receptacles mounted on the generator, or both; and. Is other equipment in there? Oddly enough, you will find the underlying concept in NFPA 70E, Standard for Electrical Safety in the Workplace. Where the neutral is not grounded on the load side of the circuit, the current transformer may link all three phase conductors and the grounded circuit conductor (neutral); and. of the box. Essentially, this Article covers transformers supplying power and lighting loads. Volume in boxes can be increased by using ____ rings, domed covers, extension rings, or similar items. Overcurrent devices shall be readily accessible and shall be installed so that the center of the grip of the operating handle of the switch or circuit breaker, when in its highest position, is not more than 2.0 m (6 ft 7 in.) A reduction in clearance above only the overhanging portion of the roof to not less than 457 mm (18 in.) A surface, flush, or freestanding raceway designed to hold conductors and receptacles (in the field or the factory). (If these areas are accessible to other than pedestrian traffic, then one of the other conditions applies). Problems due to aging during operationC. Wire connectors, pigtails, locknuts, bushings, raceway connectors, grounding screws, and equipment bonding jumpers are not factors when calculating ____. outer liquidtight, nonmetallic, sunlight-resistant jacket. Micro-grid Location Dry A. It has no direct connection from circuit conductors. 450.3(B)]. Location Wet A. LOCATED WITHIN A GROUNDED JUNCTION BOX, B. . Dry locations are those not normally subject to moisture except on a temporary basis such as a building under Construction NEC. The service point is the point of connection between the facilities of the serving utility and the premises wiring. So, if the transformer vents face a beam-mounted or wall-mounted fire extinguisher, remove the extinguisher and remount it on something that is out of the vent exhaust path. Select one: A. The full form of the acronym, MCCB, is Miniature Case Circuit Breaker. Between the three-phase line and the disconnect switch. Transformers having a secondary voltage not exceeding 1,000V, with primary overcurrent protection only, must have the primary overcurrent protective device sized per the percentages shown in Table 450.3(B) and the percentages mentioned in its applicable notes [Sec. f(x)=4x+53f(x)=\sqrt{4 x+5}-3 If the circuit\'s overcurrent device exceeds _____, the conductor ampacity shall have a rating not less than the rating of the overcurrent device. I would only agree if the fuse were within the premises wiring system. LOCATED WITHIN A GROUNDED JUNCTION BOX. Clearance from ground. A luminaire that weighs more than ____ pounds shall be supported independently of the outlet box, unless the outlet box is listed and marked for the maximum weight to be supported. 15A for 14 AWG copper, 20A for 12 AWG copper, and 30A for 10 AWG copper. 250.12]. Installations built before August 13, 2007, Installations built on or after August 13, 2007, Circuit breakers used as switches in 120-volt and 277-volt, fluorescent lighting circuits shall be listed and marked "SWD. The main bonding jumper is connection at the service between the grounded circuit conductor and the equipment grounding conductor. Formal interpretations of the NEC are govered by regional construction authorities. The neutral point is the common point on a Wye-connection in a polyphase system. Overcurrent devices do not have to be readily accessible if located within anded jacobs k. the connecting means is readily accessible the total of the conceitdees of wood local andards Located at the equipmenl where excess is achieved by the we of poetic ANS: PTS: REF: Definitions 3. connected to ground or to a conductive body that extends the ground connection. LOCATED ADJACENT TO THE EQUIPMENT WHERE ACCESS IS ACHIEVED BY THE USE OF PORTABLE MEANS. Select one: Example: A service disconnecting means must be readily accessible or near the entry point of the service conductor. Bonding Jumper (Main) When metal parts are required to be electrically connected, a reliable conductor (Bonding Jumper) is installed, thereby guaranteeing electrical conductivity. A grounding electrode is a(n) ____ object that establishes a direct connection to earth. 240.6(A)]. Neutral Conductor or Point B. Listed equipment protected by a system of double insulation, or its equivalent, and distinctively marked as such. Receptacles and cord connectors having grounding contacts shall have those contacts effectively grounded except for receptacles mounted on portable and vehicle-mounted generators in accordance with paragraph (g)(3) of this section and replacement receptacles installed in accordance with paragraph (b)(2)(iv) of this section. Branch Circuits A. Ground detectors are installed on the control system; If the system is an isolated power system that supplies circuits in health care facilities; or. For installations made before April 16, 1981, electric equipment is also considered to be effectively grounded if it is secured to, and in metallic contact with, the grounded structural metal frame of a building. Which of the following would help avoid the choke effect in grounding electrode conductors?A. Electric equipment is considered to be effectively grounded if it is secured to, and in electrical contact with, a metal rack or structure that is provided for its support and the metal rack or structure is grounded by the method specified for the noncurrent-carrying metal parts of fixed equipment in paragraph (g)(8)(i) of this section. A fixed or portable optional standby systems, A: Choose the correct option located adjacent to the equipment where access is achieved by the use of portable means. A wire, bus, screw, or similar suitable conductor is acceptable as a main bonding. You are using an out of date browser. The switch is, A: Given, FLAC NEC Whi MULTIPLE CHOICE 1 Wiring components are considered accessible if(t) access can be gained without damaging the structure or finish of the building or if (2) they are ae Sledstry of the wiring here salatile in the ANS: PTS: 1 REF: Definitions 2. T(v1,v2,v3)=(v1+v2,v2+v3,v3)T(v_1, v_2,v_3) = (v_1+v_2, v_2+v_3, v_3) Service conductors installed as open conductors or multiconductor cable without an overall outer jacket shall have a clearance of not less than 914 mm (3.0 ft) from windows that are designed to be opened, doors, porches, balconies, ladders, stairs, fire escapes, and similar locations. Where connected to a branch circuit having a rating in excess of 20 amperes, lampholders shall be of the heavy-duty type. Systems supplying portable or mobile high voltage equipment, other than substations installed on a temporary basis, shall comply with the following: The system shall have its neutral grounded through an impedance. Exposed noncurrent-carrying metal parts of cord- and plug-connected equipment that may become energized shall be grounded under any of the following conditions: If in hazardous (classified) locations (see 1910.307); If operated at over 150 volts to ground, except for guarded motors and metal frames of electrically heated appliances if the appliance frames are permanently and effectively insulated from ground; If the equipment is of the following types: Refrigerators, freezers, and air conditioners; Clothes-washing, clothes-drying, and dishwashing machines, sump pumps, and electric aquarium equipment; Hand-held motor-operated tools, stationary and fixed motor-operated tools, and light industrial motor-operated tools; Motor-operated appliances of the following types: hedge clippers, lawn mowers, snow blowers, and wet scrubbers; Cord- and plug-connected appliances used in damp or wet locations, or by employees standing on the ground or on metal floors or working inside of metal tanks or boilers; Portable and mobile X-ray and associated equipment; Tools likely to be used in wet and conductive locations; and. Nonmetallic-sheathed cable not fastened to the box must be secured within ____ in. IMO, if you stick a fuse within a cord, and plug that cord into a receptacle outlet, you are outside the premises wiring system. Branch Circuit Individual An individual branch circuit supplies only one piece of utilization equipment. The conductors and equipment that deliver energy from the serving utility to the wiring system of the premises are called the service, Service Conductors A. Grounding triad A) located within a grounded junction box B) the disconnecting means is readily accessible C) the total load of the adjacent circuit does not exceed local standards D) located adjacent to the equipment where access is achieved by the use of portable means Using bonding bushes on the ends of the raceway, Four 4 AWG copper conductors with THHN insulation installed in EMT in a basement. The area above a roof surface subject to pedestrian or vehicular traffic shall have a vertical clearance from the roof surface in accordance with the clearance requirements of paragraph (c)(2) of this section. Lighting Outlets A. Knowing the NEC rules for transformers is only a start. 450.13]. One of the most common applications for "readily accessible" occurs in 240.24(A), in which the NEC states that overcurrent devices must be readily accessible and installed so that the center of the grip of the operating handle of the switch or circuit breaker, when in its highest position, is not more than 6 feet, 7 inches above the floor . Draw clearly, neatly, and properly the Circuit Schematic Diagram for a SINGLE BUSBAR SYSTEM with BUS SECTIONALIZATION. What is the angle pull for a raceway in the horizontal dimension where the trade size of the largest raceway is 3 and the sum of the other raceways in the same row on the same wall is 4?v. In the 2014 NEC, the definition of readily accessible in Article 100 was revised to make it clear that something is not readily accessible if a tool is needed to gain access to it. This prevents the equipment from being readily accessible to people in general and is a good safety measure. above the floor or working platform, unless one of the following applies: Applying solder to the connectionD. Accessible (Equipment) Accessible equipment is equipment not guarded by locked doors, elevators, or other. All rights reserved. The record shall be made available on the jobsite for inspection by the Assistant Secretary and any affected employee. Decreased bending radius during operation, Which of the following is a term missing from the National Electrical Code but used by manufacturers of equipment that's suitable for use as service equipment? OSHA 6.Underwriter's Laboratories NFPA TS: 1 REF: The National ANS: Electrical Code 8. neutral disconnect link, 18. If a delta-connected high voltage system is used to supply the equipment, a system neutral shall be derived. Electric Metal Tubing (EMT) provides protection from ____. In Sight A. NEC defines in sight from, within, or within sight to the applied equipment and indicates that specified items or equipment is visible and not more than 50 Ft. apart. Home > 2022 > June > 10 > Uncategorized > overcurrent devices do not have to be readily accessible if. IMO, if you stick a fuse within a cord, and plug that cord into a receptacle outlet, you are outside the premises wiring system. Install the service disconnecting means at a readily accessible location. As long as you can remove the trim and access the junction box it will be considered readily accessible! An ____ is the organization, office, or individual responsible for enforcing the requirements of a code. Figure F.1 has you start by establishing the context. A violinist places her finger so that the vibrating section of a 1.0 g/m string has a length of 30 cm, then she draws her bow across it. Two exceptions to the make readily accessible rule are noted in Sec. For the purposes of Art. A circuit breaker with a slash rating, such as 120/240 V or 480Y/277 V, may only be installed in a circuit where the nominal voltage of any conductor to ground does not exceed the lower of the two values of the circuit breaker's voltage rating and the nominal voltage between any two conductors does not exceed the higher value of the circuit breaker's voltage rating. The neutral conductor of a multiphase system in which one phase is used as a neutral conductor shall be grounded. Service Equipment A. But you can reduce or eliminate power quality problems by correcting grounding and bonding errors at the transformer or somewhere else (e.g., at the utilization equipment). Arc-Fault Circuit Interrupter A device intended to provide protection from the effects of arc faults by recognizing characteristics unique to arcing and by deenergizing the circuit when an arc fault is detected. I dont like the 'new definition' of 'Branch circuit overcurrent device'. Branch Circuit Multi-wire D. Although the box contains a multi-wire branch circuit, only one ungrounded (hot) conductor is feeding this duplex receptacle. or greater. A conductor used as an equipment grounding conductor shall be identifiable and distinguishable from all other conductors. Box calculations for 4 AWG and larger conductors (under 600 volts) are performed based on the ____. NEC 2008 article 100 definitions. All noncurrent-carrying metal parts of portable equipment and fixed equipment, including their associated fences, housings, enclosures, and supporting structures, shall be grounded. Location Damp A. A conductor used as a grounded conductor shall be identifiable and distinguishable from all other conductors.