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For EC&M Magazine
By Mike Holt, NEC® Consultant
Here's the follow-up to yesterday's newsletter.
This includes the answers to the questions sent, so you can see how you did.
Figure 01
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Figure 01
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For EC&M Magazine
By Mike Holt, NEC® Consultant
Here's the follow-up to yesterday's newsletter.
This includes the answers to the questions sent, so you can see how you did.
Note: The answers to these questions are based on the 2020 NEC.
Q1. What are the Code requirements for a disconnecting means for signs or outline lighting systems?
A1. Disconnecting Means
The circuit conductors to a sign, outline lighting system, or skeleton tubing must be controlled by an externally-operable switch or circuit breaker that will open all phase conductors [600.6].‚
Note: The location of the disconnect is intended to allow service or maintenance personnel and first responders, complete and local control of the disconnect.
(A) Disconnect Location. The sign disconnect is permitted to be located as follows:
(1) At the Point of Entrance to a Sign. The sign disconnect must be located where the conductors enter a sign enclosure, sign body, or pole.‚
Ex 1: A sign disconnect is not required to be located at the point the conductors enter a sign enclosure or sign body for conductors that pass through a sign where not accessible and enclosed in a Chapter 3 raceway or metal-jacketed cable.
Ex 2: A sign disconnect is not required to be located at the point the conductors enter a sign enclosure or sign body for a feeder that supplies a panelboard located within the sign under the following conditions: The feeder conductors must be enclosed where not accessible in a Chapter 3 raceway or metal-jacketed cable, a permanent field-applied warning label having sufficient durability to withstand the environment involved, complying with 110.21(B), and visible during servicing is applied to the raceway or metal cable at or near the point of the feeder circuit conductor's entry into the sign enclosure or sign body and the warning label reads:
DANGER. THIS RACEWAY CONTAINS ENERGIZED CONDUCTORS
The warning label must identify the location of the sign disconnect and the it must be capable of being locked in the open position with provisions for locking to remain in place whether the lock is installed or not [110.25].
Author's Comment:
â–ºThis rule now requires that any pass through conductors not controlled by the sign disconnect, be enclosed in an approved wiring method that does not include accessible points such as conduit bodies or junction boxes. Conductors ran in conduit bodies and junction boxes are considered to be accessible.
(2) Within Sight of the Sign. The sign disconnect must be within sight of the sign or outline lighting system it controls.‚
If the sign disconnect is not within sight of the sign or outline lighting, the disconnect must be capable of being locked in the open position with provisions for locking to remain in place whether the lock is installed or not [110.25]. A permanent field-applied warning label, having sufficient durability to withstand the environment involved and complying with 110.21(B) that identifies the location of the sign disconnect, must be located on the sign where it will be visible during servicing.‚
Author's Comment:
â–ºAccording to Article 100, Within Sight means that it is visible and not more than 50 ft from the location of the equipment.
(3) Controller Disconnect as Sign Disconnect. Signs or outline lighting systems operated by controllers located external to the sign or outline lighting system must have a disconnect for the sign controller in accordance with the following:
(1) The controller disconnect must be located within sight of or within the controller enclosure.
(2) The controller disconnect must disconnect the sign or outline lighting and the controller from all phase conductors.‚
(3) The controller disconnect must be capable of being locked in the open position with provisions for locking to remain in place whether the lock is installed or not [110.25].
Ex: Where the controller disconnect is not within sight of the controller, a permanent field-applied warning label, having sufficient durability to withstand the environment involved and in accordance with 110.21(B) that identifies the location of the sign disconnect, must be located on the sign where it can be visible during servicing.
(4) Remote Location. The disconnecting means, if located remote from the sign, sign body, or pole, must be mounted at an accessible location available to first responders and service personnel. The location of the disconnect must be marked with a label at the sign location and marked as the disconnect for the sign or outline lighting system. The label must be permanent, field-applied, have sufficient durability to withstand the environment involved, and be in accordance with 110.21(B).
Q2. What are the Code requirements for retrofit kits for signs or outline lighting systems?
A2. (A) General. A general-use or sign-specific retrofit kit for a sign or outline lighting system must include installation instructions and requirements for field conversion of a host sign. The retrofit kit must be listed and labeled [600.35].
(B) Installation. The retrofit kit must be installed in accordance with the installation instructions.
(1) Wiring Methods. Wiring methods must be in accordance with Chapter 3.
Ex: If powered from a Class 2 source, wiring methods must be in accordance with 600.12(C)(1)(2) and (C) (2) , 600.24, and 600.33.
(2) Damaged Parts. All parts that are not replaced by a retrofit kit must be inspected for damage. Any part found to be damaged or damaged during conversion of the sign must be replaced or repaired to maintain the sign or outline lighting system's dry, damp, or wet location rating.
(3) Workmanship. Field conversion workmanship must be in accordance with 110.12.
(4) Marking. The retrofitted sign must be marked in accordance with 600.4(B).
Q3. What are the NEC requirements for GFCI receptacles serving elevators and escalators?
A3. GFCI-Protected Receptacles. Receptacles rated 15A and 20A, 125V located in pits, hoistways, on the cars of elevators, and in escalator and moving walk wellways must be of the GFCI type [620.6].‚Figure 01
Receptacles rated 15A and 20A, 125V installed in machine rooms, control spaces, machinery spaces, and control rooms must be GFCI protected.‚
A permanently installed sump pump must be permanently wired or be supplied by a single receptacle that is GFCI protected.
Q4. What does the Code allow on the branch circuit for elevator cars?
A4. Branch Circuits for Elevator Car(s) [620.22]
(A) Car Light, Receptacles, Auxiliary Lighting and Ventilation. A separate branch circuit must supply the car lights. The car lights branch circuit is permitted to supply receptacles, accessory equipment (alarm devices, alarm bells, monitoring devices not part of the control system), auxiliary lighting power source, and ventilation on each elevator car or inside the operation controller.
Where there is no machine room, control room, machinery space, or control space outside the hoistway, the overcurrent device must be located outside the hoistway and accessible to qualified persons only.
Q5. What is the Code requirement for the disconnecting means serving elevators, escalators, and moving walks?
A5. A disconnect must be provided for each elevator, escalator, or moving walk. The disconnect for the main power supply conductors is not permitted to disconnect power to the branch circuits required in 620.22, 620.23, and 620.24 [620.51].
(A) Type. The disconnect must be an enclosed externally operable fused motor-circuit switch or circuit breaker that is lockable only in the open position with provisions for locking to remain in place whether the lock is installed or not [110.25].‚
Note: See ASME A17.1/CSA B44, Safety Code for Elevators and Escalators, for additional information for the disconnect.
Author's Comment:
â–ºCommonly used lockable disconnect devices can be locked in either position. This will require that the installer pay close attention to the type of disconnect that is installed.
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