IGB Where?

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forabit

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I have a 480 sub panel that supplies a 112 kva transformer via 1 1/2" fmc then form the trans to a disco. via 2 1/2" fmc then to a machine via
2 1/2" fmc. where do I need igbs ?
 
Trevor, Thats interesting that you say that you don't need any.I was taught years ago that a SDS was essentially a new service and have always applied the provisions of 250.92(A) and (B) to the secondary raceways up to the first disconnect.In the primary raceways we always used a plastic bushing.
Rick
 
RUWired said:
Trevor, Thats interesting that you say that you don't need any.I was taught years ago that a SDS was essentially a new service and have always applied the provisions of 250.92(A) and (B) to the secondary raceways up to the first disconnect.In the primary raceways we always used a plastic bushing.
Rick
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You may think of it as a service if you choose, but bonding bushings aren't required. A bonding jumper and a GEC sized according to 250.66 are required just like in a service.
 
Not to dwell on the subject,but when an article says "shall be permitted" Does that give us the option of doing so if we want to? Or is it telling us we have to. Such as

250.142 Use of Grounded Circuit Conductor for Grounding Equipment

(A) Supply-Side Equipment A grounded circuit conductor "shall be permitted" to ground non?current-carrying metal parts of equipment, raceways, and other enclosures at any of the following locations:

(1) On the supply side or within the enclosure of the ac service-disconnecting means
(2) On the supply side or within the enclosure of the main disconnecting means for separate buildings as provided in 250.32(B)

(3) On the supply side or within the enclosure of the main disconnecting means or overcurrent devices of a "separately derived system" where permitted by 250.30(A)(1)
Rick
 
Not to dwell on the subject,but when an article says "shall be permitted" Does that give us the option of doing so if we want to? Or is it telling us we have to. Such as
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Here is the text from the NEC:

90.5 Mandatory Rules, Permissive Rules, and Explanatory Material.
(A) Mandatory Rules. Mandatory rules of this Code are those that identify actions that are specifically required or prohibited and are characterized by the use of the terms shall or shall not.
(B) Permissive Rules. Permissive rules of this Code are those that identify actions that are allowed but not required, are normally used to describe options or alternative methods, and are characterized by the use of the terms shall be permitted or shall not be required.
(C) Explanatory Material. Explanatory material, such as references to other standards, references to related sections of this Code, or information related to a Code rule, is included in this Code in the form of fine print notes (FPNs). Fine print notes are informational only and are not enforceable as requirements of this Code.
Brackets containing section references to another NFPA document are for informational purposes only and are provided as a guide to indicate the source of the extracted text. These bracketed references immediately follow the extracted text.
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Shall be permitted is a permissive rule and is not mandatory.
 
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