Manufacturers specs vs. NEC

[ShauwnC]

Fighting a head cold today so not as sharp as I normally am. I'm trying to find wording in the code that states manufacturers specs trump nec. I don't have a great example but the best I can come up with now is the prepackaged generator systems that have a "whip" prewired and it exceeds the conduit fill without derating or something similar to that. I had an AHJ try to fail my job one time and all I had to say was it is approved from the factory that way. He called his boss and then passed it. Where is this stated in the codebook? what article?

 

[retire09]

2011 NEC 90.7

It is the intent of this Code that factory-installed internal
wiring or the construction of equipment need not be
inspected at the time of installation of the equipment, except
to detect alterations or damage, if the equipment has
been listed by a qualified electrical testing laboratory that is
recognized as having the facilities described in the preceding
paragraph and that requires suitability for installation in
accordance with this Code.

 

[retire09]

2012 IMC
304.2 Conflicts.
Where conflicts between this code and the conditions of listing or the manufacturer?s installation instructions occur, the provisions of this code shall apply.

 

[petersonra]

Fighting a head cold today so not as sharp as I normally am. I'm trying to find wording in the code that states manufacturers specs trump nec. I don't have a great example but the best I can come up with now is the prepackaged generator systems that have a "whip" prewired and it exceeds the conduit fill without derating or something similar to that. I had an AHJ try to fail my job one time and all I had to say was it is approved from the factory that way. He called his boss and then passed it. Where is this stated in the codebook? what article?

how did it exceed the fill?

 

[ShauwnC]

More than 3 current carrying conductors in flex metallic tubing without derating the conductors ( generac 17kw with 16 space transfer/ sub panel). threw the ahj off. I was thinking of the code article 110.3(B) installation and use. I have always learned manufacturers specs over rule the code but now I see there are some articles that may contradict my opinion.

 

[ShauwnC]

Would you say that 90.7 trumps the other article 304.2 conflicts?

 

[ShauwnC]

I see that in the 2011 NEC the 304.2 Article has been removed.

 

[retire09]

The NEC 90.7 pertains to the construction of listed equipment.
The 304.2 is from the international mechanical code and applies to the installation of listed equipment.
They are two very different things.

 

[iwire]

2012 IMC
304.2 Conflicts.
Where conflicts between this code and the conditions of listing or the manufacturer?s installation instructions occur, the provisions of this code shall apply.

What is the IMC?

 

[retire09]

IMC International Mechanical Code.
I'm sure the jurisdiction has adopted standard building, plumbing, mechanical and electrical codes.
They are all equally enforceable.

 

[Tony S]

If you were to alter something to meet whatever code, what happens to the manufactures warranty? Is it void?

I ask because this argument has been going on for years in the UK. People interpret a regulation one way, others another. Result, utter confusion.


The glaring example is a German washing machine manufactured with a moulded CEE7/7 plug which is cut off the fit a BS1363 plug. Some manufactures have tried to use this as a get out clause even though the washing machine is CE marked.

CEE7/7 matches both French and German standards.
CE marked. Certified for use in the EU and conforms to the Low Voltage Directive (LVD) 2006/95/EC

 

[retire09]

Anytime you modify a listed piece of equipment you probably have voided all warranties.
The electrical codes says you don't need to inspect the equipment for compliance with the NEC.
The mechanical code does regulate the installation that is field installed.
Listed equipment often does not comply with the NEC and is not required to but is is required to be installed in compliance with all adopted codes that may apply.

 

[petersonra]

More than 3 current carrying conductors in flex metallic tubing without derating the conductors ( generac 17kw with 16 space transfer/ sub panel). threw the ahj off. I was thinking of the code article 110.3(B) installation and use. I have always learned manufacturers specs over rule the code but now I see there are some articles that may contradict my opinion.

Manufacturers can't over rule the code.

How many conductors were in the flex?

 

[edlee]

2012 IMC
304.2 Conflicts.
Where conflicts between this code and the conditions of listing or the manufacturer?s installation instructions occur, the provisions of this code shall apply.

In my several decades of being an electrician, doing mostly custom residential and small retail/commercial, I have never heard of this Code. No electrical or building inspector has ever cited it as a reason for failing an installation I did. FWIW !

 

[packersparky]

IMC International Mechanical Code.
I'm sure the jurisdiction has adopted standard building, plumbing, mechanical and electrical codes.
They are all equally enforceable.

Check out 101.2 of the IMC. The scope of the IMC does not cover electrical installations. The state where I live modifies NEC 110.3 to say follow the manufacturers instructions unles they are in conflict with the NEC. Of course none of this applies to manufactured equipment that is listed.

 

[ShauwnC]

two systems come to mind. The generac 17kw I mentioned with 1-1/4" LT approx. 12" long ( chase nipple may be why it's allowed ) with 1 #4 neutral ( I think #4 ), 5 #14 , 5 #12 , 2 #6 ( I think ), and 2 #8. The other system is the reliance controls manual transfer panel which again has the 12" whip but 3/4". It doesn't have a neutral but has 4-20A circuits and 6-15A circuits with 2 conductors per circuit and again they are not derated so just #14 and #12 cables. Maybe it's just the chase code that allows this but the 20' whip that goes to the generator on the 17kw is what really threw the inspector for the loop. It has a 4 wire connection for the 12v sensing to the transfer switch, plus a hot neutral and ground that sends the power from the gen to the transfer switch. That is the cable assembly I've seen give the AHJ the most problems with.

 

[retire09]

It is common for listed equipment to NOT comply with electrical code. 18 ga wire in a light fixture or parallel #10s is an A/C unit come to mind. We do not inspect or apply the NEC to listed equipment but we do install listed equipment per the NEC and the IMC. Manufacturers installation instructions can be more restrictive than code but not less. A common example is requiring a dedicated circuit for an appliance that is otherwise not required by code. The mechanical code will require electrical connection per the NEC and most all other installation requirements for size, clearance, location, access, protection, etc are in the mechanical code.
If you inspect the entire installation and do not know mechanical code; you may be missing something.

 

[petersonra]

It is common for listed equipment to NOT comply with electrical code. 18 ga wire in a light fixture or parallel #10s is an A/C unit come to mind.

Just what section of the code would apply to the innards of any equipment? The requirements of the NEC cover the installation, not the design of equipment.

90.2 Scope.
(A) Covered. This Code covers the installation of electrical
conductors, equipment, and raceways; ...

 

[retire09]

This is the section that covers it.
Inspect the installation; not the listed equipment.
2011 NEC 90.7

It is the intent of this Code that factory-installed internal
wiring or the construction of equipment need not be
inspected at the time of installation of the equipment, except
to detect alterations or damage, if the equipment has
been listed by a qualified electrical testing laboratory that is
recognized as having the facilities described in the preceding
paragraph and that requires suitability for installation in
accordance with this Code.

 

[jaylectricity]

Is this regarding an A/C unit? :roll::angel: