All wiring must be #12 AWG or larger ? Blueprint

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Stevenfyeager

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electrical contractor
Architect had on blueprint for office building that " all wire not smaller than #12 AWG " He says on the phone " whatever NEC requires. " I told him we often use #14 for lighting.
Is there a number of recessed lights (LED) specified for #14 ? Thank you
 
If you use #14 AWG conductors for lighting then you'll be using a 15 amp OCPD. That would be the limiting factor as to how many lights were on a circuit. Same thing would apply for #12's and a 20 amp OCPD.
 
Stevenfyeager said:
Architect had on blueprint for office building that " all wire not smaller than #12 AWG " He says on the phone " whatever NEC requires. " I told him we often use #14 for lighting.
Is there a number of recessed lights (LED) specified for #14 ? Thank you
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I wonder why? We generally size metric at 1.0mm2.0 for control control wiring. That's about AGW17.
 
Stevenfyeager said:
Architect had on blueprint for office building that " all wire not smaller than #12 AWG " He says on the phone " whatever NEC requires. " I told him we often use #14 for lighting.
Is there a number of recessed lights (LED) specified for #14 ? Thank you
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I think there's a perception that number 12 wire is more immune to problems with being pulled through conduit or EMT then number 14. I suspect it's probably true. Number 14 wire is not very sturdy by comparison to number 12.

I don't think it matters much for short pulls.
 
Stevenfyeager said:
Architect had on blueprint for office building that " all wire not smaller than #12 AWG " He says on the phone " whatever NEC requires. " I told him we often use #14 for lighting.
Is there a number of recessed lights (LED) specified for #14 ? Thank you
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If the drawings/specs call for #12 AWG and you believe #14 AWG is compliant and want to move forward with that, GET THE CHANGE IN WRITING! I can't overemphasize the importance of this. The specs and drawings are part of the contract, and any changes absolutely must go through whatever change process the contract calls for.
 
petersonra said:
I think there's a perception that number 12 wire is more immune to problems with being pulled through conduit or EMT then number 14. I suspect it's probably true. Number 14 wire is not very sturdy by comparison to number 12.

I don't think it matters much for short pulls.
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I have never seen that as an issue and I have pulled a lot of conduits full of 14 AWG for long distances for control circuits. Also was a common practice to pull 14 AWG control wiring in the same conduit with motor power circuits using up to 8 AWG for long distances without any issues. Often these runs would exceed 300' and some much longer.
 
There may be local amendments that require a minimum of 12 AWG.
For example, from the Warrenville, IL "Amendments to the Electrical Code":

Article 310.5 Minimum Conductor Size. All commercial and industrial work shall use minimum #12 AWG conductors.

Exception: control wiring.
 
steve66 said:
That's a common spec over here for branch circuit wiring, but smaller wire is usually allowed for control circuits.
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Yes, that's what we use control wiring for 1.0 mm which is why I asked why the architect wanted "not smaller than #12 AWG". Surely not everything needs to be #12 AWG ?
 
Specifying a minimum wire size of #12 AWG is extremely common in industrial and commercial designs. We also generally required all stranded wire. The NEC is not always a design guide. The main reason for #12 over #14, is physical strength and eliminating voltage drop issues.
 
David Castor said:
Specifying a minimum wire size of #12 AWG is extremely common in industrial and commercial designs. We also generally required all stranded wire. The NEC is not always a design guide. The main reason for #12 over #14, is physical strength and eliminating voltage drop issues.
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And the stranded spec is geographical, here in the south many specs call for solid up to #8
 
Jraef said:
We can use smaller wires within listed equipment and control systems, but not for general field wiring (without special circumstances).
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So why doesn't architect use smaller wires? That's what he asserts.
 
David Castor said:
roger said:
And the stranded spec is geographical, here in the south many specs call for solid up to #8
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Specifying a minimum wire size of #12 AWG is extremely common in industrial and commercial designs. We also generally required all stranded wire.
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I could be wrong but I thought it a standard practice to use stranded wire for industrial because of vibration.

In this new woke world we would probably use stranded and let it identify as solid. After all solid wire is just a social construct.
 
growler said:
I could be wrong but I thought it a standard practice to use stranded wire for industrial because of vibration.
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I don't think you're wrong but in my experience industrial and commercial are not treated the same. Typically when working in paper mills, plastic processing, citrus product plants, etc.... in house engineers did the design and a set of "construction specs" were not part of it.
 
This business of specs requiring #12 minimum for many commercial/industrial projects is so ingrained in most places that many believe it is a NEC requirement. There are plenty of situations in commercial/industrial where #14 is perfectly appropriate. Yes, I know many jurisdictions have a local amendment for #12. The same goes for 20 amp receptacles. In some areas it is a local custom to use 20 amp receps. And, oh, we can't forget the many specs that require 3/4 minimum raceways which in most cases is just a terrible waste of resources.
 
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