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Hackenschmidt
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Discussion Starter · #23 ·
Another way to go, nipple from the 4x4 to the transformer box and use #14 wire, or use a transformer that mounts right on the box, Hammond makes control transformers that mount like doorbell transformers.

Class 2 Energy Limiting Box Mount (BF Series) - Hammond Mfg. (hammfg.com)

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We typically use one of these styles to prevent any need to have 120vac freely wired inside our cabinets. We always keep anything over 24vac rated in a separate enclosure. So anyone working inside the main cabinet does not need to worry about any voltage greater then about 24vac.
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It's inside a cabinet but it's a field install by an electrician not an engineered install that has been pre approved for anything.
LoL ... no sh1t ! :LOL:

An engineer can do a lot of things, but he can't break code.
 

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Which code can he not break?
The one I posted earlier. Our section 16 (Class 1 2 and 3 circuits) can use reduced size wiring, but the code I posted is the feed for the primary of the Transformer in a class 2 circuit. Needs to be wired according to code (nothing smaller than # 14, be protected ... etc etc )
 

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Chief Flunky
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It’s inside the cabinet so an engineer can design anything he wants to sign off on.

I’m sure the insulation on that wire isn’t rated for it’s use.
That’s simply not true to put it mildly. Engineers are not the AHJ and cannot bypass NEC where it is required. Control panels do not have to follow 409.22 (and thus 450) but they do have to follow some other Code. Inside Listed panels UL is typically the Code but it can follow other NRTL standards. These are more restrictive than NEC. The ampacity tables in UL 508A are the 60 C column.

450.3 says circuit breaker or fuse for primary only protection at 2 A or less is the next standard size up. 240.5 lists standard breaker sizes. The smallest is 15 A. Second the primary side overcurrent protection has nothing to do with transformer feeder ampacity. Ampacity is set by the full load rating of the primary side which at 100 VA is less than 1 A. Thus the NEC non-motor minimum AWG or #18 applies.

It should be obvious that the OCPD is clearly never intended to provide any overload protection whatsoever with a 300% multiplier. It’s short circuit only. This comes from the secondary side. On transformers under 2 A NEC simply omits the requirement.
 

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Discussion Starter · #31 ·
This is a very strange looking panel imo

Why do you have the 120v separated from everything else in the enclosure, inception style?

It's 2022, use fingersafe components and keep the wiring in seperate panduits
Mostly because we have un skilled site staff and sometimes even Jr techs who think all small wiring is safe so the start sticking there fingers in the cookie jar lol
 

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When I first started at this plant I saw operators who would open up 480v MCC buckets and go blindly stabbing around with a screwdriver. Luckily that has gotten better for the most part.
 

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Discussion Starter · #34 ·
The one I posted earlier. Our section 16 (Class 1 2 and 3 circuits) can use reduced size wiring, but the code I posted is the feed for the primary of the Transformer in a class 2 circuit. Needs to be wired according to code (nothing smaller than # 14, be protected ... etc etc )
Does CEC not have something similar to this ""

The input leads of a transformer or other power source supplying Class 2 circuits shall be permitted to be smaller than 14 AWG, if not over 12 inches (305 mm) long and if the conductor insulation is rated at not less than 600 volts. In no case shall such leads be smaller than 18 AWG.""
 

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Does CEC not have something similar to this ""

The input leads of a transformer or other power source supplying Class 2 circuits shall be permitted to be smaller than 14 AWG, if not over 12 inches (305 mm) long and if the conductor insulation is rated at not less than 600 volts. In no case shall such leads be smaller than 18 AWG.""
Not in the CEC.
If your company has a copy of CSA C22.2 NO. 286-17 (Industrial Control Panels), it could be in there.

When I was getting ESA field approvals, they would only accept and call out CEC rules/violations.
CSA cUL etc, use the Panel codes and standards.

 
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