ECN Forum Forums Code Related Discussion Canadian Electrical Code Topics Conductors inside switchgear

Not sure what it is you are refering to Doug.

I was not in any chat this Friday???

All 28 conductors aren't in contact for the whole 1.5 meters, but the last 6 are in a bundle for almost that distance. The architects squeeze the electrical equipment into ever shrinking spaces and the engineers specify the smallest equipment, so the manufacturer with the smallest wiring space supplies the equipment. The wiring space along side of the breakers, in a 2000 amp gear, can be as small as 6 inches by 12 inches. Add in enough space to bend a 300 MCM, and the wires are bundled together, tight. Forget spacing.

I have yet to see an engineer increase the wire size to accomodate the switch gear, nor an inspector challenge an engineer on this.

After the engineered installation, to change the application of the rules so the last breaker space is unusable (without increasing the size of every existing conductor), would be viewed dimly by most everyone. We can follow any rules than can be dreamed up; but, we must have adequate notice and the rules must be applied fairly - even to engineers.

Can we take a break from reading the code book like it was the bible, written by the all seeing and all knowing? I agree that it's a legal document (the code) and, in the end, must be applied strictly as read, but, I've never seen a heating problem from bundling cables in any equipment. Yes, in a conduit, but not in equipment. True on parallel runs in the wrong conduit, but not in a panel. I've done thermal imaging in a place were marrettes melt, but haven't seen a problem in a CDP.

We load circuits to 80% unless the load is cycling or the breaker has a 100% rating. I think the issue is already dealt with. e.g. 8-104.

I see twh has some interesting perspective on the internal wiring of a panel and you might see that I Kinda agree in that I don't think the code book extends to the inside wiring of the panelboard as that is a part 2 requirement. Interesting statement in that we should not take the code book as the bible. Frankly and i apologise in advance to those of you that will be offended by this statement but I prefer to say you should not read the Bible like it is a code book. The Code weather it is building, elevator, or electrical is the lowest standard that any regulated product is to be installed and there lies the challenge in interpretations. In the case of this discussion I don't think that the internal cable routing is governed by section 4, 8, 12 or 26.

Hi Guys...

I have not had, nor will have, the time to reply to this thread for a few days. I do have some points I wish to discuss with the group and will get back to you later on this week.

[This message has been edited by Rick Kelly (edited 06-20-2006).]

Good Day Cinner!

I sent you an E-Mail at you're listed address with a EL drawing attached (MY APPOLOGIES FOR THE CRUDE PENCIL TYPE DRAFT AS I COULD BUT WHAT THE HEY IT WAS ONLY 3:00AM), but I was wondering as to what kind of set up was being implemented here. Was it a 25KV wye Vault type to 600V with remote EL rooms outfitted with 25, 50 ect KVA with 600V in and 208 & 120V out fed to the EL rooms, or was it a panel board used with the XFMR's on the poles and the 208 120 3 Phase brought through to the pull box, to the Main SW, to the Meter Stack tap box, and out to the meter centers as required then sub fed from there?
Then I would like to ask one of my friends who is the head examiner for the ones challenging the TQ at the moment and ask for his input as to you’re question!
I hope that this will help in any way for a more direct answer to you're question!

Have a good day, and to all on the EL Forum!

Robert Wagner.