ECN Forum Forums General Topics of the Trade General Discussion Area Breakers used as switches

If there is nothing wrong electrically, then it all comes down to cost. Ask yourself:

• How often are the breakers needing replacing?

• How many times will it need to be done over the next 10 years?

• What it will it cost over the next ten years?

• What will it cost to re-wire the circuits to switches or a contactor?

For your part number, just HID i.e. QO120HID. I do not think that switching (no pundt intended) to HID breakers will cure your problem. What is the deciding factor that tells you the breakers need replacing? How often are the breakers needing replacing?

Almost every breaker manufactured now is SWD rated (15 & 20A SINGLE pole.. Even the tandem breakers made by Cutler and Sq-D are SWD rated... The only breaker I found without a SWD rating on it is the narrow (1/2") Federal Pioneer style. Their regular (1") version ARE rated SWD..

I agree that using a contactor and a switch is the ultimate way to go, but I think one of the reasons they used the breakers as switches was it was simpler and cheaper to eliminate extra swiches, contactors and the like, and for some applications, it was the ideal method of lighting control.

A.D

A master switch and a contactor to turn all the lights on at once may not be the way to go......at least not in Sacramento, California (where the OP is from).

Individual switches abound because of Part 6, Title 24 (CA's Energy Code). Care must be taken for separate switches to take advantage of daylight areas through windows and skylights, divide everything into 5000 sq ft areas for the purpose of bypassing the required 7-day-programmable-timer for a maximum of 2 hrs...............the list goes on and on.
Lighting controls can become quite complicated in no time at all.

If anything, I'd suggest installing individual switches for each circuit breaker that powers lighting. This will keep the manager/clerks/hired-help out of the panel (I wonder how many times a week they shut off the cash registers or computers mistakenly )

An idle thought .....

I can ALMOST see the sense ... apart from simplicity / economy ... in using the breaker and NOT having a switch to control lights, in some applications.

The first is that HID lights, in particular, do not tolerate a casual flip of the switch.

Them there is the issue of voltage. Or, more correctly, untrained maintenance personnel. When the lights are 277 volt, you don't want the guy trying to use a 50 cent household switch ... or changing ballasts 'hot.'

Reno:
Ya I never thought of it in that way but I was thinking of how they wired my elementary and high school classrooms.. Each room had a 4 or 6 circuit panel and located where the light switches normally would be..This fed and controlled the lights obviously but also supplied the receptacle circuit(s) and exhaust fan. ( we had no such thing as A/C!..
This kept all the switching grouped nicely and also allowed the overcurrent protection to be right there in the room.. Was no need whatsoever to call the caretaker when them pesky overhead projector bulbs blew out and tripped the breaker at the same time... Also the feed to each room was no more than 30A from what I can remember so 3#10's in a piece of 1/2 would have been easy to install and cheap.
Electure: Yes I have seen where clerks / hired help / staff etc have shut off the wrong breaker and shut down something by mistake.. Happened at the community center my G/F works at but the addition of breaker " lock-dogs" solve that problem ( and so does a correct panel legend so ya know what breaker to take the lock dog off and reset

A.D

Use common sense and a calculator to decide HOW many contactor's you need. I was not saying to put all the lights in a grocery store on the same contactor. A common lighting contactor has two poles. You can light two circuits with it. if you need more, then add more. The protection is at the breaker, not the contactor. Contactors are dirt cheap these days. Material will not be the issue, only labor. If you mount an enclosure right next to the main panel for the contactors it should be a very reasonable proposition to the store owner.
I think it is important to keep store personnel out of panels anyway.

Yeah, mate,
That was what I was thinking when I made the comment above.
I didn't mean one switch/contactor = whole lighting installation.

It's permissible to use the breaker as the functional switch under British "code," but pretty rare in my experience.

Even if the main light switching point is right at the distribution panel, it's normal to fit a bank of regular switches for control alongside.

Trumpy.....No problem. We are both on the same page now.....John

Here it's pretty common... and the breakers usually don't take it that well - at some point they just refuse to stay closed.Since they always seem to blow open (mechanical failure) I'm not that worried about it.