AFCI BREAKER SEPARATION

[RICHARD TAN]

Hi Jerry,

Electrical panel. Is it true that on the new NEC? AFCI breaker in the electrical panel required to be separated with other non AFCI bearker. I did a thermal scan on many AFCI breaker, I found many AFCI breaker temperature of 100F-104F. Is the AFCI breaker separation is to keep the breaker cooler? I have found only one electrical panel that was install this way on a newer home (2010), non in older home. Is this the new way to install AFCI breaker?

Thank's Richard

[Jerry Peck - Codeman]

Hi Richard,

I will double check on that for you - if it is an 'NEC requirement' then I missed it.

Even though the various manufacturers have acknowledged the heat generated by AFCI breakers, and many verbally recommended separating the older AFCI breakers, they did not put that in writing.

Supposedly, the new AFCI breakers do not generate enough heat for that to be a problem. As such, there has been no requirement for separating AFCI breakers in a panel.

[Jerry Peck - Codeman]

Hi Richard,

As I thought, I could not find anything in the NEC regarding spacing AFCI breakers. This would be because each manufacturer would require that if their AFCI breakers produced too much heat to be installed side-by-side.

If one manufacturer did not require it and another manufacturer did, the manufacturer requiring that spacing would like be at a disadvantage in the marketplace.

You would need to read the installation instructions on the AFCI breaker to find out if there was any limitation regarding the installation of that particular manufacturer's AFCI breakers.

[Marc M]

AFCI's and GFCI's are ALWAYS hotter than other disconnects when you scan via infrared.

[Jerry Peck - Codeman]

AFCI's and GFCI's are ALWAYS hotter than other disconnects when you scan via infrared.

Hi Marc,

GFCI breakers too?

Are you sure? I can't think of what would cause a GFCI breaker to be hotter.

[Marc M]

Yes you're correct. The afci disconnects and its GFI receptacles which show hotter. I mis spoke.

[Jerry Peck - Codeman]

its GFI receptacles which show hotter

Hi Marc,

I just cannot think of a reason why a GFCI protection device would show hotter than a similar non-GFCI protection device. The GFCI protection device does not use any voltage or current in the normal 'all is okay' mode - the GFCI protection device does not use any more current in the protection 'all is not okay' mode as it is getting ready to trip (which happens immediately when the threshold is reached). The GFCI protection device does, in the 'all is not okay' mode, actually create a very (and I do mean very) minute amount of current, but not enough to be measurable as far as heat goes, and the time from of that minute amount of current is quite brief too.

An AFCI protection device, on the other hand and as compared to a GFCI protection device, does use a small amount of power (current/voltage) to run its small inboard computer to monitor the circuit at all times. It is that small power used which does generate the heat which causes AFCI protective devices (i.e., AFCI breakers) to heat up. The AFCI breaker definitely heats up enough to see it with an infrared thermal imaging camera.

But a GFCI protective device heating up? That needs to be explained to me so I can figure out and understand what is going on which shouldn't be going on.

[Marc M]

Yea, I agree. I will scan one for you and send it. I see many IR reports where the tech will call out the GFI receptacle for this very reason. Anyhow, let em scan one and I'll shoot one over to you.

[Marc M]

Here's a few from my house. I have 5 and all were fairly warm.

[Marc M]

Wudda ya think?

[Jerry Peck - Codeman]

Ummm ... somehow my response is gone ... maybe I went to edit it and deleted it?

I will have to type it again this evening.

[Marc M]

No worries...take your time.

[Jerry Peck - Codeman]

Hi Marc,

Not sure what happened to my other post like this one, maybe I clicked 'Preview' instead of 'Submit', regardless, I am sure it was something I did and just did not catch it at the time - oh well.

What I had posted ... er ... thought I had posted ... was that I was asking if you would try to see what was actually hot and why.

For example, could you:
- remove that receptacle and take an image of each side and its back
- remove any conductors feeding off to downstream receptacles (to remove any load on the receptacle's terminals and to remove any current flow to/through the receptacle, then take images of the front, both sides, and the back
- with no other conductors other than the line connected to the receptacle, remove:
- - the ground and take images
- - the neutral and take images
- - the hot and take images

At some point that heat which is showing will go away, and depending on what is no longer connected and what is still connected will indicate what might be generating the heat. The simplest thing would be that it is heat from a load wired downstream from that receptacle and the current is heating up a terminal or something.

Will be interesting to have you tell me what you find out.

[Marc M]

I'll give it a shot this weekend, we'll see what happens.