Random Trips when HVAC kicks on

[Fred B]

View attachment 2555126

What is that neutral just hanging out at bottom?

I seriously doubt that the transformer is your problem but it absolutely needs to be replaced with the proper one.

From your saying that you hear the fan "ramp up", it would indicate a VFD which are notorious for messing with AFCIs and GFCIs.

-Hal

Excuse me, not overly familiar with VFD just the basics, If I am to understand what you're saying and it's relationship to the OP issue, the VFD causes a potential harmonic that will intermittently trip the AFCI. Would I be correct to assume, for it to be random as OP indicated most likely the circuits tripping had some form of load at the time the VFD activated, otherwise there would be no appearance (from AFCI or GFCI perspective) of an imbalance. No load no Arc or ground fault. Is this a correct assumption? Or is there some other action at play?

 

[hbiss]

Would I be correct to assume, for it to be random as OP indicated most likely the circuits tripping had some form of load at the time the VFD activated, otherwise there would be no appearance (from AFCI or GFCI perspective) of an imbalance. No load no Arc or ground fault. Is this a correct assumption? Or is there some other action at play?

AFCIs don't look for an imbalance, just the waveform of the voltage. So I wouldn't think loads would make any difference though it's impossible to say because nobody knows the design of AFCIs. It just may be that capacitive coupling between the conductors in the panel plays a part or RF radiated from the VFD circuit wiring in the panel into other AFCIs but who knows.

-Hal

 

[Baxter83]

What is that neutral just hanging out at bottom?

It was being used on a afci/gfci breaker that didn't have the snap in neutral. It got taken out once all was resolved and actually done.

 

[kwired]

It was being used on a afci/gfci breaker that didn't have the snap in neutral. It got taken out once all was resolved and actually done.

In meantime you had no GFCI/AFCI protection, and if you landed the circuit neutral on the breaker you had an open circuit and nothing worked at all. Thermal mag function of the breaker still works though.

 

[Baxter83]

In meantime you had no GFCI/AFCI protection, and if you landed the circuit neutral on the breaker you had an open circuit and nothing worked at all. Thermal mag function of the breaker still works though.

The breaker that used it wasn't in the panel. The wire was cut in the meantime instead of removing breakers blocking the lug where it was landed in the picture. All was well

 

[kwired]

The breaker that used it wasn't in the panel. The wire was cut in the meantime instead of removing breakers blocking the lug where it was landed in the picture. All was well

Makes sense now.

 

[drcampbell]

... I currently don't have a 3rd party photo thingy.

https://postimages.org/ is easy to use, and free.