Relay excessive switchinbng/arcing

Is the signal that the arcy sparky thing solid on or off? That can lead to relay "chattering" Check your wiring to the coil, see if it is intermittant. If so fix the cause then replace the relay.

Shorting meaning short circuit is a fault condition and is likely to cause the overcurrent device to open.

Another possibility is that it is just humming and staying closed - no arcing. You may know it is arcing in which case this is irrelevant. Some posters hear a noise and guess what is happening. Some humming is normal on an AC relay. Loud humming may be caused by the armature not making a tight connection with the coil. Hum is a pretty constant 120Hz.

Does the boiler work? Is the noise new? Did you look at the voltage on the coil? AC or DC coil supply?

bud--

Pop

: : Does the boiler work? : Is the noise new? : Did you look at the voltage on the coil? : AC or DC coil supply? : : bud--

This could be OT, I have a relay in my boiler which buzzes/arcs. I'm trying to diagnose the fault, probably in my wiring. What conditions (eg shorting) would cause a relay to switch on & off very rapidly (leading to a buzzing noise) & arc? Many thanks Jonathan

Some AC relays use a split armature with a shorting ring on one part of the split to cause a slight phase shift and smooth out the forces. Also, magnetic dust can build up inside a relay and keep the armature from fully closing. Bill Kaszeta Photovoltaic Resources Int'l Tempe Arizona USA snipped-for-privacy@pvri-removethis.biz

THanks you guys,

I think I have forund my answer from another NG - & have started isolating components.

Cheers J>>