
Originally Posted by
kwired
A breaker with more load on it will be "hotter" then others that don't have as much load, especially if the load is fairly continuous.
Does sound like possibly some solid state controlled heating circuit could be the source of such rapid cycling. Contactor controlled loads won't hold up to that kind of cycling.
Trace down these circuits - if they are feeders you need to find the associated branch circuit(s) that are taking such current that is being questioned to find out what is going on.
It might be more then one load involved but by the time you get to feeder level they add up to a fairly significant amount. Office tower - probably lots of laser printers in there - their "heaters" cycle frequently. Maybe not every second on an individual machine but put several in a large building and you will have constantly fluctuating load at feeder levels.
Copy machines too... I once did a legal office, I saw this exact thing and another electrician suggested it was the copy machines, they had 8 of them in a 30 room building! I unplugged them all, the issue went away, plugged them back in, current draw was high for the first 5 minutes, then started cycling like this again.
__________________________________________________ ____________________________
Many people are shocked when they discover I am not a good electrician...
Bookmarks