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AFCI breaker with ferrite beads

Oldtelephoneman's picture

My son-in-laws home built in 2010 has AFCI breakers in the pannel as they should be, but two of the AFCI breakers have ferrite beads on the hot side.  One of these sets of beads hums loudly.  I have removed the beads and the circuit has not tripped for two days.  As an amateur radio op I have used ferrite beads to help remove rfi from TV inputs but does anyone know if AFCI breakers are affected by RFI? 

It's very odd that the bead (post #207575, reply #1 of 3)

It's very odd that the bead would hum (aside from not knowing the words, that is).  Seems like it would take some pretty intense current through there to cause this -- what is the load on that circuit?

(I suppose the beads are there because some CFL and LED lamp ballasts produce a current waveform that is suggestive of an arc.  But the beads would also reduce the AFCI's sensitivity to acutal arc faults, it would seem.)

Of all the preposterous assumptions of humanity over humanity, nothing exceeds most of the criticisms made on the habits of the poor by the well-housed, well-warmed, and well-fed.  --Herman Melville

AFCI breaker with ferrite beads (post #207575, reply #2 of 3)

Thanks for the reply.  I was in Texas without my tools so I could not measure current on the load.  I removed the beads and so far there seems to be no trips of this breaker.  These ferrite beads were on only two of the four AFCI breakers so I had to assume (I hate that word) they were placed to stop some kind of false trip of that breaker.


No I did not get the words to what ever it was humming either..

ferrite beads on the hot (post #207575, reply #3 of 3)

ferrite beads on the hot side

suspect the 'beads' were not ferrite, but wrapped iron, and loose cheap construction to be able to 'hum'.

Out of curiosity, what was the PN on the 'beads', or was there one?