Mike, here's the article from the ARRL, Jim
You might find this interesting.
From today's ARRL newsletter
Your League: ARRL Helps Manufacturer to Resolve Arc Fault Circuit
Interrupter RFI
Problems
The ARRL Lab has worked with a manufacturer of arc fault circuit interrupter
(AFCI)
breakers to resolve complaints that Amateur Radio RF was causing certain
breaker
models to trip unnecessarily. Like the more common ground fault circuit
interrupter
(GFCI), the AFCI is a safety device. Primarily designed to detect problems
that could
result in a fire, AFCIs detect potentially hazardous arc faults that result
from
often unseen damage or poor connections in wiring and in extension cords and
cord
sets.
"Several months ago we started receiving reports from amateurs that when
they transmitted,
their AFCI breakers were tripping," said Mike Gruber, W1MG, the ARRL Lab's
EMC specialist.
He noted that the issue has been a topic of online ham radio discussions as
well
as on homeowner sites; it seems that stray RF is not the only thing that can
cause
a "nuisance trip" of an AFCI. Gruber pointed out that the National
Electrical Code
(NEC) already requires AFCIs in some household circuits, but not all US
jurisdictions
have adopted the requirement.
W1AW Station Manager Joe Carcia, NJ1Q, with the AFCI test stand. [Mike
Gruber, W1MG,
photo]
Gruber said that as AFCIs became more common in new construction in the US,
reports
started coming in that AFCIs in the vicinity -- not just in the radio
amateur's home
-- would trip in the presence of RF from an Amateur Radio transmitter. While
each
manufacturer's design is proprietary, most AFCIs detect arcs by monitoring
the shape
of the alternating current waveform, changes in current levels, voltage
irregularities,
and the presence of high frequency emissions or "noise." The ARRL Lab dug
into the
problem.
"Last summer we built a test fixture in which we could test any type of
circuit breaker,"
Gruber said. It involved using W1AW as an RF source. Gruber said he bought
one of
"every AFCI that I could get my hands on," but when the Lab began testing
them during
W1AW transmissions, none of the devices tripped.
A ham in New Mexico who had reported AFCI problems sent some of his breakers
to the
ARRL Lab, "and those tripped when we tested them," Gruber said. The
problematic breakers
were certain models made by Eaton Corporation. "We already had an Eaton
breaker,
an older model, but it did not trip," he noted, adding that the breaker had
a yellow
button. The newer model, which had a white button, did trip in the presence
of RF,
however, even at power levels down to about 50 W on 17 meters.
Gruber contacted Eaton, and two of the manufacturer's engineers visited ARRL
Headquarters
in August. "Eaton was extremely cooperative and eager to resolve this,"
Gruber recounted.
"They spent the day with us, going over our test methods and took some of
the problematic
breakers back with them, eventually developing a modified version.
"We have just finished testing the new version of the breaker, and it did
not trip
during W1AW transmissions and in other tests," Gruber reported. He said the
new breaker
is still in the queue for UL approval.
Eaton Engineering Director Andy Foerster said arc fault detection is
challenging,
in part because so many common household devices -- such as vacuum cleaners
and power
tools that use motors with brushes -- create arcing. In information provided
to ARRL
Eaton engineer Lanson Relyea said that because AFCIs rely on HF emission
detection
to verify arcing, "any signal that conducts or radiates a signal within the
detection
band of the AFCI can cause interference and cause the device to trip without
the
presence of a true arcing condition."
Eaton and ARRL agreed that when the manufacturer comes out with any new
models of
breakers, it will ask the League to test them at W1AW. "It's a win-win
situation,"
Gruber said. Eaton also has agreed to work with anyone having a problem with
RF tripping
its AFCIs.
Hams experiencing unwanted tripping problems with their or their neighbors'
AFCIs
should first contact the manufacturer. In the case of Eaton breakers,
contact
Bob Handick
(
412-893-3746
) or
Joe Fello
(
412-893-3745
). Read
more
.
-----Original Message-----
From: Michael Ryan
Sent: Wednesday, July 16, 2014 5:49 AM
To: [log in to unmask]
Subject: Ground Falt Circuit Interupt Breaker Sensativity to RF
Hi all:
Up here in Canada, according to the electrical code, circuit breakers for
bedrooms have to be a ground fault circuit interrupt type (GFCI).
They're meant to trip quick enough to prevent shock to children when they
stick there fingers and other objects in the outlet or accidents to persons
using an Electric blanket or waterbeds and so on.
Well when we had our cottage wired, my Uncle in law, who did the electrical,
didn't listen to me with regards to wiring up the spare room as a radio room
but as a spare bedroom and basically put the 2 outlets on the master's
outlets and connected them all up to the GFCI breaker in the Panel.
Each time I'd key my radio on this breaker, I'd trip it and this would occur
on the antenna and not on the dummy load. It got to the point where I had to
have the connection changed.
We now have the bedrooms on a non GFCI and the GFCI hooked up to the dining
room outlet which isn't used and is in fact off.
However, when turned on, this breaker would still trip when I'd transmit on
my antenna and not on the dl. So at the end of the day, we just have it
turned off.
I'm wondering if my electrical's ground wires could be the length of an
antenna and are in fact acting like a receive antenna and is causing that
breaker to trip? How would it behave differently if the antenna was a wire
antenna at 45 feet?
My vertical is probably 40 feet or so away from the electrical grounding
system but is on the same side. . I have all my equipment properly grounded
into 3 5 foot ground rods, driven down to there tops outside the shack.
Funny though, plug an electrical appliance such as a toaster into one of the
outlets on the GFCI, it won't trip. Even though the toaster is an 800W
appliance. My FT-102 only draws 5 amps and makes 200W and will cause this
breaker to trip almost immediately.
73:
Mike VO1AX
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