tripping breaker

[treyp3]

Had a call from a landlord today, 15 amp arc fault breaker tripping, flat screen TV fried. Tenant says breaker trips once a week for the year she has been there. Last night it tripped and she reset it, then noticed TV smoking. She unplugs the TV and the breaker trips 5 more times. Working fine when I got there.Checked 3 way switches for shared neutrals, checked connections at breaker, pulled receptacles, amp probed circuit at panel. She doesn't notice any pattern to the tripping (like when she uses the vaccum). Pluged in a bunch of stuff, got it up to 22 amps before it tripped. Left the circuit pulling about 10 amps for about 2 hours and still no tripping (whent out to get a 15a Sq D QO arc fault and took a long lunch). I replaced the arc fault breaker and left the TV unplugged. I felt that maybe the TV was going bad and was the culprit all along. The new breaker held for about six hours and tripped again. I cant figure what would fry a TV and not trip for for 6 hours. I told her todays fix may not repair the problem but that it was a good start. Now I have to go back tomorrow, any suggestions where to start?

 

[meternerd]

Had a call from a landlord today, 15 amp arc fault breaker tripping, flat screen TV fried. Tenant says breaker trips once a week for the year she has been there. Last night it tripped and she reset it, then noticed TV smoking. She unplugs the TV and the breaker trips 5 more times. Working fine when I got there.Checked 3 way switches for shared neutrals, checked connections at breaker, pulled receptacles, amp probed circuit at panel. She doesn't notice any pattern to the tripping (like when she uses the vaccum). Pluged in a bunch of stuff, got it up to 22 amps before it tripped. Left the circuit pulling about 10 amps for about 2 hours and still no tripping (whent out to get a 15a Sq D QO arc fault and took a long lunch). I replaced the arc fault breaker and left the TV unplugged. I felt that maybe the TV was going bad and was the culprit all along. The new breaker held for about six hours and tripped again. I cant figure what would fry a TV and not trip for for 6 hours. I told her todays fix may not repair the problem but that it was a good start. Now I have to go back tomorrow, any suggestions where to start?

Are all neutrals tight? AFC's don't like loose connections, so that's where I'd look first.

 

[jxofaltrds]

Sounds like she wants a new TV!

Edit:

Ask SD if you could reset that breaker 50+ times.

 

[cadpoint]

I beleive with an Ideal circuit tester you could trace a line, my bet; circuit in wall cavity
and has opened up or was near rubbed open with air duct. Combination of wire just nicking
Circuit and temp different makes it move...

The AFCI is doing what it is suppose to. Turn on A/C, Turn on heat gun, pop circuit,
sell new circuit.

Got a meggar, can you rent one? U have to clear everything off circuit! Test, sell circuit.

Turn on A/C, Turn off circuit, check grill for voltage. turn on circuit, check grill for voltage,
maybe turn on heat gun, sell new circuit

That will be .05 cents please :huh:

Oh yeah, like other already said, Tighten up....

 

[treyp3]

Sounds like she wants a new TV!

Edit:

Ask SD if you could reset that breaker 50+ times.

First thing I did was check the connections at the panel, then checked all the 3 ways for shared neutral. Whoever trimmed this place did a good job. Every terminal was really tight and every joint looked text book. She was pretty pissed when I said I thought it may be the TV. She acted like I may not know what I'm doing, I'm wondering if she's gunning for a new TV myself. She tells me she reset the breaker 5 times plus once a week for a year, I figure it was probably fine, but was concerned enough to replace it.

 

[growler]

I replaced the arc fault breaker and left the TV unplugged. I felt that maybe the TV was going bad and was the culprit all along. The new breaker held for about six hours and tripped again. I cant figure what would fry a TV and not trip for for 6 hours. I told her todays fix may not repair the problem but that it was a good start. Now I have to go back tomorrow, any suggestions where to start?

You left the TV unplugged but were you there when the breaker tripped again? If you were not there I would think the lady plugged up the TV (maybe).

I would use an extension cord and connect the TV to a different circuit while looking for other problems.

Map out this circuit and find out what else was on at the time of the breaker tripping. Anything from a ceiling fan to a vacuum cleaner if it was on this circuit.

I always look for the quick and easy things that may be responsible and get to the serious trouble-shooting later.

 

[cadpoint]

Is the TV a three prong plug? If not, you could get a dougnut at Sears up to 15 Amps and read what the TV's drawing? ...

 

[treyp3]

I beleive with an Ideal circuit tester you could trace a line, my bet; circuit in wall cavity
and has opened up or was near rubbed open with air duct. Combination of wire just nicking
Circuit and temp different makes it move...

The AFCI is doing what it is suppose to. Turn on A/C, Turn on heat gun, pop circuit,
sell new circuit.

Got a meggar, can you rent one? U have to clear everything off circuit! Test, sell circuit.

Turn on A/C, Turn off circuit, check grill for voltage. turn on circuit, check grill for voltage,
maybe turn on heat gun, sell new circuit

That will be .05 cents please :huh:

Oh yeah, like other already said, Tighten up....

What do you mean by AC grill? What would I be touching leads to? Do you mean in the air handler?

 

[treyp3]

You left the TV unplugged but were you there when the breaker tripped again? If you were not there I would think the lady plugged up the TV (maybe).

I would use an extension cord and connect the TV to a different circuit while looking for other problems.

Map out this circuit and find out what else was on at the time of the breaker tripping. Anything from a ceiling fan to a vacuum cleaner if it was on this circuit.

I always look for the quick and easy things that may be responsible and get to the serious trouble-shooting later.

I was long gone when it tripped again. I doubt she plugged the TV back in. When I was there I plugged in the TV. It is a flat screen. When plugged in it would try to come on and make a small popping noise then shut off, then try to come on then pop and off. It did this on its own over and over when left plugged in. I put an amp probe back at the panel during this and it would jump up about an amp and a half every time it tried to come on. She saw this with me standing there so I doubt she plugged it back in. This circuit is general lighting for a living room, plugs and 1 fan/light, plus 1 dining room light and 1 kitchen fluorescent light. When she called to say it tripped again she told me no vacuum or anything plugged in, just fan/light and dine light.

 

[RLyons]

Shot in the dark, stray voltage on the coax....the arc breaker would pick that up if the tv/or cable box was plugged into the circuit, no?

 

[growler]

I was long gone when it tripped again. I doubt she plugged the TV back in. When I was there I plugged in the TV. It is a flat screen. When plugged in it would try to come on and make a small popping noise then shut off, then try to come on then pop and off. It did this on its own over and over when left plugged in. I put an amp probe back at the panel during this and it would jump up about an amp and a half every time it tried to come on. She saw this with me standing there so I doubt she plugged it back in. This circuit is general lighting for a living room, plugs and 1 fan/light, plus 1 dining room light and 1 kitchen fluorescent light. When she called to say it tripped again she told me no vacuum or anything plugged in, just fan/light and dine light.

Once you have eliminated the TV as a probable cause then it could be almost anywhere in the circuit.

It could be a hard one to find. A fan motor could be bad or producing enough vibration for an arc at a loose connection.

If it's going to take a number of hours for the breaker to trip you may need to disconnect a part of the circuit so as to eliminate a little more and try to isolate the problem.

It may turn out that the TV going bad was just a coincidence.

 

[treyp3]

Once you have eliminated the TV as a probable cause then it could be almost anywhere in the circuit.

It could be a hard one to find. A fan motor could be bad or producing enough vibration for an arc at a loose connection.

If it's going to take a number of hours for the breaker to trip you may need to disconnect a part of the circuit so as to eliminate a little more and try to isolate the problem.

It may turn out that the TV going bad was just a coincidence.

Turns out flickering fluorescent lamps can trip arc faults!

 

[glennspark]

Had a call from a landlord today, 15 amp arc fault breaker tripping, flat screen TV fried. Tenant says breaker trips once a week for the year she has been there. Last night it tripped and she reset it, then noticed TV smoking. She unplugs the TV and the breaker trips 5 more times. Working fine when I got there.Checked 3 way switches for shared neutrals, checked connections at breaker, pulled receptacles, amp probed circuit at panel. She doesn't notice any pattern to the tripping (like when she uses the vaccum). Pluged in a bunch of stuff, got it up to 22 amps before it tripped. Left the circuit pulling about 10 amps for about 2 hours and still no tripping (whent out to get a 15a Sq D QO arc fault and took a long lunch). I replaced the arc fault breaker and left the TV unplugged. I felt that maybe the TV was going bad and was the culprit all along. The new breaker held for about six hours and tripped again. I cant figure what would fry a TV and not trip for for 6 hours. I told her todays fix may not repair the problem but that it was a good start. Now I have to go back tomorrow, any suggestions where to start?

well...

for a start i`d be identifying which OPD fed what....thats your start.

then you move on to insulation testing...now, i dont know as yet what the NEC says (as i havn`t read through it all yet)...but will take BS7671 as my que:

so you get an insulation resistance tester and test between all live conductors...and all live conductors and earth....you are looking for a min of 1 meg...

dont know if this helps.
glenn.

PS:

unplug/disconnect anything that may be effected by the dilectric strength test beforehand....this would include variable resistors (dimmers) sensors and PIRs...

 

[glennspark]

well...

for a start i`d be identifying which OPD fed what....thats your start.

then you move on to insulation testing...now, i dont know as yet what the NEC says (as i havn`t read through it all yet)...but will take BS7671 as my que:

so you get an insulation resistance tester and test between all live conductors...and all live conductors and earth....you are looking for a min of 1 meg...

dont know if this helps.
glenn.

PS:

unplug/disconnect anything that may be effected by the dilectric strength test beforehand....this would include variable resistors (dimmers) sensors and PIRs...

i also forgot to mention that continuity should be verified first on any circuit being subjected to testing (IR) to ensure that the whole circuit is tested.....

 

[suemarkp]

My flat screen "went bad" in a similar fashion. First, I replaced the power strip it was plugged into and that fixed it for 3 months. But it started doing it again (trying to come on, only to power off and repeat the power on sequence). I replaced the TV power cord and now all is well. If you have a frayed wire in the TV power cord, I wonder if the arc fault will pick that up. I don't have any arc fault breakers in my house so I don't know if that would be common.

 

[glennspark]

it sounds like a voltage drop it may be down to the lead...but check the outlets

is it a ring final?...or a radial?

 

[glennspark]

My flat screen "went bad" in a similar fashion. First, I replaced the power strip it was plugged into and that fixed it for 3 months. But it started doing it again (trying to come on, only to power off and repeat the power on sequence). I replaced the TV power cord and now all is well. If you have a frayed wire in the TV power cord, I wonder if the arc fault will pick that up. I don't have any arc fault breakers in my house so I don't know if that would be common.

you must have an OPD limiting current top end..

 

[1793]

Turns out flickering fluorescent lamps can trip arc faults!

So, was this your problem?

 

[kwired]

My flat screen "went bad" in a similar fashion. First, I replaced the power strip it was plugged into and that fixed it for 3 months. But it started doing it again (trying to come on, only to power off and repeat the power on sequence). I replaced the TV power cord and now all is well. If you have a frayed wire in the TV power cord, I wonder if the arc fault will pick that up. I don't have any arc fault breakers in my house so I don't know if that would be common.

If the power supply cord also contains a DC power supply like many LCD TV's do, then any damage to the supply side maybe effects the AFCI, but if on the DC side I highly doubt it will matter to the AFCI, but would still be a problem for operation of the TV.

 

[suemarkp]

you must have an OPD limiting current top end..

No, the bad wire or poor connection in the cord was limiting my current.

Oh, and we don't do ring circuits here, I don't think that would be allowed by our code.