10 gauge wiring on a 20A circuit
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10 gauge wiring on a 20A circuit
My electrician installed three receptacles which have 10 gauge runs to them. The wiring is Romex solid core. Currently, I am looking to use these receptacles as standard 110 outlets for tv/stereo off 20A breaker switches. The issue is that the breakers are tripping every time I plug something in.
Can using a heavier gauge wire cause the breaker to be tripping? Or is this a grounding/wiring issue?
I am sure my electrician will figure it out but I thought I'd ask anyhow.
Can using a heavier gauge wire cause the breaker to be tripping? Or is this a grounding/wiring issue?
I am sure my electrician will figure it out but I thought I'd ask anyhow.
#4
Need more info.
Was this wire already in place and at one time was used to power something else?
100% sure this was not used for a 220 volt appliance at one time?
Was this wire already in place and at one time was used to power something else?
100% sure this was not used for a 220 volt appliance at one time?
#7
Using #10 actually decreases the chances of the breaker tripping especially if the distance is greater then 100 feet* but most likely even then only with motor loads. The breaker is an AFCI. So it could be arching at a switch or loose connections in the wiring or anything plugged in. If anything plugged in causes it then in the wiring not the device universal motor with brushes might cause it. Unlikely such a motor would be used on a cooling fan for electronics though.
*120 volt circuits within a normal sized house are almost never over sized because of distance.
Terminology: 120 volts not 110 volts. Breaker not breaker switch. Joecaption should have written 240 volts not 220 volts.
*120 volt circuits within a normal sized house are almost never over sized because of distance.
Terminology: 120 volts not 110 volts. Breaker not breaker switch. Joecaption should have written 240 volts not 220 volts.
Last edited by ray2047; 03-31-14 at 10:13 AM.
#8
Does each of these breakers trip when you plug anything into any of the receptacles it serves?
If the item you plug in is "switched off" when you plug it in and then you switch it on, does the breaker still trip?
The AFCI breaker pictured is 20 amp and the 10 gauge wiring will work fine with it although there is overkill.
If the item you plug in is "switched off" when you plug it in and then you switch it on, does the breaker still trip?
The AFCI breaker pictured is 20 amp and the 10 gauge wiring will work fine with it although there is overkill.
#9
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The Siemens breaker will also trip on a ground fault greater than 30 ma. If so then the GND LED would light on the breaker indicating that you most likely have the ground and neutral connected somewhere.
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Thank you for all the responses so far. Here's some more background.
I am an audio nut. Many audio companies recommend 10g wire on 20A connections over 60 feet which is the case. It is supposed to help the bass frequencies. Of course this is up for debate and I will respect any opinions for or against this.
Anyhow, I just wanted to know if a heavier gauge wire could cause the breakers to trip. They are tripping even when items that are OFF are connected.
So that would indicate a ground and neutral connected somewhere?
I am an audio nut. Many audio companies recommend 10g wire on 20A connections over 60 feet which is the case. It is supposed to help the bass frequencies. Of course this is up for debate and I will respect any opinions for or against this.
Anyhow, I just wanted to know if a heavier gauge wire could cause the breakers to trip. They are tripping even when items that are OFF are connected.
So that would indicate a ground and neutral connected somewhere?
#11
So that would indicate a ground and neutral connected somewhere?
The Siemens breaker will also trip on a ground fault greater than 30 ma. If so then the GND LED would light on the breaker indicating that you most likely have the ground and neutral connected somewhere.
#12
The AFCI tripping tells me you probably have a neutral to ground fault somewhere, or your electrician didn't tighten the receptacle screws. Do you have any surge protectors or outlet strips between the receptacle and your audio equipment?
Holy crap, what amplifiers are you using?
I am an audio nut. Many audio companies recommend 10g wire on 20A connections over 60 feet which is the case. It is supposed to help the bass frequencies. Of course this is up for debate and I will respect any opinions for or against this.
#13
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You also might have a bad power strip or other device. Verify that the in wall wiring is the culprit by unplugging everything from the wall receptacles and then hook up a single two-prong device like a lamp. If turning on the lamp trips the breaker then it is great proof. If the lamp works then leave it on and plug in your other devices one at a time until the circuit trips.
#14
I really don't understand the audiophile thoughts about electricity or oxygen free copper or trying to improve the sound outside of the range of human hearing.
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I recall the electrician mentioning a shared ground. When one breaker trips, the other does a second after. Without anything plugged in I can get the breakers to stay on but any lamp, powerstrip etc will trip both simultaneously. When turning the breakers back on 2 lights illuminate - the arc light & ground light.
There are other afcis for other rooms. When I switch those off/on only the arc light comes on, not the ground light. Those outlets work fine.
There are other afcis for other rooms. When I switch those off/on only the arc light comes on, not the ground light. Those outlets work fine.
#16
Can you post some pictures?
http://www.doityourself.com/forum/el...-pictures.html
I really don't understand the audiophile thoughts about electricity or oxygen free copper or trying to improve the sound outside of the range of human hearing.
I don't, either. I think properly sized "normal" wire works fine.
http://www.doityourself.com/forum/el...-pictures.html
I really don't understand the audiophile thoughts about electricity or oxygen free copper or trying to improve the sound outside of the range of human hearing.
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Here's an image of the breakers a moment after being switched on. They are the top and bottom ones which are lit up. They stay in the on position until something is plugged in. Plugging into one outlet can make both breakers trip.
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Regarding audiophilia, it is a hobby like any other where people go to extremes in pursuit of excellence. I really went a tame route in contrast to a lot of the advice I received! If anyone is interested, here is a link to a thread where I was helped to form a plan: Electrical Considerations for New Audio Room - The Hub
#21
I am suspecting an improperly wired MWBC with a shared neutral on the single pole breakers. If that is correct there are serious issues since a single pole AFCI needs a dedicated neutral. Unless you happen to have a panel that has two pole AFCI breakers available this problem will not be easily solved without opening walls and running new cables. There might be one other option if someone miswired the wrong neutral to the breaker.
If you feel comfortable, can you tell what colors of wires are connected to the two problem breakers?
If you feel comfortable, can you tell what colors of wires are connected to the two problem breakers?
#22
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I recall the electrician mentioning a shared ground.
I have heard audiophiles report that MWBC is a bad thing but that is a different issue.
If the neutral is not shared at the panel then your electrician will need to hunt for where the grounds are connected and separate them. This can be very time consuming.
#23
I scanned the audio site above and am now wondering, what are the power requirements of this equipment that people are using more power in one room than a whole typical house? The only stereo equipment that I have seen all had 15 amp cords and lived happily in a multi-outlet strip on a 15 amp circuit.
#24
I scanned the audio site above and am now wondering, what are the power requirements of this equipment that people are using more power in one room than a whole typical house? The only stereo equipment that I have seen all had 15 amp cords and lived happily in a multi-outlet strip on a 15 amp circuit.
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So, we have a resolution. The electrician came by and swapped the AFCIs for standard breakers. He noted that AFCIs are very sensitive and can trip at the slightest issue. On standard breakers, everything is working.
#26
Many audio companies recommend 10g wire on 20A connections over 60 feet which is the case. It is supposed to help the bass frequencies. Of course this is up for debate and I will respect any opinions for or against this.
I have read various experts' opinions about the size of speaker wires. More than one expert suggests 12 gauge for runs more than 20 feet (40' round trip). To some that might be a concern if you play the sound at commercial theater levels; you have 4 ohm speakers; and the audio contains a lot of bass. Four ohm speaker circuits have lower voltage (and higher amperage) for a given number of watts and are more sensitive to voltage drop (in the speaker circuit as opposed to the amplifier AC power supply) compared with 8 ohm or greater impedance speaker circuits.
I don't think I could tell the difference in sound given 10 gauge speaker wires at 60' or even 14 gauge speaker wires at 60'
I do not expect there to be a difference in sound quality caused by normal voltage drop (less than 5%) whether the result of marginal wire size for the amplifier AC power or other cause.
Last edited by AllanJ; 04-01-14 at 02:46 PM.
#27
I do not expect there to be a difference in sound quality caused by normal voltage drop (less than 5%) whether the result of marginal wire size for the amplifier AC power or other cause.
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Speaker cables & powers cables are both part of the audiophile "bigger is better" philosophy. Not all audiophiles subscribe to this idea but it is common.
3X10 In-Wall Power
3X10 In-Wall Power
#30
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So, we have a resolution. The electrician came by and swapped the AFCIs for standard breakers. He noted that AFCIs are very sensitive and can trip at the slightest issue. On standard breakers, everything is working.
#31
To add into this, and currently running my high school's musical, I found even equipment being on different phases causes issue. However, I have not found the difference between using (150') 16/3 vs. 10/3 extension cords driving 500W RMS powered speakers. If you have equipment fed off different transformers, it will give you a good 60Hz buzz.
#32
Swapping the breakers only covered up the problem. I think that the contractor needs to come back and get to the root of the issue.
I have heard the same music thru phone wires and Monster cables and there was no discernable difference.
I have heard the same music thru phone wires and Monster cables and there was no discernable difference.
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You guys are right. I tested my equipment and I am getting a wicked buzz through the outlets. When I plug my equipment into an adjacent regular outlet the system is much more quiet.
So, what to do now? I know the electrician is going to play the "good enough" game although they admitted the AFCIs just needed to be there to pass inspection.
So, what to do now? I know the electrician is going to play the "good enough" game although they admitted the AFCIs just needed to be there to pass inspection.
#35
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I don't see why having a shared ground would cause any problems, it's a shared neutral that will trip the breakers (ground is not connected to the breaker--neutral is). An AFCI breaker senses any difference between the hot wire and the neutral wire and trips if a significant difference is detected (same principal as a GFCI outlet), which will always be the case in a MWBC. For example, if you have a lamp connected to circuit A and no load connected to circuit B, you will have X amount of current flowing on the hot wire of circuit A and an equal amount of current traveling on the shared neutral. Since there is no current flowing in circuit B's hot wire, circuit B's AFCI breaker will sense the imbalance between its hot wire and the shared neutral and therefore trip. Even if you had identical balanced loads on circuit A and circuit B, the breakers will still trip because the current on the shared neutral is the sum of the currents of circuit A and circuit B so there will always be an imbalance. Seems like your only options are to either use standard breakers (against code) or pull another circuit (PITA).
#36
I know the electrician is going to play the "good enough" game although they admitted the AFCIs just needed to be there to pass inspection.
#37
To add into this, and currently running my high school's musical, I found even equipment being on different phases causes issue. However, I have not found the difference between using (150') 16/3 vs. 10/3 extension cords driving 500W RMS powered speakers. If you have equipment fed off different transformers, it will give you a good 60Hz buzz.
The hot(s) and neutral coming off the load side of an AFCI or GFCI may not be interconnected with hots or neutrals originating elsewhere in the electrical system. Therefore the hot and neutral coming off the load side of a single pole AFCI or GFCI may not rejoin a multiwire branch circuit that may have supplied that AFCI or GFCI.
#38
A shared ground should have no part in the normal operations of a circuit. It is there in the event of a fault and normally sits there and does nothing. When it does do something it is only for a few seconds or less.
#39
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A shared ground should have no part in the normal operations of a circuit. It is there in the event of a fault and normally sits there and does nothing. When it does do something it is only for a few seconds or less.
Current only travels on the hot and the neutral (unless there is a ground fault of course). Any imbalance between the current on the hot and the current on the neutral will trip the AFCI breaker. In the OP's case, and in a MWBC in general, there will always be an imbalance.
I need to correct myself:
...the current on the shared neutral is the difference between the current of circuit A and circuit B
#40
The AFCI is looking for an arcing signature from a loose connection or from a broken conductor. I would still like to see pictures to confirm suspicions.