Dual function Afci/Gfci issue

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mspicka

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I have a mixture of a ceiling fan, 11 recessed 4" wafer lights and 4 outdoor lanterns with 60w incandescent lamps on a single 15a dual function breaker and when I screw in more than one incandescent lamp the breaker trips. I changed the bulbs to led and it solves the problem.

The lady wants the incandescent bulbs because she likes the look of them. Is this as simple as a bad breaker? Eaton BR...
 
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mspicka

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Looks like this one. I didn't look too close to see if it had any extras.
 

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synchro

synchro

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mspicka said:
I have a mixture of a ceiling fan, 11 recessed 4" wafer lights and 4 outdoor lanterns with 60w incandescent lamps on a single 15a dual function breaker and when I screw in more than one incandescent lamp the breaker trips. I changed the bulbs to led and it solves the problem.
Click to expand...

Just guessing, but one thing that might cause this is some unwanted resistance between the neutral and EGC on the load side of the home run. The more load current there is from incandescent lamp loads, the more voltage drop there will be along the neutral conductor and therefore more voltage across a N-G resistance. This increased voltage across the resistance would cause a higher N-G leakage current, and if it exceeds 6 mA it could trip the GFCI function of the breaker.

There is a grounded neutral detection function in GFCI's, but it's only required to trip when there's a very low N_G fault resistance, typically less than a few ohms. But, for example, if you had a 0.25V drop on the neutral conductor and a 40 ohm N-G resistance, that would cause over 6 mA of leakage current and trip the GFCI.

One suggestion is to try a GFCI only breaker and see if it still trips. If it does trip, then with all loads switched off and the breaker off, you might remove the load neutral from the breaker and then measure the resistance between the neutral and EGC. It should be a very high resistance / open circuit.
 
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AC\DC

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synchro said:
Just guessing, but one thing that might cause this is some unwanted resistance between the neutral and EGC on the load side of the home run. The more load current there is from incandescent lamp loads, the more voltage drop there will be along the neutral conductor and therefore more voltage across a N-G resistance. This increased voltage across the resistance would cause a higher N-G leakage current, and if it exceeds 6 mA it could trip the GFCI function of the breaker.

There is a grounded neutral detection function in GFCI's, but it's only required to trip when there's a very low N_G fault resistance, typically less than a few ohms. But, for example, if you had a 0.25V drop on the neutral conductor and a 40 ohm N-G resistance, that would cause over 6 mA of leakage current and trip the GFCI.

One suggestion is to try a GFCI only breaker and see if it still trips. If it does trip, then with all loads switched off and the breaker off, you might remove the load neutral from the breaker and then measure the resistance between the neutral and EGC. It should be a very high resistance / open circuit.
Click to expand...
Would not the LED inrush do the same thing? I don't know if the inrush would equate to what an equivalent incandescent wattage would of been.
Would the Inrush happen so fast that the GFCI would not detect?
 
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Jovita912Stackhouse

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Be safe, and make sure that you are using the right type of light bulb for the fixture you are using. If you are using a ceiling fan light fixture, then use a fan-rated bulb. If you have recessed lighting, you will need to use a LED or CFL bulb. Led bulbs are a bit more expensive, but they will last much longer and use a lot less energy. Incandescent bulbs also get hot, which can be a fire hazard when used in a ceiling fan, so you should also consider using a fan bulb.
 
synchro

synchro

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AC\DC said:
Would not the LED inrush do the same thing? I don't know if the inrush would equate to what an equivalent incandescent wattage would of been.
Would the Inrush happen so fast that the GFCI would not detect?
Click to expand...

UL943 requires a GFCI to trip in no more than a time T = (20/I)1.43 seconds, where I is in milliamps. That would allow, for example, up to 100 mA of leakage for 0.1 seconds before it trips (although apparently it's significantly less than this in typical devices).
From what I can gather, the inrush current in a 60W bulb could last a few cycles of 60 Hz, whereas the inrush of a typical LED bulb would last a small fraction of a cycle.

https://voltage-disturbance.com/lighting-power-quality/incandescent-lamp/
http://www.olino.org/blog/us/articles/2013/10/22/inrush-current-for-led-light-bulbs
 
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mspicka

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Jovita912Stackhouse said:
Be safe, and make sure that you are using the right type of light bulb for the fixture you are using. If you are using a ceiling fan light fixture, then use a fan-rated bulb. If you have recessed lighting, you will need to use a LED or CFL bulb. Led bulbs are a bit more expensive, but they will last much longer and use a lot less energy. Incandescent bulbs also get hot, which can be a fire hazard when used in a ceiling fan, so you should also consider using a fan bulb.
Click to expand...
These lightbulbs came with the lanterns and the customer wants to use them because they look cool. I tried to get her to change to led. I'm going to change the breaker and go from there.
 
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