Latest Discussions : Electrical & Lighting


07:23PM | 01/17/06
Member Since: 01/17/06
2 lifetime posts
I am new to home owning and electricity but know a little. I have a new home with the special circuit breakers for the upstair bedrooms that trips if an old lamp is plugged into them - modern safety protection. Both upstairs bedroom breakers tripped, so we unplugged everything. We reset them and they tripped again. We still had power to an upstairs hallway lamp that is old. After unplugging that hallway lamp upstairs, the circuit breakers didn’t trip again.

The question: Would the hallway socket be getting power through these special circuit breakers and through someplace else? So when the lamp blew the breakers for the bedrooms, it remained on, getting power from a different breaker that wasn’t being blown?

Second question: If that is the case and there are two wires bringing power to the hallway lamp, wouldn’t that defeat the purpose of having the special breakers that detect old lamps?

We have unplugged the lamp and no longer have problems but are very confused as to why the lamp, if it was blowing the circuits would still have power.

Any advice would be great.


04:04AM | 01/18/06
Member Since: 04/25/05
1915 lifetime posts
By special breaker do you mean an Arch Faul Circuit Interrupter.

By code starting in 2000 bedrooms have had to be wired this these type of breakers, however some areas are not requiring them or the starting date is later.

Halls and other rooms do on need to be on those circuits, however, in some caes it is convient to use the bedroom behind for the hall receptacle.

AFCI's not only trip on overloads (as to normal breakers), but also on paralllel arcing faults and leakage currents. The arcing fault is one where the wire are touching or insulation is worn and it can have short spikes of current, but to fast to trip on an overload. It is possible that the lamps do have this, but you would have probably noticed them flickering.

Leakage currents are where all of the current from the hot wire does not return through the neutral. It is similar to a GFCI, but the level of fault is much higher as it is designed to detect bad insulation, not to prevent shocks. Now lamps normally trip on leakage as most of them don't have a ground wire and there is no place for any leakage current to flow.

What really sounds odd is that, if I understand correctly, that 2 different AFCI's tripped from ONE LAMP.

If that is the case it sounds like it was miss wired using either a multi-wire circuit or the neutrals are combined at some point.

If that is the case then any lamp in that receptacle will cause them to trip.

If that is the case then you need to get an electrican to check it out.

If this is a new, new house contact the builder.


05:15AM | 01/18/06
Member Since: 01/17/06
2 lifetime posts
Thank you for the info billhart. That is exactly what they are - AFCIs.

Here is my confusion, (and it sounds like I may have to have an electrician come out.) The breaker box has two of them; one for the two small upstairs rooms, and one for the master suite. Both were being blown when the lamp in the hallway was plugged in.

When the lamp in the hallway would blow them, all bedrooms upstairs would lose power (of course) but the lamp that blew the AFCIs would continue to have power.

That is why it took us so long to figure out what was causing them to trip.

Ever since the lamp was removed - no more problems.

Is it common to run electricity this way, or should an electrician come out and take a look? (The house is 2 years old).


05:50AM | 01/18/06
Member Since: 04/25/05
1915 lifetime posts
The hall receptacle should either be on a separate circuit so that it does not affect the AFCI or the receptacle should shut off when the AFCI trips.

When you call an electrican ask for one that does trouble shooting and not just new construction.


11:02AM | 02/03/06
Member Since: 02/02/06
2 lifetime posts
sounds like the two AFCI bedroom circuits and the hall circuit are sharing a neutral. This could explain why the bedroom circuits both trip, but the hall circuit (not AFCI) stays on. Make sure the breakers are installed and wired correctly.

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