smokes go off when loads are turned on???

[jay80424]

Hello there,

Hopefully this is the right forum.

I have a house we just did an addition to. Prior to the addition, we had a loft, and in that loft was (is) a small theater with a projector, surround sound system, and a 300 watt halogen torche light. Everything worked fine, and the only thing I ever noticed voltage wise was when all the AV gear was on, the voltage lights on the surge protector went from 115v to 110v.

Fast forward to the addition being done. 5 smoke detectors were added per code, and it is my understanding that they were all wired to the same loft circuit that the first one is on. These are line voltage smokes with battery back up. No other loads were added to this loft breaker.

Now when the surround soud and projector is on, along with the torche lamp, all the smoke detectors go off. If I lower the dimmer on the torche light (this is a lutron dimmer, that actually reduces the load via a triac), the smokes stop.

I assume that the smokes are reacting to a lower than accecptable voltage on the line (although I don't understand why as they have battery backup).

I have not had a chance to put a meter on the circuit to dee exactally what the voltage drop really is, but I will tomorrow.

Any ideas where to start troubleshooting this? As you can imagine, it's pretty annoying.

Thanks in advance

 

[quogueelectric]

I think the popcorn is burning waiting for the movie to start.

 

[480sparky]

Are the smokes on their own circuit? Try swapping the circuit to another one on another phase or leg.

 

[jay80424]

I think they are on the loft circuit. I Can turn on every load in the house and the smokes don't go off. but if I turn on the loft all by itself, they do go off.

 

[benaround]

jay, 115v to 110v is a 4.5% voltage drop, and that's just with some LED lights. See what

kind of voltage you are getting when they go off. Sounds like you need to put the smokes

on another circuit, or some of the A/V stuff on a seperate circuit.

 

[quogueelectric]

See which one is reading an alarm. One should be going into alarm then dragging the others with it.

 

[480sparky]

I think they are on the loft circuit. I Can turn on every load in the house and the smokes don't go off. but if I turn on the loft all by itself, they do go off.

I'd put them on their own circuit. Find where they're getting power from and disconnect it and cap it off. Refeed a new circuit to whichever smoke is the easiest to get it to.