Battery Charger Causes Smoke Detectors to Go Off
 

It took me awhile this season to figure out what was causing this. Most of the time we would get to the river the night before, take the boat out the next day, clean it, put it in the garage, and then leave.

Several times though, we would hang out at the house after putting the boat up or even stay the night and the smoke detectors would randomly go off.

We had replaced several of them before I realized that if I didn't plug in the charger for the boat (Xantrex 40A TruCharge 2), the smoke detectors would not go off. The smoke detectors are hard wired, FYI.

Anyone have any insight as to why this might be happening?

Are the smoke detectors in the garage too? I can't imagine why they would go off in the house if the charger and the boat are in the garage.

When you charge your battery's they will gas off. If your battery's charging sets your smoke detector off and your not smoking out the garage ( over charging) your charger is a high quality smart charger so i would say over charging is most likely Not the problem . I would say Mabey your smoke detector is faulty and you should change it out. They can become clogged with dust and partials that can help give you a false alarm.

No smoke detector in the garage and no CO2 sensors either. The house is only about 2yrs old and I think we've replaced all of the smokes at this point.

I'm wondering if its an issue with current draw. Once the boat has been on the charger for at least a day, the smokes don't go off.

Yesterday it happened within 10min of plugging it in. The garage door was still open too.

I text one of my AV techs and here was his response. Makes sense.

"The smokes must be picking up heat on the 110 line. Your garage breaker is probably only a 15 amp which would cause to much draw on the line and cause it to heat up. You can check that and see if it is only a 15 amp you should change it out to a 30, especially if you have other things like refrigerators or freezers."

My father in law, an engineer, text me this after I sent him my AV tech's response:

"I will have to think about. Breaker rating should only effect trip current, not circuit heating. Wire size would do that, or short/break"

According to the owners guide that model charger pulls 7.7 amps at 120 VAC. You should not be over amping a 15A circuit. Furthermore, if you are plugging the charger in the garage and the smokes in the house are going off odds are they aren't even on the same circuit which would definitely not have anything to do with the charger being plugged in.

If they do happen to be on the same circuit, since this happens within minutes of the charger being plugged in maybe the smokes see a voltage drop causing them give off false alarms. I would verify if the charger and smokes are on the same circuit. If they are then I would test to see if there is a significant voltage drop at the smokes and check the operating range of them.

You probably can't safely change out a 15 amp breaker for a 30 without running new wire anyhow.

I'm an EE and I work in the solar power space so I understand the electronics of the converter. Converting AC to high power DC can be dirty business from a power quality standpoint. That said, it is still a most unusual situation. It is possible the Xantrex is causing some distortion on the AC sine wave that is tripping up the smoke detector electronics. Did you replace your smokes with the same brand?

You might try adding a 50-100' 14awg extension cord to introduce some inductance into the power path if you have one lying around. This could be enough to buffer the distortion so the smokes don't trip. No guarantees but it's easy to try.

Alternatively you could call Schneider (parent company of Xantrex). They might be able to help you out. If you don't get anywhere with them go ahead and PM me, I can bring it up with my Schneider rep and ask him to ask one of his techs.

One more thing, make sure the neutral wire at your main service and sub-panel is good and tight.

I'm an electrical contractor and have installed or replaced 1000's of smoke detectors. I've never come across a situation like you describe. The first thing I would do to trouble shoot your problem is try plugging the charger in on a different circuit than the smoke detectors and see if the problem goes away. That would rule out any "interference" problems. Also, NEVER put a 30 amp breaker on a 15 amp circuit! That wire is only meant to handle 15 amps. You're asking for a fire if you install a breaker that is larger.

Holy smokes (pun intended),

I didn't even see the 30amp breaker suggestion. DO NOT DO THAT unless you want to risk burning the house down.

Good catch Markj.

I agree. Not good advice.

I'm going to try the extension cord suggestion and also maybe try a surge protector that does some filtering.

Unfortunately, it's not real easy to troubleshoot as this only happens after using the boat where the stereo batteries needs to be recharged.

I am no expert but could the batteries be emitting a gas during heavy recharging that the smoke alarm is picking up? This is assuming they are not sealed.....

Maybe you should reconsider what you think causes the smoke detectors to go off. It's possible you trying to solve the wrong problem.

Heck, once you begin to believe in BigFoot, then it's not a stretch to think that BigFoot's DNA can be sequenced.

http://news.yahoo.com/blogs/sideshow...190947582.html

Just turn your stereo on low before you go to work, get back home and charge away. Simple.

Just make sure you're plugged in to a different circuit than your smoke detectors.