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James Mendicino
Electrical/ house alarm conflict

When we built our house 6 yrs ago, we had our electrician install a whole house alarm. This included a motion detector and alarm with the opening of any door or window. We also had rotary control switches installed for every ceiling fan. When several of the switches are turned (always the same three & only sometimes), the alarm sounds - as if a door or window just opened. All alarms are hard wired throughout the house.
Do you think the alarm wires are routed too close to the three swiches causing a pulse in the alarm system? If the switches are the problem, are there rotary switches available that are electrically isolated to prevent emitting extraneous signals? Or is the replacement of the rotary swiches with toggle switches the only solution?

Jim Mendicino
Waterloo, SC

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James Mendicino
Re: Electical/house alarm conflict

There is only one motion sensor and it is in view of only one of the fans. The fans are all in the same general area, within approx 30 ft of the sensor, but two are in other rooms. The system is armed when the problem occurs. No problem when not armed.
Multi-wired circuits? If you mean - are the fans controlled by several switches? - the answer is no.

Fan wiring: 2 sets of wires - one for light and the other for fan control. The rotary switch for fan control is stepped - high/med/low speeds.
Not sure but I do not think the fans are remote control capable. I can't check fan literature as I'm on the road.
Thanks for responding. JimM.

Re: Electrical/ house alarm conflict

It doesn't sound likely it's the electrical for the fans that is activating the motion detector setting off the alarm.

It's not mentioned where the main panel for the alarm is ... on the main level or in a basement. If it's located in a basement then likely the alarm wires were ran straight down from the contact points ( including the motion detector ) to the basement not coming close to the fan controls. If it's located on the main level it's likely the motion detector wiring is run from above to the panel.

This might work as a test while you're at home .... cover the motion detector then arm the system and turn on the fans to see if the alarm goes off.

Chances are the fans may be moving something like a plant or window coverings that are in view of the motion detector. You mentioned there is one fan directly in view of the detector and depending on the focal point this fan may be the culprit. Another point is if it's an infrared ( heat ) detector they work on a change in infrared so the fans can be causing this .

Good luck.

James Mendicino
Re: Electrical/ house alarm conflict

The main panel is located in the garage on the opposite side of the house (basically the same level) - so wires are most likely run overhead. There is a sub-panel in the basement for the gameroom, bath, hot water tank & work shop.
The alarm sounds at the instant the rotary switch is turned, so plant movement can't be the problem. And that cause wouldn't explain the alarm sounding with the other two fans in different rooms.
The electrician states he has installed this particular system in other houses & has not had a problem. It might be a good idea at this point to contact the alarm manufacturer to see if they can offer any suggestions.
Thank for your input.

Re: Electrical/ house alarm conflict

It's difficult at times over the internet to have all the details of how things are installed and situated. For example where the fan control switches are located in relation to where the keypad , motion detector , other contacts are. Also are they located on the same wall or on the back side of the same wall , etc.?

Another suggestion would be to do the process of elimination like disconnecting the motion detector from the panel ;arming the system then turning on the fans and so on.

You're right if all else fails contact the alarm manufacturer for input.

Re: Electrical/ house alarm conflict

now in the market are better alarm systems that you can buy, your system seems like a little older, why don't you try a new one, ? are not expensive.

Re: Electrical/ house alarm conflict

Possibly electrical " noise " generated by the rotary switch . Maybe try replacing one of the offending switches with a different brand .

I assume the alarm system has a battery back up ? You might try killing the AC feed to the system and while it is running on battery , operate the fan switches . Isolate individual alarm contacts or sensors and repeat if nescessary .

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