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Posted By: Happi_Man Baseboard Heating on a Motion Sensor - 10/29/02 07:06 PM
Anyone ever heard of this. I got a guy who wants to finish his basement. He wants us to install baseboard heating and put the switch on a motion sensor so that the heat will kick on only when someone is down there. Strange but a unique idea I guess. Do they make a 220V Motion switch?
Posted By: sparky Re: Baseboard Heating on a Motion Sensor - 10/29/02 07:59 PM
i can imagine the cat figuring out how to cycle it ..... [Linked Image]
Posted By: elektrikguy Re: Baseboard Heating on a Motion Sensor - 10/29/02 08:02 PM
intersting concept. Doesn't sound that easy to me. Assuming you can find a 220v motion detector rated for the application. He would have to make periodic trips to the beer fridge to keep the heat going. hmmm. maybe not a bad idea when I think about it.
Posted By: Trainwire Re: Baseboard Heating on a Motion Sensor - 10/29/02 08:28 PM
Piece of cake.

My local hardware store sells "stand alone" motion sensors, you wire them into your existing light. Stick one of those up in the corner of the room opposite the door, and wire it to a 120v coil of a contactor rated for the heaters. If you feed the heaters with 3 wire, then you can snitch the 120 off of one of the heater feeds. ( using the right size wire of course.) materials: motion sensor, contactor, box to hold it all, hand full of wire.
TW
Oh yea, the sensor will have to have its "dusk to dawn" feature disabled, but most have a setting or a "test" feature that will do that.

[This message has been edited by Trainwire (edited 10-29-2002).]
Posted By: JBD Re: Baseboard Heating on a Motion Sensor - 10/29/02 08:28 PM
Why not use a standard 120V motion sensor and have it feed a power relay. I like the Relay In a Box (RIB) devices from Functional Devices. http://www.functionaldevices.com/ChartPowerEnclosed.html
What about a thermostat with a setback. They make many types. One has a photcell. When it is light the heat is on at the full setting. When the light is gone it goes to the setback temp.
Posted By: jlhmaint Re: Baseboard Heating on a Motion Sensor - 10/30/02 02:41 AM
hasn't he ever heard of the theory that is more efficient and cost effective to keep the room at a constant temp rather than trying to heat it up when you need it.
Posted By: sparky66wv Re: Baseboard Heating on a Motion Sensor - 10/30/02 05:05 AM
Valid point, Jerry.

Had a call last year about this time from a medical billing company. They want(ed) to be able to have a "little" space heater in each one of the cubicles.

After trying in vain to explain to them the scope of what they were asking, I asked why they couldn't just turn the thermostat up a few notches?

No, they'd rather run 24 1500W heaters all winter long...

Lessee: 1500W x 24 units x 12 hours per day x 20 days per month / 1000 to convert to KWh x $0.08 per KWh...

Uh, (*tapity-tapity-click-click*)that's uh, $691.20 per month in Power not counting the sub-panel, receptacles, and all the other work involved... (If I got the math right...)

Sheesh!

</threadjack>

Oops! I Did it again!! [Linked Image]

</channelling Britney Spears>
I would also incorpoarate a timed relay into the control circuit in conjunction with the motion sensor. That way When person enters the room heater comes on. Lets say man becomes immobile and motion sensor goes off. Timed relay would keep heater on for a preset length of time (10 min. for example) after man becomes immobile. This would avoid heater short cycling. and man stays warm. If man would come back to life before preset relay's time is up, motion sensor would kick in again, thus resetting the system and avoid interruption in heat.
Posted By: go-go Re: Baseboard Heating on a Motion Sensor - 10/31/02 01:45 AM
[Linked Image] I think it might take just a little longer than 10 min. to heat a room.

[This message has been edited by go-go (edited 10-30-2002).]
Why would you want to heat the room in ten minutes? The timed relay has nothing to do with the time it takes to heat the room. It merely is there to keep the heater on during periods of time the motion sensor does not sense movement. Most motion sensors have a delay built into them however this relay would allow even more of an off delay.
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