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motion detector security light question

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I asked this over in the home improvement forum and didn't get a definitive answer.

would it be OK to install a switch between the hot in and switched hot out on a motion detector to keep the lights on at all times? I know I can bypass the lights by turning the breaker off then back on, but that is only for one night until the built in photocell resets it in the morning.

here's a (pretty crappy) diagram of what I was thinking. would this hurt the sensor in any way?
lutful
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lutful

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I think that should be OK since it is just parallel to the photo-sensor which also acts like a switch.

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that's what I was thinking. just wanted some assurance

even if I do fry it, it is after all only a $20 part LOL.

thank you for your reply!!

leibold
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If you want to play it safe, you could use a toggle switch (SPDT):
L1 connects to black(hot) from the junction box and the black control wire from the motion detector (input).
L2 connects to the red control wire from the motion detector (output).
C (common) connects to the black wires from the 2 light.
In position 1 the lights are permanently on. In position 2 the lights are motion controlled.

If you want to get really fancy you can get a toggle switch with a center off position which allows to turn the light off completely.
lutful
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lutful

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miniature rocker switch / center off $1.32

»www.parts-express.com/pe ··· =060-674

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I actually have a few SPDT toggles at work. that sounds like a better idea---maybe I had too many beers due to the holiday weekend and didn't think it through enough LOL.

i'll be grabbing one Tuesday and hooking it up that evening. thanks for the help and ideas!!
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Tuscaloosa, AL

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said by quitaccount:

I actually have a few SPDT toggles at work. that sounds like a better idea---maybe I had too many beers due to the holiday weekend and didn't think it through enough LOL.

If this install is outside you will want to use a properly rated switch in a rain tight housing with a proper rain tight cover.

The last thing you need to do is create an electrical hazard with a wet switch.

tschmidt
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3-way switch override
said by quitaccount:

I actually have a few SPDT toggles at work. that sounds like a better idea.

Using a 3-way switch is probably overkill but can't hurt.

That is how I set up our bathroom light/fan timer using a 3-way switch to allow fan to be run continuously.

Here is a schematic if you want a pretty picture.

/tom

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said by 54067323:

said by quitaccount:

I actually have a few SPDT toggles at work. that sounds like a better idea---maybe I had too many beers due to the holiday weekend and didn't think it through enough LOL.

If this install is outside you will want to use a properly rated switch in a rain tight housing with a proper rain tight cover.

The last thing you need to do is create an electrical hazard with a wet switch.

all our stuff is for outdoor use.

the switches are 1/2" hole mount, direct exposure rated. I even have the rubber covers for them
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said by quitaccount:

the switches are 1/2" hole mount, direct exposure rated. I even have the rubber covers for them

And "listed" for that application?

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they're listed as (I believe) service disconnect switches for incandescent/fluorescent/neon signs. rated for 120-250v either 15 or 20 amp.

i'm only running 3 60 watt lightbulbs on it, so 1.5 amps. they are usually controlling 2 to 3 15000v/30ma neon transformers or a few ballasts.

...........which reminds me. if anyone needs a neon transformer for any projects, just PM me. I have a $h!tload of used ones that are still good, up to 15000v 60ma.
FTF only---they're WAY too heavy to ship.

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And just because no one's mentioned it in this thread, a "3-way" switch is just a SPDT switch.

/M

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the ones I have are only on/on. so I guess it's a 2 position in my case I have no need for an "off" position anyway. it's either on by the motion sensor, or the photocell that feeds the circuit.
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here's a diagram of how I have the switch wired. there is a photocell out to the left of what I sketched which will control the light when the bypass is activated for special occasions (Halloween, Xmas, ETC) and possibly all winter. I tested it tonight, and it seems to work perfectly with no fried sensor

thanks all for your input and help!!

tschmidt
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Great when a plan comes together.

One thing I noticed is you are switching power to the motion sensor. That's fine and saves the watt or so the sensor is using. However: the sensors I've had turn on the output for a bit when first powered up. If that behavior is acceptable great, if not leave the sensor powered all the time and switch the output for manual control.

/tom

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will the way I have it hurt the sensor at all after time? if powering the sensor all the time is better I can just jump the two wires together.

this one does power the lights for a few seconds on initial power up, but if it won't kill the sensor I may just leave it as it doesn't really bother me.

tschmidt
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The way you have is wired is fine, after all the sensor is wired in after a photocell.

I was just commenting on a potential usage issue.

/tom

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said by quitaccount:

will the way I have it hurt the sensor at all after time?

I'd be very worried about backfeeding the SSR (or whatever they're using) like that, especially with no incoming power.

This is what I'd recommend:



/M

tschmidt
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said by mackey:

I'd be very worried about backfeeding the SSR (or whatever they're using) like that, especially with no incoming power

The Triac or back to back SCRs are not being driven since the input is disconnected. The circuit as quitaccount See Profile implemented it is not going to cause a problem.

/tom

leibold
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That matches what I had recommended.

Since this particular motion sensor has a neutral connection (many don't) a current can flow through the sensor regardless whether line voltage is applied to the input or to the output (backfeed).

While I don't expect necessarily any harm to come from it, I would not backfeed the motion sensor since it is not a normal operating condition for which it would be designed.