Occupancy Sensors

sckeeth

Do you guys have a particular brand that you like to use. I have a house that needs these in almost every room to get around having flourescents, instead of incandescent.

mickeyco

Leviton makes them, never used them so I don't know how good they are. Where are you at thet they requiring fluorescents in all the rooms? Can you have both fluorescents (main) and incandesants (secondary), or fluorescents only, if both why not do the old temp fluorescents until after the inspection.

http://www.smarthome.com/2522W.html

robertc65

We have these all over the place in the building where I work. Some offices have their own sensor just for that room. It seems that if the person in the room is very still for to long the lights will go out. I'm the poster child for ADD so I don't have an issue. They just wave their arms to flick the light back on. In some cases relocating the sensors works but it's not 100%. I'd like to know if their is a 100% solution.

Rob

MSSI

I installed a few in a Drug/Alcohol Rehab awhile back and had to replace them with toggles 2 weeks later....Seem these guys were still a little foggy and kept poking the lens out trying to turn the light off..

mdshunk

A word of caution....

Occupancy sensors normally require a minimum amount of connected load in order to switch properly. When switching fluorescents in a commercial application, this isn't an issue. When you're switching fluorescents in a residential application, the fluorescent lighting load is often not enough to make the occupancy sensors switch reliably. The fixture can flickler, partially illuminate, or not illuminate at all. Check the specs of whatever occupancy sensor you're looking at to see if the minimum permissible load will jive with your proposed connected load. Occupancy sensors mounted overhead generally function much better than occupancy sensors mounted at the typical wall switch location.

Hope that helps.

Sparky Joe

Didn't know that MD.

So the load current needs to be greater than the 'break-over' current of the electronics in the device. Good Stuff

mdshunk

I learned that the hard way. It was a hallway, with a 2 lamp incandescent fixture. Worked fine with two 60's, but when we put in the two 13 watt fluorescents, it carried on. Looked at the literature, and the occupancy sensor needed at least 100 watts (approx, from the top of my head) to trip it on the right way. Since then, I've looked at the literature for other occupancy sensors, and they all seem to have a minimum load listed. I'm sure there are some out there that won't be so troubled. I've just not run across any of them yet. Occupancy sensors are mostly reserved for commercial occupancies anyhow, so they'll normally have plenty of load on them. It would be a non-issue in that case.

sckeeth

[Where are you at thet they requiring fluorescents in all the rooms? Can you have both fluorescents (main) and incandesants (secondary), or fluorescents only, if both why not do the old temp fluorescents until after the inspection.

http://www.smarthome.com/2522W.html[/QUOTE]

I live in california if that tells you anything. They have to be pin based sockets so switching them out is not really an option. The occupancy sensors have to be manual on and then a predetermined time with no movement and then it turns off, it is not the type of sensor that picks up movement to turn on if that is any clearer. So with that said any suggestions.

robertc65

As far as these needing to have a minimum load, this applied to any sort of switch that uses a TRIAC internally to swith the load. Lots of dimmers are the same way. One way to avoid this issue all together is to find an occupancy sensor that uses a relay instead of a Triac. With a relay the load could be 1 watt and it would still work.

My 2cents (which is about all it's worth)

Rob

Rugger

Is an automation system/security system a possibility? Ceiling mount motions in each room with outputs from panel operating light circuuits. Could also do much more than just lights. Just my over priced 2cw.

Rugger

Sparky Joe

That's good stuff Robert. I appreciate getting my memeory turning again. Meaning my teacher has drawn the schematic of how a solid state dimmer works in the past.
I can see the picture in my head, but can't remember how it works, could you draw a simple picture Rob?

Thanks, -Joe

MSSI

So would an occupancy sensor work in series with a dimmer? and would the occ. sensor act differently if wired before or after the dimmer?? Throwing this one out there before I really put any thought into it. sorry, its late.

Sparky Joe

It sounds like it should work, though I would put the occ sensor before the dimmer because it's simply an on/off device, whereas the dimmer is changing the RMS power to the circuit.

MSSI

Yeah after a second of thought..the occ. sensor wont work if you have the power to it reduced or off..Duh... Wiring the dimmer on the other end, I assume will work if you are applying enough load to the occ. sensor.

mdshunk

If you do that install, post how the dimmer worked out wired after the occupancy sensor. I'm curious to know if it works. I know that you can't do CF's on an occupancy sensor normally, so I wonder about a dimmer. I know you can do the PL lamps on an occupancy sensor, though. Not sure what the difference is in the ballast technology built into a CF and the ballast that is bolted on the PL fixture. That's what causes me to think that a dimmer might be a crapshoot.

MSSI

well I have the opportunity to try this over the next 2 weeks I will get back to ya on it to let you know..But a followup question on this,, By code if you use an occ. sensor in a closet with incadescents does that give you the leway to not totally encolse them???i/e non shower light??

mdshunk

No exception like that in the NEC, but maybe a local amendment someplace. I sorta doubt it, though.

Sparky Joe

so what's a CF and what's a PL?

You guys and your abbreviations are killing me.

mdshunk

Sorry about that. I thought they were in common use, but maybe they are regional terms.

CF=Compact Fluorescent


PL = I have no idea what PL stands for, but these are PL lamps:

mdshunk

Ahh... PL = Phillips Laboratory.

They aparently invented the PL style lamp about 1979