Office Lighting

[DukeHenry]

Good morning, all.

My office is attempting to install occupancy sensors in many locations as part of an energy conservation project. Apparently the lighting in the office was wired without any ground wires (the building is close to 60 years old.)

I've been told that any major renovations would require us to correct that, but I wouldn't consider this to be major. Is there anywhere that defines what a major renovation would be?

Thank you in advance for any assistance.

Have a good day!

 

[TNBaer]

If you attempt to install wall mounted sensors without grounding they will not work. Odds are the sensors will never turn off. I've run into this problem many, many times.

So while you may not have to upgrade the system per code, you certainly will have to with wall mounted sensors. The other option is to go with low voltage ceiling sensors which will certainly cost more.

 

[TNBaer]

One more thing, if the box is grounded but it lacks a wire, Sensor Switch sensors are the way to go. They do not need a ground wire so long as the box is grounded.

http://sensorswitch.com/

 

[DukeHenry]

One more thing, if the box is grounded but it lacks a wire, Sensor Switch sensors are the way to go. They do not need a ground wire so long as the box is grounded.

http://sensorswitch.com/

I believe this is the case, but I haven't had a chance to look into any of the boxes yet. They handed me several boxes of these Enerlites switches they bought months ago. I'll probably give it a shot to see if it works. If not, those Sensor Switch units might be the way to go.

Thanks for the help! It is very much appreciated. Have a good one.

 

[texie]

If you attempt to install wall mounted sensors without grounding they will not work. Odds are the sensors will never turn off. I've run into this problem many, many times.

So while you may not have to upgrade the system per code, you certainly will have to with wall mounted sensors. The other option is to go with low voltage ceiling sensors which will certainly cost more.

I would agree that with some sensors the lack of grounding will be a problem. Depends on the sensor brand/model. With any luck the OP has a neutral at each switch, then he can use a "neutral required" sensor and have better reliability. Like you, I like the SensorSwitch brand as they have a model for most every situation and I have found them to be reliable.

 

[Electric-Light]

The two wire type switches that use relay and work with CFLs use ground bleed to power itself.
Such example is the consumer model Wattstopper they sell at the Home Depot. Even with the relay closed, the small bleeding current from hot to ground allow the electronics to function. These were developed for residential use in mind to accommodate CFLs where neutral is not available in the box.

If neutral is available at the box, go with three wire type switch. (load, line and neutral).

One more thing, if the box is grounded but it lacks a wire, Sensor Switch sensors are the way to go. They do not need a ground wire so long as the box is grounded.

http://sensorswitch.com/

Or, you could simply bond the ground wire to the grounded box.

 

[iwire]

Apparently the lighting in the office was wired without any ground wires (the building is close to 60 years old.)

Is the building wired with conduit?

 

[DukeHenry]

Is the building wired with conduit?

In some locations. It's actually a combination of areas that were built at different times. There's probably not going to be one type of switch that will work everywhere.

 

[steve66]

I've been told that any major renovations would require us to correct that, but I wouldn't consider this to be major. Is there anywhere that defines what a major renovation would be?

Thank you in advance for any assistance.

Have a good day!

The definition of a "major rennovation" would be up to the local code enforcement officials.

But typically, I wouldn't think installing sensors would be a major rennovation.

Ditto on what others said: you can buy sensors that need a ground, and sensors that don't need a ground.

I think Iwire is suggesting the metal conduit could be the ground.

 

[TNBaer]

Or, you could simply bond the ground wire to the grounded box.

You could, or you could simply not do that by choosing a product that doesn't necessitate a ground wire.

Whatever.

We had a pretty large church in the area recently ask us to install 50 some odd sensors in every room, closet, etc. At first, I tried to buy some Intermatic sensors, they were a little cheaper. But, again, all the wires were specific. I had a couple Sensor Switches here in the office, the electricians looked at me and said they didn't want to deal with the Intermatic or Watt Stopper because they were simply more difficult to install. So I sent it all back and got SS instead. I order Sensor Switch exclusively now. I have no partiality to any other lighting product besides for sensors. I beat their drum, it's a good product, it saves me time, there's not another sensor on the market that installs so painlessly.