Controlling a light switch, no neutral

M

MikeB

Active Member
Anyone have a recommendation on controlling a light switch with no neutral? I'm looking to control a switch from a different room in a commercial condo (2 phase). Was going to use INSTEON, but there is no neutral at the switch location and I don't want to go to the fixture.

Looking for something quick and easy. Any recommendations? Doesn't necessarily have to be controlled by another wall switch, though that could work. Could be some sort of RF remote control as well.

Thanks in advance for any suggestions!
 
Sorry, forgot to mention - needs to be a relay (controlling fluorescent). Those Z-Wave on/off switches look like a possibility. Is there a scene controller that does not require a neutral that I could mount in the other room, or would an RF remote be the way to go?
 
Lutron_Switch.jpg

That brochure I linked above, to Lutron Maestro RF, shows this switch - and the brochure states that a non-neutral version is available.

Edit - If you want to use Lutron Maestro RF, try to figure out which 2 switches (or switch plus Pico controller) you want, and then call a local electric supply house. Speak to the lighting guy, to make sure what you've chosen will work. I wouldn't trust the HD/Lowes guys to know much about these switches. Use the knowledge of the electrical distributor salesman, free and reliable advice.

The professional custom installers benefit tremendously from the distributors, when spec'ing new products. It's resource that DIYers don't have great access to - use it when it's available (AutomatedOutlet.com comes to mind here, for non-Lutron stuff).

Edit - if you go with Z-wave, you'll pay for delivery, and wait for it. And return will be difficult. And you may not find a distributor/vendor as knowledgable as the local electric supply store lighting guy.
 
MikeB said:
Sorry, forgot to mention - needs to be a relay (controlling fluorescent). Those Z-Wave on/off switches look like a possibility. Is there a scene controller that does not require a neutral that I could mount in the other room, or would an RF remote be the way to go?
Click to expand...

The Zwave on/off switches that are listed are for Incandescent lamps only. Two wire switches use the load to complete the circuit from hot to neutral for communications. Most of these switches specify a minimum wattage for the lamp (40 W is typical) to ensure they can establish a reference to neutral.

My information is far from current (I'm not up to date on the Lutron line), but I do not know of a 2 wire switch that can control a fluorescent. I'd be happy to have someone correct me. I have locations that could use this as well.

IM
 
IndyMike said:
MikeB said:
Sorry, forgot to mention - needs to be a relay (controlling fluorescent). Those Z-Wave on/off switches look like a possibility. Is there a scene controller that does not require a neutral that I could mount in the other room, or would an RF remote be the way to go?
Click to expand...

The Zwave on/off switches that are listed are for Incandescent lamps only. Two wire switches use the load to complete the circuit from hot to neutral for communications. Most of these switches specify a minimum wattage for the lamp (40 W is typical) to ensure they can establish a reference to neutral.

My information is far from current (I'm not up to date on the Lutron line), but I do not know of a 2 wire switch that can control a fluorescent. I'd be happy to have someone correct me. I have locations that could use this as well.

IM
Click to expand...

I believe your right Mike. A two wire switch/dimmer has to pass trickle current through the fixture to establish a complete circuit for self power. It definately leads to some undesired effects with flourescent lights.
 
OK, let me go a bit further then! It's a single switch controlling a high wattage halogen bulb (300-400w I believe) + 4 32w or so fluorescent bulbs. Does this change anything?
 
MikeB said:
OK, let me go a bit further then! It's a single switch controlling a high wattage halogen bulb (300-400w I believe) + 4 32w or so fluorescent bulbs. Does this change anything?
Click to expand...
Yes it means you really need to run a neutral, or use a fixture mounted switch where the neutral is available. Any two wire switch will be dimmable and most flourescent fixtures do not like dimmer switches, and most dimmer switches don't like flourescent fixtures with magnetic or electronic ballasts.
$0.02
 
dave w said:
MikeB said:
OK, let me go a bit further then! It's a single switch controlling a high wattage halogen bulb (300-400w I believe) + 4 32w or so fluorescent bulbs. Does this change anything?
Click to expand...
Yes it means you really need to run a neutral, or use a fixture mounted switch where the neutral is available. Any two wire switch will be dimmable and most flourescent fixtures do not like dimmer switches, and most dimmer switches don't like flourescent fixtures with magnetic or electronic ballasts.
$0.02
Click to expand...
Back pedaling a bit. I do run three CFLs and one incandescent with a standard two wire X10 dimmer wall switch. The incandescent bulb supplies the required path to neutral for the switch electronics. If the incandescent burns out nothing smokes or overheats since the switch no longer sees a path to neutral. This would not be true if the flourescents were magnetic ballast. I think smoke might be released from something.
 
Hello Mike,
Just to confuse the issue a bit more...

http://store.homeseer.com/store/HomeSeer-Z...trix-W7C37.aspx

I was trying to figure out how the Leviton and Cooper switches could use a relay output with only a two wire connection (no neutral). The answer is, they can't.
The 2 wire Leviton VRS05 (5 Amp) and Cooper ZRW103 (8 Amp) On/Off Switches are actually dimmers (triac output) with the dimming function disabled. If you look at the install sheet, they specify de-rating for multi-gang installations. There's no reason I can think of to de-rate a relay output switch.

The other switches appear to be true relay units, use 3 wire connections, and can control inductive and capacitive loads.

As Dave_W indicated, your halogen lamp can provide an adequate load path for the 2-wire switch to generate a reference. The real question is one of failure modes. If your halogen were to die (or be replaced) the switch (triac output) and or fluorescent could well become unhappy. This normally results in the release of the "magic blue smoke".

What type of fluorescent are you using (CFL, magnetic ballast tube)? Could you switch to dimmable CFL's.
 
They are tubes, and I'd rather not switch them out... though I guess I could if I need to. Problems is these fixtures are about 20' up, so I'd prefer to leave them be!
 
I know you said you don't want to go to the fixture, but if you have access to it, it may not be all that bad. Depending on budget and desired reliability, you can always go to the power source and wire a relay module at the fixture, and rewire the switch so that instead of power and return, it's hot and neutral, with no return - meaning it'll only power a switch with no load. It sounds bad, but I did this in a couple of locations, and it really was my best option to get full automation and compatibility.
 
MikeB said:
They are tubes, and I'd rather not switch them out... though I guess I could if I need to. Problems is these fixtures are about 20' up, so I'd prefer to leave them be!
Click to expand...

Sorry Mike, that was a dumb question - I missed where you stated you had 4 - 32W fluorescents. That being the case, your ballasts a very likely magnetic fast start units. I can't recommend any two wire switch for that configuration even with the halogen in parallel. If the halogen dies, bad things could happen. Sorry to bring up the failure mode stuff again. Unfortunately I did a 2 year stint in reliability during the Carter administration (or was it Ford). Anyway, it ruined me for life...

If it helps at all, I have a similar situation in my garage. Six 4 tube T40 fixtures 14 feet up - no neutral in the box. Actually, there is a neutral in the box, but it's from another circuit (opposite phase). That darn reliability stuff still haunts me. I can't make myself use the "wrong" neutral.

I'm going to have to side with Dave_W and Todd on this one. Installing a relay unit at the fixture appears to be the "proper" solution.
 
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