Low Voltage Wiring questions & answers:

Diagnostic questions help repair low voltage wiring systems in buildings.

This article series provides a diagnosis and repair guide for low voltage electrical wiring typically used to control 120V home lighting, electrical receptacles, and other devices.

We discuss low voltage electrical wiring inspection, diagnosis, repair, parts replacement, finding low voltage relays, replacing low voltage relays, finding low voltage wiring diagrams, and low voltage electrical wiring parts from GE®, Remcon, Sweepe, Bryant, Sierra, Touch-Plate®, general use low voltage relays, and where to find home electrical system low voltage wiring diagrams helpful for performing low voltage wiring repairs.

The photo at left shows a GE low-voltage relay box in a residential attic. Photo courtesy of True Tech Electric.

Low voltage electrical wiring (GE, Remcon, or Other Low-Voltage Building Electrical Wiring & Switches) was installed in some homes beginning in about 1946's. This system was popular and was installed in many homes between 1960 a nd 1985, and it continues in use today.

These questions & answers about building electrical systems, wiring, & components were posted originally

at LOW VOLTAGE WIRING REPAIR or UPGRADE be sure to see the suggestions at that page.

Troubleshoot Bryant low voltage rocker switch

On a Bryant lv rocker switch I' m getting 24 v on the black and red wire checking it to the common on the switch whether I toggle it to the on or off position.

Shouldn't one side go to 0 volts when I toggle?

Also the relay to turn light on does not engage to close contact on relay. Can you help me out on this one? - 2019-06-07 by Chuck -

Reply by (mod) - bad low voltage wiring rocker switch for light

I'd like to help but I'm confused by the question. Perhaps you could make a drawing or show me a photo of the wiring.

It sounds as if there's a bad rocker switch - yes most low-voltage light switches are on-off. Remember to also check the relay itself.

Did some 1950's Remcon low voltage light switches glow in the dark?

My son recently bought a house built in 1957 that has the Remcon low-voltage switch system, and we were noticing the other day that the rocker switches actually will glow in the dark after being exposed to light for a while, but I believe the glow effect tends to fade rather quickly.

Is this how the switches were originally made? - On 2018-03-29 by Scott

Reply by (mod) - Yes

Scott:

Yes there were several brands of light switches, including from Remcon, that absorb energy and glow in darkness or dim light. Kyle Swtichplates is among suppliers selling replacement parts for low-voltage lighting systems including replacement parts for old Remcon switches.

Here is what Kyle says:

Old style ovoid Remcon switchplates were typically installed horizontally with switches rocking up and down vertically to turn lights on and off. The wall plates were clear plastic with a gold backing paper. The slightly flared switches were pinched in and narrower at the middle, then wider at the top with a small centered dot.

These hourglass-shaped switches were a bone color and were impregnated with a non-harmful phosphorescent material so that they glowed in the dark for about an hour after the lights were turned off before eventually fading.

Note that the original type of Remcon mounting straps, ivory curvy rocker switches and rounded or oval wall plates are no longer in production and were eventually replaced with newer line of black Remcon snap-in switches and stainless steel cover plates (discontinued in 2011). - source: Kyle Switch Plates, retrieved 2018/09/12, original

source https://www.kyleswitchplates.com/remcon-low-voltage-lighting/ - Tel: 800-551-5953

How to determine if the problem is the low voltage on-off type switch or the light or the wiring

I have low voltage system in my house. Some area of the house have one rocker switch, other plates have 2, 4,even 6. My bedroom has 9 switches.

I ordered a 2 switch plate for every single rocker. I believe I need to order a 4 for every plate with two switches?

Am I right about this? I just confused how to wire these.

Also, I am not sure if a switch is broke because some lights dont even work even when I install a new bulb and twist it on. Could this be a relay? I can't even find these relays in my house. On 2017-01-11 by Brian

Reply by (mod) -

Brian:

One way to determine if the problem is a low voltage toggle-type "on-off" switch is to jump the two switch wires together - that's the same as turning the switch "on" - if the switched circuit or light stays off the problem is probably the relay control or a wiring defect, assuming you know the bulb and fixture are good.

I'm not sure just what type of switches you have installed. If you have a type of "rocker switch" that does not flip to a solidly on-or off position, that is, if it's a type of "press to operate" switch, then I wouldn't jump its wires together as that might burn up a relay or low voltage transformer.

If you can identify the type of switch, brand, model, labeling, or send along photos (page top or bottom CONTACT link) that might let us comment further.

Why do my lights stay on even when I turn off the switch - and the transverter box is burning hot!

I have replaced my transverter box because all of my lights that were on, stayed on and the ones that were off stayed off. The tranverter box would burn you to touch it. everthing is still the same. What could be my problem? On 2016-06-04 by Anonymous -

Reply by (mod) - short circuit fire and shock warning

Watch out: you probably have a short circuit somewhere in the system - risking both fire and electric shock.

Turn off power.

Trace the wires.

Look for a wiring error that connected 120VAC to the low voltage side of a circuit.

Why do only two of six lights on my low voltage circuit turn on?

I have 6 lights on a low voltage circuit. Occasionally only 2 will turn on. Is this a transverter problem or something else? - On 2016-03-09 by Rod Johnson. rjohnson@gprnm.com

Reply by (mod) -

If the same transverter is powering all 6 lights then more likely the problem is failing bulbs or bad wiring.

How to fix low voltage bathroom lights that won't turn on

How do I trouble shoot low voltage to the lights in bathroom , bed room and bathroom. They don’t work - On 2018-08-20 byCoy R Nichols

Reply - by (mod) -

Coy

In essence, follow the wires.

If the problem is a switch then jumping the switch wires will turn the lights on.

If the problem is a relay, swapping one from lights that work can confirm that was the issue.

Watch out: if you're not familiar and trained in electrical work you could be shocked or killed, especially at the line voltage connections and wires.

Some but not all Landscaping lighting won't turn on

I have installing a all new landscaping lighting.
it is a 300W transformer with 2 ways.

my 1st run wire is connect with 6 supply lights: (2 of them don't work) I tried to switch them but these spots never work

my 2nd run wire is connect with 4 supply lights: (2 of them don't work neither) I tried to switch them but these spots never work

do you have any idea ?
thanks On 2018-02-08 by Richie

On 2018-02-09 by (mod) - when some lights work and some don't

Richie

If some of the lights work and others not on a circuit I would be looking for

- a bad wire connection

- a bad bulb

- a bad local transformer

- a bad switch

Why won't a low voltage light turn off and the wire is hot?

We have a low voltage system and one of the lights stay on and the wire hooked to the output of the relay is live with 120 volts the relay switches the 120 volts when the wire is disconnected. why could the wire be hot On 2017-12-04 by Anonymous -

Reply by (mod) -

I'm not sure that I understand the question correctly, but it sounds to me as if the low voltage relay switch has failed or you've mis-wired the light.

Remco low voltage security light won't work after new electric meteer installed

I have always had a motion activated security light on my Remco low voltage system. Never a problem. I never turn the switch off. The switch is always on and the light worked properly dusk to dawn.

Recently the power company pulled my meter and put in a 'smart meter' and immediately the light randomly started coming on, then off, on, off..all night long. Replaced the fixture and problem continues.

Could the meter swap have damaged the transformer relay? Should I even be able to use this type of light with the relay? Any ideas? On 2017-11-16 by Bob

Reply by (mod) -

I'd be surprised if only changing the electric meter would cause the Remoco system to fail, though a power surge could have damaged a relay.

Check or replace the Remco relay.

 

What causes a voltage drop when a light is switched on?

What Exactly Is That Can Cause A Low Voltage In Building When The Light Is Switched On - On 2017-08-23 by Abdulraheem Taofeek -

Reply by (mod) - variation in supply voltage level

Abdul

Start with your power company: depending on where you live voltages can vary considerably.

Next high loads on a circuit such as equipment switching on can dim lights.

Watch out: Dangerous: dimming can also be caused by electrical short circuits for example to earth - that justifies investigating the wiring system to be sure there are no dangerous situations as someone could be killed. I've seen this when someone put up a metal fencepost that cut into the buried electrical cable.

All my low voltage light switches stopped working - do I need a transverter?

all switches stopped working. none of them are stuck...the usual problem. do i need a new transverter?
thanks! On 2015-10-29 by joe

Reply by (mod)

Joe:
Check the voltage at the switch control boxes or at at least one you can access.

If the switches aren't getting power out of the transverter but power is being delivered to that device, then yes, I'd replace it.

Grasslin low voltage power control reset button? Landscape llights won't turn on

does the grasslin 30600-172 low voltage power control have a reset button? There are 2 switches on the control panel but I dont know what their function is.

My landscape lights do not come on at all, but there is power to the power outlet, the timer appears to work, & I have checked the bulbs. - On 2014-07-13 by deb

Reply by (mod) - contact information for Grasslin - TFC Group LLP in Kent, UK

Deb,

Grasslin Controls is a UK company, part of the TFC Group, who can be contacted directly so that we get this right. See

http://www.grasslin-controls.co.uk/
TFC Group LLP
Tower House
Vale Rise
Tonbridge
Kent
TN9 1TB UK

Tel: 01732 351 680
Fax: 01732 354 445

Since I didn't see your LV power control listed, I'd give them a call or an email.

Daniel

Where to find low voltage relays for a GE control system in an old Church

Having issues locating the relays in a church, one of the switches is near a breaker panel but (assuming) the relays would be in it's own panel what other areas should I look for them at? I've checked about every closet, I have a bank of lights that wont turn on and it's the GE control switches with the On and Off dials. On 2014-04-02 by Michael -

I recently took over as Grounds Keeper for a local church. They have the LV GE system in the main sanctuary. We have had trouble lately with one of the overhead lights. I have found the relay box tucked away in a furnace room. The switch controls 8 different lighting locations and they all work perfect except for one.

After reading this article and all the post I am assuming its a bad relay. I have not heard mention or even seen a switch like they have though. Its a round dial numbered 1-9 with a on/off toggle pad at the bottom. On the back is a round (potentiometer) looking housing with 10 red 10 black wires and terminals.

Wish we could show pictures here. Thanks for the article and the help. I will get back to troubleshooting the relay Monday. Will let everyone know here so maybe to help someone else.

Reply by (mod)

Typically the relays are in a box in a ceiling, crawl area, adjacent garage, etc. not necessarily right at the panel. On occasion low voltage relays are also in the electrical box right next to the switch or fixture.

Where to find Remcon system low voltage relays in a building

Where would you usually find the low voltage relays? , I have an old Remcon system On 2014-03-11 by Anonymous -

Reply by (mod) -

Anon

Good question.
Because they need to be accessible for service the low voltage relays are not usually buried in walls or ceilings (which would also violate the NEC).

Look in:

- the attic floor
- the basement ceiling
- unfinished walls of a garage or utility room

Let me know if you find them somewhere else as that may assist other readers.

On 2012-11-23 by (mod) -

Doug, I read your comment and speculation but didn't see a specific problem nor question.

The original concept was to save on more costly heavier copper wire by using it only where necessary to conduct current to the end using device. That approach can also be safer in some respects. The system was nor a gimmick in my view, but I agree that compared with systems that don't have to include a bunch of relays, LV is more complex and at old age more trouble. So the money saved on copper at installation may have been repaid in parts and labor by now.

Troubleshooting a Touchplate low voltage system - lights won't come on or off

I have issue with touchplate system. 3 of the touch plates in house intermittently turn lights on. hit the button you hear the relay and light flickers but will not stay on. Other lights in house work fine. I thought issue was with touch plate switches,so I pulled of touchplate and touch bare wired together, and same thing happens,hear click and no light.

DO you think its possible the transverter/power supply is going out. I went up in attic and disconnected the wire that went to the switches, and nothing in house will work,so I assume that is the only power supply for house. I have also read that maybe a relay is going out,but then I thought how could 3 go out at same time. thanks for advice. mark

I went ahead and replaced transverter, and now non of the lights work, I was able to get one light to come on,but would not turn off, Help!! thanks On 2012-08-16 by mark -

Reply by Jeff

MARK
if I were you, I would buy a volt meter that reads DC voltage as well as AC. Make sure your new trabsverter is outputting 28-30 volts DC. It IS possible to have bad new parts.

Found low voltage relay box in the attic: replacing with type RR5

Thanks, gentlemen. Here's the latest. I crawled back up in the attice and disconnected each relay one by one while my wife turned the wall switch on and off. Crude and not at all effective. No luck. Them light mad fan come on early in the morning and late at night, but not during the heat of the day.

The problem seems to be heat related. I understand these relays are heat and cold sensitive, so that is likely the problem.

Why the box was mounted in the unfinished attic is beyond me. A real pain. I located a local electrician who is coming next week to look at it. I suspect at least one relay will need to be replaced. I don't know the yep off hand, but suspect they are the RR5 type. Is there a suitable replacement for the RR5? Again, many thanks. On 2012-06-01 by Cliff -

Reply by (mod) -

Good progress, Cliff. I think the low voltage relay panel was often located in an attic or garage as a compromise among these rules:

- codes prohibit burying electrical boxes and panels hidden behind walls or ceililngs - they have to be accessible

- on one wanted to look at that rats nest of complexity as it was often sloppily installed, sometimes by an amateur

- while it would be more convenient to locate the collection of low voltage relays in a garage or baswsement -more accessible, that is, the wire lengths would be increased

Check with the suppliers we listed above when you determine that you need to replace an RR5 relay.

 

Why would low voltage lighting come on without anyone touching the switch?

What might cause low voltage controled lighting in a home to come on without the switch being activated? On 2012-05-22 by Stan Sarnacki

Reply by (mod) - some things to check

Stan, just a few guesses:

- a failed relay

- a bad light switch

- loose wires anywhere in the low voltage system

- a bulb with a failing filament, with the circuit in the "ON" position may flicker between on and off

Followup by Stan

Thanks for the response to my question. There is current coming into the wall switch, which I replaced. The fan and light now work intermittently. I crawled into the attic and looked at the relay box and transformer. Could see nothing amiss.

My best guess now is it's a bad relay, working at times, not working at others. The relays are not marked as to which serves what switch. Is there a way to locate the problem relay? Thanks, again!

Reply by (mod) -

Stan / Anon:

It sounds like a bad relay - a part that does indeed fail. It's also common that you find a rats nest of messy, un-labeled wiring.

You may be able to find the right relay and wires using a wire tracer device sold for circuit identification, or by using a VOM.

When you think you have the right relay, and on the theory that you're lucky enough that just that one is bad, try temporarily swapping in one of the other relays to see if that fixes the trouble.

Low voltage switch stopped turning on fan and light

We have a home built in 1964 with the GE low voltage system. The fixture in our den has a ceiling fan with light kit.

A couple of days ago, I touched the rocker switch and found neither the fan nor the light would come on. We replaced the light kit and checked all visible wiring coming from the ceiling and into the light kit. No problems were seen.

I tried two more switches with no success. It appears there is no voltage getting to the switch.

The main box for the system is in the attic, but it seems like if the problem was there, more than one switch would be affected. Everything else on the same circuit works fine.

Any suggestion and ideas as to what the problem is and how it cab be fixed would be greatly appreciated. Thanks! On 2012-05-19 by Cliff -

Reply by (mod)

Cliff:

I'd check in the main box you described, for a loose wire or a bad relay. Also check the rocker switch itself with a VOM to see that it is working

 

Thank you to our readers for their generous comments

On 2011-07-30 by Jim

Father-in-law built house in 50's w this type of system some relays are now bad info here sounds good & a place to possibly find parts thanks

...

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