I just purchased a home that was built in 1957 and all of the lighting fixtures are controlled with 24v relays. The wall switches look a bit goofy and everytime I turn on a light you here the relay clunk in the fixture above. There is a single transformer that powers the system located in the basement near the electrical panel. My question is what was the electrician thinking when he installed this system? What are the advantages to this system? I know the disadvantages but would like to hear more info on the topic. Is this a rare type of system, I have never seen it before but people do things differently in different parts of the country...

 

One advantage is that wire for 24 volts is cheaper than wire for 120 volts, and that wire (being smaller) is easier to run.

 

I agree about the wire size-and would add that it can typically be a multi conductor thermostat wire or equivalent for multiple switching stations which can offer other features such as digital readouts of various other functions in the house.

I, and am sure that many of you others, have seen similar systems using relays controlled by low voltage thermostats for electric heat. While this too can offer some head scratching, I'm sure that this as well was installed with good intentions.

 

I once saw a similar system installed with a "house of the future" intent. The relays could all be controlled from a panel in the basement which could be attached to mechanical timers, switches could be reconfigured to operate different fixtures, etc. Although the replacement relays for that system cost about $12 each, so I can't imagine the the price of 14/2 is that much greater than low voltage wire with relays.

 

This is one reason why I frown on new gee whiz products that require non-standard installations. How many "Cutting edge" technologies have never caught on throughout time. I am personally wrestling with how to control lighting scenes in a house with dimmer packs without having to wire something too non-traditionally. The main problem with something like that is 10 years later when it breaks (and it will break...everything does) will the unit still be aviailable for replacement? Or will extensive rewiring be required to rewire the system to replace the unit with something else, even if it is just traditional dimmers or switches. I have worked on several systems like the one described. Eventually, the switches and/or the relays fail and need replaced. If I remenber right, neither was easy to come by. If the system was broken, I would contact an electrical firm with some history in the area. There are probably other houses in the neighborhood with similar systems and someone has already worked on those. Sorry your "wiring of the future" is just a footnote of "wireing experiments of the past" Good luck.

 

LoveBoatCaptain,

You don't say what the square footage of your house is or how elaborate the lighting system is but here is what I would do.

As you get familiar with what switch/s controls which light/s, if there are any 3 way switching systems etc, start making mental notes of where they are and how difficult it would be to get into the wall space with new wire from the light. Are there any alternative spots you could switch from and how difficult it would be to get wire there also.

I agree with scott e.-what happened is done but sooner or later you will be faced with replacing something somewhere. I'd put my money into a more traditional switching system. For all intents and purposes you could start on that now, in phases, a little at a time-if that transformer goes or relays start to fail you don't want to get into a band-aide/replacement mode.

 

Those systems were often installed in "better houses" back in the late '50's and early '60's. The advantages were not so much the economy of running small wires (well, that WAS a way to save money, but that's not what they were going for), but to be able to provide central control of all the lights in a house. Often, remote stations with two lighted dials were installed in the master bedroom or foyer areas so you could dial up any circuit in the house and operate it. I believe GE was a popular brand of these systems.
I would check with established electricians in your area, as they might know some of the old guys who may have installed or worked on those systems.
I think they were a neat concept, but as Scott pointed out, they are now nonstandard systems. Back in the day, however, they were really cutting edge.

 

Holy smokes! You are right, the bedroom has what looks like a variable speed controller of some type in it above where the bed would go. This is going to end up being a wiring nightmare! Three way switching to every single fixture, can that be right?



Sounds like fun anyway, nothing I like more than figuring out overly complicated circuits...

How many walls am I going to have to open...!

 

Just curious...
Why do you want to change the system? Are you having a specific problem with it? I'd leave it alone if it works.

 

Well I don't get possession of the house for a couple more weeks. But I think you are right Andrew, why change it if it works...