Home>Discussions>ELECTRICAL & LIGHTING>Odd 1950's - 60's Low Voltage Switch to Relay to Plug
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spike236
Odd 1950's - 60's Low Voltage Switch to Relay to Plug

Hello All,

This is my first post here but I have been reading and getting great advise from this forum for a long time. Thank you.

I recently bought a house the was built in 1957 in Southern California, in trying to upgrade some aspect I wanted to change to decorator-style switches. What I found was very interesting.

This switch controls a plug behind a couch.

I pulled the switch out of the wall box and it was very thin wire. Looks like Thermostat wire. 3 wires (red, white, black) with a gray sheathing. The switch seems to be a momentary switch. The switch sits in a neutral position, when you push up it turns power on to the plug, then it returns to the neutral again. Same with off.

The very thin wires have 6 volts in the lines when you push the switch to turn power on or off. These Thin wires connect to what seems to be a relay in the wall at the plug. The relay has the full load (120) power coming into it and the 3 thin wires. When the switch is pressed up the relay allows full power to the plug. The Relay seems to be rated to 5amps, which seem odd in itself since a vacuum would pull more than that. All the swtiches and fixtures are wired this way, except a new addition which is more conventional. The switches for the hallway light are the same with the 'Relay' set up above the fixture.

The question: Are these switches made anymore? Are they made in modern designs? Are they Safe? Should this all be replaced to Romex? (not ideal given cost and plaster walls)

Does anyone have a recommendation or a source for these type switches/replacement parts?

I appreciate your help in advance.

Much thanks,

Mike

JLMCDANIEL
Re: Odd 1950's - 60's Low Voltage Switch to Relay to Plug
Re: Odd 1950's - 60's Low Voltage Switch to Relay to Plug
spike236 wrote:

Hello All,

This is my first post here but I have been reading and getting great advise from this forum for a long time. Thank you.

I recently bought a house the was built in 1957 in Southern California, in trying to upgrade some aspect I wanted to change to decorator-style switches. What I found was very interesting.

This switch controls a plug behind a couch.

I pulled the switch out of the wall box and it was very thin wire. Looks like Thermostat wire. 3 wires (red, white, black) with a gray sheathing. The switch seems to be a momentary switch. The switch sits in a neutral position, when you push up it turns power on to the plug, then it returns to the neutral again. Same with off.

The very thin wires have 6 volts in the lines when you push the switch to turn power on or off. These Thin wires connect to what seems to be a relay in the wall at the plug. The relay has the full load (120) power coming into it and the 3 thin wires. When the switch is pressed up the relay allows full power to the plug. The Relay seems to be rated to 5amps, which seem odd in itself since a vacuum would pull more than that. All the swtiches and fixtures are wired this way, except a new addition which is more conventional. The switches for the hallway light are the same with the 'Relay' set up above the fixture.

The question: Are these switches made anymore? Are they made in modern designs? Are they Safe? Should this all be replaced to Romex? (not ideal given cost and plaster walls)

Does anyone have a recommendation or a source for these type switches/replacement parts?

I appreciate your help in advance.

Much thanks,

Mike

Make sure the relay you use is a latching relay. As you noted the switch is momentary. I have worked with these systems they are safe but used for lighting loads. as you said the outlet was behind the couch used for a table lamp.Any more questions? :)

spike236
Re: Odd 1950's - 60's Low Voltage Switch to Relay to Plug

Thank you Jack and Harry. I really appreciate the help.

Mike

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