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What are those strange looking wall switches in houses from the 1950s and 1960s?
Monday, August 6, 2018
Low Voltage Switches
They are low voltage switches. The ones in the photo above were made by Remcon and have a retro-futuristic look reminiscent of the Jetsons TV cartoon show of the same era. Similar low voltage switches were also made by GE, Bryant, Sierra, and Touch Plate.
Advantages and Disadvantages
Although the wiring at the switches is low voltage, they control regular 120-volt lighting, receptacles and appliances via electronic relays at another location. A central transformer steps the 120-volt alternating current (AC) down to 28-volts direct current (DC), which enables the use of three very thin #22 wires—shown in the photo below in an the attic—which are easier to run than standard NM-cables.
That’s the advantage of this system, but the disadvantages are that relays and transformers have a much shorter lifespan than regular wall switches, are significantly more expensive to troubleshoot and replace when they fail, and the original equipment is no longer manufactured.
Replacement
Replacement low voltage switches are still made and you can visit the Kyle Switch Plates website at www.kyleswitchplates.com for more information. We recently saw replacement switches in a 1950s house that resemble a regular toggle wall switch, but are recognizable as low-voltage because the toggle lever sits in a horizontal position, like in the photo below.
Kyle will also help you identify which manufacturer’s product you have. At some point, as components of a 50+ year-old low voltage switch system begin failing more often, a homeowner has to decide whether to keep buying pricey replacement parts or write a one-time much bigger check to rewire with standard modern switches. You cannot simply change out the switches and run 120-volts through the old #22 wires.
Also, see our blog posts How does a three-way switch work? and Are wall light switches required be "up" for "on" and "down" for "off”? and How can I figure out what a mystery wall switch does?
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Here’s links to a collection of our other blog posts about ELECTRICAL WIRING:
• Which house appliances need a dedicated electrical circuit?
• Can a short circuit cause a high electric bill?
• What is the maximum spacing requirement for securing NM-cable (nonmetallic-sheathed cable)?
• Is it alright to just put wire nuts on the end of unused or abandoned NM-cable or wiring?
• What causes copper wires to turn green or black in an electric panel?
• What are typical aluminum service entrance wire/cable sizes for the electrical service to a house?
• What could cause an extremely high electric bill?
• Can old electrical wiring go bad inside a wall?
• What is an open electrical splice?
• What are the most common electrical defects found in a home inspection?
• What is the life expectancy of electrical wiring in a house?
• What is an "open junction box"?
• How dangerous is old electrical wiring?
• I heard that aluminum wiring is bad. How do you check for aluminum wiring?
• What is "knob and tube" wiring?
Visit our ELECTRICAL page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.
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