# Garage door voltage and button



## Selectiveeye (Feb 1, 2017)

I have a garage door opener circa 1960s. It works fine, but need to change one of the operating buttons. I tried a standard doorbell momentary switch button rated for 16v. It's lighted button burned extremely bright and I knew within days it would burn out. Took 2 days to go out. The button still works, but my fear it that there is a lot more voltage running through it. It even sparks a bit when pressed. So I am thinking because of the age of the opener it probably has a higher voltage running to the buttons. I tried to test the voltage, but couldn't get a decent contact before the opener would engage and open. The only specs I could get off the unit was that input v is 110. Recommendations for a safe button ? Should I not worry?


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## Oso954 (Jun 23, 2012)

Why a doorbell switch ?

The garage door opener companies make universal opener switches.
Both of the big boxes have them in stock next to the openers. You can also find them at larger hardware stores.


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## Selectiveeye (Feb 1, 2017)

The electrical rep at the home center said the doorbell and garage button are the same. All available were rated 16v max. The universal remote button kits you speak of, are not going to handle the higher voltage associated with the older model opener, unless it is powered. I hooked one up several years ago and it burned out within seconds. I had to buy one that also plugs into an outlet. It works fine. But this will not resolved my button need, in an unpowered area.


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## Oso954 (Jun 23, 2012)

You are saying its higher voltage, what is it ?
Use a volt meter and take a reading.


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## bob22 (May 28, 2008)

Best be careful. Might be line voltage you are switching with your doorbell button! Measure the voltage as others have suggested so you know what voltage rating your new switch needs.


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## FrodoOne (Mar 4, 2016)

Selectiveeye said:


> I have a garage door opener circa 1960s. It works fine, but need to change one of the operating buttons. I tried a standard doorbell momentary switch button rated for 16v. It's lighted button burned extremely bright and I knew within days it would burn out. Took 2 days to go out. The button still works, but my fear it that there is a lot more voltage running through it. It even sparks a bit when pressed. So I am thinking because of the age of the opener it probably has a higher voltage running to the buttons. I tried to test the voltage, but couldn't get a decent contact before the opener would engage and open. The only specs I could get off the unit was that input v is 110. Recommendations for a safe button ? Should I not worry?


Do the original buttons have any indications of the operating voltage on them (at the rear)?
Are the original buttons lighted buttons and, if so, do the lights have any indication of the operating voltage?

What is the wiring to the push button? 
If it is "bell wire" and there is no wall box, it "ought' not be 120 V AC. (It should be "Extra Low Voltage" - below 50 V AC.)
If the wire is "building wire" (e. g. Romex) and(/or) it is in a wall box, it almost certainly is 120 V AC.

While the replacement button burned very brightly for a few days, apparantly this did not cause the door mechanism to operate. Yet when you "tried to test the voltage, ... couldn't get a decent contact before the opener would engage and open."


If you use a normal multi-meter to test AC Voltage, it should have a MUCH higher resistance than that of a 16 V doorbell button incandescent lamp - or was it a LED? 
In either case, if the lamp in the doorbell button did NOT cause the door motor to operate, a decent multi-meter should not cause operation of the door motor either.


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## Selectiveeye (Feb 1, 2017)

Thank you for the reply. I am fairly certain it is dc, since there is no box in any of the connections, and they used bell wire. I did not see any indication of power measurements on the other buttons, which are old and we're never lighted. I need a way to test the voltage without activating the opener upon contact. Is there a way? I think I may just find a momentary switch that can handle 36 volts. I can't imagine it is more than that going through bell wire.


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## Oso954 (Jun 23, 2012)

> I am fairly certain it is dc, since there is no box in any of the connections, and they used bell wire.


I don't see how you draw the conclusion of DC from that. Low voltage yes, but the DC is a guess, and probably a false one.

My expectation would be low voltage AC.


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## J. V. (Jun 1, 2007)

In the garage, open up the door opener. 
Look for the transformer.
Read the specs on the transformer or measure the voltage out of the transformer.
Then buy a non illuminated push button that falls into this voltage range. Any button should work as it low voltage and is only momentarily energized*.

When you tell the door to open or close you are not actually doing anything but energizing a contactor that's located in the door opener.
These contactors/relays close and open sending 115/120 volts to the motor. Up and Down.

When you work with any of the operator interface like the push buttons and wireless remotes, you are dealing with low voltage vs the motor power that is 115/120 volts as noted from the picture of your motor.

*One more thing. Since this thing is ancient, I would not discount the 115/120 volts as being used for manual control as well as to operate the motor. 
So use a meter to see what you have. This is important.


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## Selectiveeye (Feb 1, 2017)

My mistake in typing "dc". I meant low voltage ac, so I am in agreement.


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## Selectiveeye (Feb 1, 2017)

So my issue now would be how do I set my meter to take a reading that will not trigger the opener? I tried to read each of the two terminals to each other and it opens the door. I then tried to read from "A" terminal to ground and it triggered the door. Terminal "B" to ground did not trigger the door. Bear in mind I do not know 90% of what my meter does or what many settings mean.


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## Oso954 (Jun 23, 2012)

Per your pic, the meter is set to DC amps, which passes full current thru the meter.

First thing you need to do is move the red probe connection down one hole. It is currently in the DC 10 amps hole.

Next move the center knob 2 positions CCW to the 200 AC volts position (ACV)

The indicator dot on that knob is rather small. If be tempted to enlarge it, color it, or make some other distinguishing mark (black arrow?) so it would be more obvious what the setting is.


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## Selectiveeye (Feb 1, 2017)

Very helpful thank you. I marked the indicator with a black marker. The reading was successful and did not trigger the door. It read 43.6 so is that my voltage through the wire?


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## Oso954 (Jun 23, 2012)

Plus or minus a couple percent. It's precision of display is more precise than its precision of measurement. That's not uncommon with less expensive meters. It should be adequate for all of your DIY uses.

But it answers the question that you are looking for a 48v (or higher) rated switch, for long bulb life. Is the light bulb required or just desired ?


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## Selectiveeye (Feb 1, 2017)

The bulb is not important. Oddly, it came back on today when I was hammering nearby. Weird.


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## J. V. (Jun 1, 2007)

Where are you putting your test leads? You cannot read the voltage of a switch by reading across the switch.
*You have proven something though!*
All you need is a push button. You proved that by making the circuit with your meter. Good job Oso954.

OP get a button. Its all you need.


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## LawnGuyLandSparky (Nov 18, 2007)

J. V. said:


> Where are you putting your test leads? You cannot read the voltage of a switch by reading across the switch.
> *You have proven something though!*
> All you need is a push button. You proved that by making the circuit with your meter. Good job Oso954.
> 
> OP get a button. Its all you need.


And make sure it's not illuminated.


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## Oso954 (Jun 23, 2012)

I'd replace the switch with a momentary switch often used for disposals. I'd most likely use a surface mount plastic box. If the switch is limited to #14 or larger, use a couple of pigtails, then wire nut to the bell wire.
https://www.amazon.com/Eaton-7521W-15-Amp-Momentary-Contact/dp/B00PB98W46


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