Doorbell Continuously rings- (but not a short)

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You seem to be agreeing with Trader and disagreeing with your previous post. But you don't say so and I can't tell for sure.
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First reverse the wires to the switch. Failing that, then +1
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On Thursday, June 19, 2014 5:52:39 PM UTC-4, Pico Rico wrote:

That's what I would do.
An LED is a Light Emitting Diode. A diode is a device that transmits in one direction. It's essentially a short in that direction.
Whoops, that's not gonna work, is it? It shouldn't transmit at all in the other direction, unless you're above breakdown voltage, which you probably are.
Never mind.
Something about that circuit is making a switch that should be Normally Open act as if it were Normally Closed. The diode sounds likely. You could just snip the diode wire. That would be a good test.
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On Friday, June 20, 2014 10:25:35 AM UTC-4, TimR wrote:

It's also AC, not DC.
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There is no basic differance in a LED and any other diode. Within the voltage/current ratings a LED acts just as any other diode does except it often emmits light.
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On 06/20/2014 09:41 AM, Ralph Mowery wrote:

True, although a LED has a low reverse breakdown voltage (just a little higher than the forward breakdown voltage). The series resistor protects it during both half-cycles of the AC.
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Mark Lloyd
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On Friday, June 20, 2014 1:28:04 PM UTC-4, Mark Lloyd wrote:

Yeah. The LED sounds less likely now that I think about it. It wouldn't act as a short unless the current limiting series resistor had failed, and if that happened the LED should burn out and go open, stopping the chime.
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On 06/20/2014 02:45 PM, TimR wrote:
[snip]

Once I accidentally connected a LED to 12V without a resistor. There was an immediate POP sound and half the plastic around the LED disappeared.
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As others have already mentioned, you probably bought a lighted button. The filament in the bulb is conducting enough current to trigger your doorbell.
I encountered this same situation a few months ago at my in-laws. They have a battery operated doorbell that wouldn't support a light anyway. So I just cut the leads to the light on the button. It works fine now.
Anthony Watson www.mountainsoftware.com www.watsondiy.com
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