Weird device: garage door opener won't close (safety sensor)

[eccerr0r]

Well, it looks like my garage door opener won't close anymore this last time it got real cold. It thinks that there's an optical obstruction. The two parts of the optical sensor have an LED on them - one is always on. The other one is on... but... here's the kicker...

It flickers! It's mostly on but there's some rapid, barely noticeable 'off' times. It's so subtle that I'm not sure if people can easily notice it flickers off.

I can put my hand between the sender and receiver, and the LED will completely shut off.

I tried jiggling the receiver a bit but could not get the LED to stop flickering. I didn't try jiggling the sender because I can't see the receiver while jiggling. I also tried cleaning the optics end with a damp paper towel.

Anyone seen this before?

[stj]

Re: Weird device: garage door opener won't close (safety sensor)

seen white led's flicker, i think it's bond-wire failure.

[eccerr0r]

Re: Weird device: garage door opener won't close (safety sensor)

It uses a green LED, but it seems that the flicker coincides with the "detection" of something interrupting the beam and the closure stops.

[eccerr0r]

Re: Weird device: garage door opener won't close (safety sensor)

It's a little warmer today, and it worked today... aahh do we have ... bad caps in the garage door opener???

[CapLeaker]

Re: Weird device: garage door opener won't close (safety sensor)

how old is that thing?

[eccerr0r]

Re: Weird device: garage door opener won't close (safety sensor)

probably at least as old as the house, which would be on the order of 20-30 years I would guess.

[redwire]

Re: Weird device: garage door opener won't close (safety sensor)

If you can get the beam transmitter and receiver apart, surely the electrolytics are old. The IR transmitter LED does fade with age in designs that drive them hard.
Working principle is to pulse an IR LED at many kHz, so not as sensitive to sunlight and AC lights, over to a photo-transistor detector circuit.

Many (two-wire) garage door openers have the safety-sensors and open/close + light on/off switches all on the same two wires. Those use a big party line- you have power, data for three switches, all on two wires.
Depends on the make of opener.

I've also had Marettes make a bad connections with copper wiring corroding, close to the concrete floor, so I just soldered them.

[stj]

Re: Weird device: garage door opener won't close (safety sensor)

at that age, i would replace all the caps and led's and give it a damned-good resolder.
also, any relays you can open i would clean the contacts with a bit of card soaked with IPA.

[eccerr0r]

Re: Weird device: garage door opener won't close (safety sensor)

The garage door infrared safety transmitter/receiver - have more than just the LED and phototransistor/photoresistor? Hmm...might have to open them up, I thought they were fairly dumb devices, just the sensor and LED, and the control comes over the wire...

[sam_sam_sam]

Re: Weird device: garage door opener won't close (safety sensor)

But it could also be that controller board might be having issues

[eccerr0r]

Re: Weird device: garage door opener won't close (safety sensor)

It's a bit warmer today and the LED in the sensor block is solid green/on instead of flickering... Yow...

Works fine today...

[budm]

Re: Weird device: garage door opener won't close (safety sensor)

Hair dryer and canned Air duster are your friends.

[eccerr0r]

Re: Weird device: garage door opener won't close (safety sensor)

I'd have to partially disassemble the opener to really test it, and with it up on the ceiling hooked up to metal bars, it will be a PITA. And I really need to get some freeze spray/"compressed air" duster someday...

Incidentally, the light bulb in my garage door opener is about to go. It too is flickering badly, probably due to poor contact of the filament. Unfortunately a CFL is not a good match in there, the power savings due to the duty cycle of a LED in there is probably not worth it, so I have to grab an old incandescent (ideally heavy duty) from somewhere to replace it.

Or just leave it out.

[redwire]

Re: Weird device: garage door opener won't close (safety sensor)

Don't use CCFL lights on your garage door opener.
They make too much RFI and since the lamps are about a foot away from the receiver's antenna, you may wonder why the remote does not close the door... when the lamps are on.

Instead, manufacturers advise using rough-service incandescent bulbs.
I haven't tried LED lamps, they should be better, but who knows what they are like for RF emissions at 315-433MHz

[eccerr0r]

Re: Weird device: garage door opener won't close (safety sensor)

fsck, it's bitterly cold again. Problem showed up again.

[stj]

Re: Weird device: garage door opener won't close (safety sensor)

Don't use CCFL lights on your garage door opener.
They make too much RFI and since the lamps are about a foot away from the receiver's antenna, you may wonder why the remote does not close the door... when the lamps are on.

Instead, manufacturers advise using rough-service incandescent bulbs.
I haven't tried LED lamps, they should be better, but who knows what they are like for RF emissions at 315-433MHz

get the cheapest chinese led lamps you can find.
if they use a capacitive dropper they wont cause interference.

[CapLeaker]

Re: Weird device: garage door opener won't close (safety sensor)

LED's work fine in mine.

[goontron]

Re: Weird device: garage door opener won't close (safety sensor)

fsck, it's bitterly cold again. Problem showed up again.

Ain't bitter till its south of zero.

[eccerr0r]

Re: Weird device: garage door opener won't close (safety sensor)

The garage door opener begs to differ...

[momaka]

Re: Weird device: garage door opener won't close (safety sensor)

Well, it looks like my garage door opener won't close anymore this last time it got real cold. It thinks that there's an optical obstruction.
...
Anyone seen this before?

Funny this thread popped up now.
I've also been having issues this winter with one of the garage door openers as well, and it's the same issue as yours - as soon as I try to close the garage door, it thinks there is something there and can't close. But mine started doing it last fall when it got really muggy/wet one day. I see lots of corrosion on the door rails where my sensors are mounted, so I am suspecting bad solder joints or something conductive has developed on the PCB. I managed to temporarily fix the problem by wedging a box behind the sensor to keep the wire steady. It makes the sensor work most of the time. So on that note, I definitely think I have contact problems. But yours definitely sounds like a classic cap issue. I guess we will see when it gets a bit warmer and you tear it apart?