Fluorescent lights interfere with Infra-Red devices even when switchedoff!?!?!?

[Chris Lewis]

According to Percival P. Cassidy :

Let me get this right:

You have CF lamps, unconnected with the garage door unit, that appear to cause problems with the garage door unit, and the problem will "initiate" EVEN IF the CFs are off?

I suppose it's very marginally possible that their assessment is correct, but it shouldn't be that sensitive.

A couple things you could try to rule in/rule out: try putting an optical barrier between the CFs and the GDO, or block off the IR sensor so that it only can "see" the directions where the actuators are. Check to make sure that the CF switching actually switches off the hot, not the neutral. Pull the CFs from their sockets and see if the problem persists.

If it were a classic tube fluorescent, the first thing I'd do is make sure the fixture case was solidly grounded and that it was only the hot being switched.

[Percival P. Cassidy]

And I just noticed that the Revision Date on the manual is 10/06/04, whereas the DOM code on the unit is 0903. How on earth did W-D have this thing sitting around for a year before they boxed it up to ship out?

I've still heard nothing from W-D about my replacement parts, but I've emailed them and told them I hope to get a prompt response.

Perce

[John Savage]

Probably in your case, but not always. I live in a block of apartments. The building's stairwell and garage area lights are on a timeswitch--an old fashioned mechanical relay arrangement that goes THUMP when it switches on.

One cloudy afternoon as I felt my way down the stairwell in the half gloom rather than switching on a dozen lights just to go a few flights, out of the corner of my eye I imagined I caught a brief flash of light from a CF fitting I was passing under. Intrigued, I waited, and waited, and discovered to my amazement that every 4 or 5 minutes this globe would give a momentary low-intensity (to my eye) flash of light! It was just an ordinary CF globe that I'd installed.

I have not been able to come up with a satisfactory explanation for this. In case there was a leakage current, I made sure after that to always have at least one globe an ordinary incandescent.

[Don Klipstein]

I have found some CFs to flash from leakage current. Ones with glow switch starters (and magnetic ballasts) may have the starters very dimly glow or flicker a purplish color.

I saw this mainly when I tried switching a CF with the Radio Shack "Plug-N-Power" switching system. The receivers intentionally leak some current to detect whether a load is in place. I suspect CFs could even have extra wear from dimly glowing or flashing when "off" with the "Plug-N-Power" system, since their filaments will not be at the proper operating temperature. Starters may not like to be glowing all the time.

However, I do not expect the much lower leakage currents found elsewhere to cause much wear to fluorescents.

- Don Klipstein ( [e-mail])

[Percival P. Cassidy]

The replacement light unit and motor control board arrived today, but I haven't had a chance to install the board yet. It looks as though they've changed from IR control to RF control for the light: a loop on the circuit board where the IR diode was on the old one.

Still no replacement wall control; the newer ones have a "vacation lock" function, which I think could be very useful.

Perce

[Paul Hovnanian P.E.]

^^^^^^^^^^^^^^^^^ I think this might be the key.

[Paul Hovnanian P.E.]

Do you have a CFL installed in the garage door light fitting?

Its very possible that the (electronic) ballast presents a load that the lamp control circuit (probably a solid state control like a Triac) can't handle.

Its not very likely that the interference is with the IR link but with the lamp control.

[Paul Hovnanian P.E.]

Does the system operate correctly if you remove the CFLs completely?

[Percival P. Cassidy]

On 09/09/05 03:11 pm Paul Hovnanian P.E. tossed the following ingredients into the ever-growing pot of cybersoup:

I didn't try that. I have now received and installed the free replacement light unit and motor-control board, and they work fine -- but the light unit is now controlled via an RF link instead of via the earlier version's IR link. So it's quite possible that W-D had enough problems with fluorescents in garages (surely a rather common situation) interfering with their IR-signalling system (when the fluoro. lights were ON) that they felt obligated to scrap the IR in favor of RF.

Perce

[Percival P. Cassidy]

On 09/09/05 05:26 pm TKM tossed the following ingredients into the ever-growing pot of cybersoup:

I have now received and installed the free replacement light unit and motor-control board, and they work fine -- but the light unit is now controlled via an RF link instead of via the earlier version's IR link. So it's quite possible that W-D had enough problems with fluorescents in garages (surely a rather common situation) interfering with their IR-signalling system (when the fluoro. lights were ON) that they felt obligated to scrap the IR in favor of RF.

Perce

[TKM]

There is certainly no way a fluorescent lamp which is switched off can interfere with any type of control.

However, operating fluorescent lamps can interfere with IR controls. It doesn't seem to be a widespread problem, but I've heard about situations where IR controls used for TV and other A/V systems don't work in rooms with fluorescent lighting. The reason is the frequency of the IR signal. If it is close to or a multiple of the frequency that the ballast sends to the lamp, then the lighting signal will swamp the IR receptor.

TKM

[Paul Hovnanian P.E.]

[snip]

There is one more thing you can check, if you don't mind doing a little research just for the heck of it.

See if any of the lamp sockets into which the CFLs were installed have their hot and neutral leads reversed. The screw threads of a lamp should be neutral.