Ottlite PL-0094 Touch Switch Hack

Geschrieben von: Wayne Seltzer

Kommentare: 17

Schwierigkeitsgrad

Easy

Schritte

Zeitaufwand

20 Minuten

Einleitung

The Ottlite PL-0094 Dual Shade LED Floor Lamp uses a touch switch to turn the light on and off and set the dimming levels.
The touch switch circuit appears to fail in a way that decreases the sensitivity such that the lamp can no longer be controlled.

Amazon 1-star reviews of the product suggest this is a common problem.
And the touch circuit replacement board does not appear to be available for purchase.

However, it turns out the touch sensor still works if one directly touches the contact for the touch sensor.

Simple fix: add a metal washer, machine screw, and nut to the touch switch area.

Werkzeuge

Soldering Iron

Ersatzteile

Schritt 1

Place the lamp horizontally on a work surface
Unscrew the two screws above the control panel that hold the upper and lower parts of the lamp together
Slide up the control panel to remove
Unscrew the two screws that hold the power board in place
Use a soldering iron to gently melt the two plastic studs that hold the touch sensor circuit board in place
Remove the touch sensor button. It's not really an electrical or mechanical button; it's just decorative.
Install a small fender washer, machine screw and nut. Drill a small hole in the center of the control panel where the touch sensor button is placed.
Drill out the bottom plastic stud for the touch sensor circuit board mount.

Schritt 2

Replace the touch sensor circuit board.
Use a small machine screw and nylon nut to secure the touch sensor circuit board.
Be sure the conductive foam is making contact with the screw and nut that is holding the fender washer.
Re-install the power circuit board
Re-assemble the lamp.

Abschluss

To reassemble your device, follow these instructions in reverse order.

Tinte & Feder

Wayne Seltzer

Mitglied seit: 09/11/10

1237 Reputation

17 Kommentare

wayne i found this outtlight in the trash i tried to buy a switch of course there are none, anyway found your post and thought i would give it a try ..and it works thank you for spending time sharing the fix howie

Howard Fitzner -

Glad the fixed worked for you, Howie!

- Wayne

Boulder U-Fix-It Clinic [http://boulderufixiticlinic.org]

Wayne Seltzer -

Once you take the circuit board off of being mounted is there a way to test to make sure the light so works? We can't tell if the circuit board is the problem or not.

Jaclyn -

If you touch the conductive foam attached to the circuit board, you should be able to turn the lamp on/off/dim.

Wayne Seltzer -

Thank you for your helpful guide. I am new to repair and stuck on the 5th step --the two plastic studs that hold the touch sensor circuit board in place--because I can not locate the two plastic studs. When I look behind sensor board, I only see a small white plastic square in the center above a grey round piece of fabric. One end of the white plastic square is attached to the sensor board and the other is attached white plastic housing and it moves in when pressed --is that one stud? I do not see the second stud. thank you. Sue.

sue byrce -

Is there a way I can send a photo of the disassembled sections to help me identify parts above and in the rest of the directions. Thank you.

sue byrce -

Sounds like your lamp has a different design.

A photo would be helpful. If you can take a picture and store it on a web site (http://photos.google.com, http://icloud.com, ...), you can reply with a link to your photo(s).

Wayne Seltzer -

Thank you for responding. It is the PL-0094. I don't have anyway to upload image so I posted the question and image here:

sue byrce -

I would like to hack this for just "touch on touch off" without the dimming function. Is there an easy way?

Bob S -

The user manual suggests that the dimming levels are fixed and cannot be changed:
https://products.ottlite.com/p-463-dual-...
...
3. To power LED settings, slightly touch the switch (E) to achieve the following:
•turn lamp “ON” to 1st brightness setting; touch the switch “once”
•for 2nd brightness setting; touch the switch “two-times”
•for 3rd brightness setting; touch the switch “three-times”
•for 4th brightness setting; touch the switch “four-times”
•to turn lamp “OFF”; touch the switch “five-times”.

...

Wayne Seltzer - 05/10/22

I know. I meant "hack" in the sense of changing the hardware/schematic connections to do something outside of the manual...but maybe the schematic is not so easily understood.

Bob S -

That would be an interesting reverse engineering project.
The guts of the Ottlite electronics is a dimmable fluorescent lamp driver, which is pretty easy to understand.
Maybe some other touch switch circuit could wired into the Ottlite board? Or, even just a simple pushbutton to avoid the whole capacitive touch circuitry, which, apparently, the Ottlite engineers didn't get quite right.
I did this repair for a friend, so I don't have the board to look at. But, if you learn something about this, be sure to let the ifixit community know.

Wayne Seltzer -

I tried the method that you describe. But when I got the Touch Sensor board off and powered the lamp, I could not get the light to come on by touching the conductive foam. I tried several times. I suspect my situation is different and the Sensor Switch board is shot.I don't use the dimming feature, so I am okay with putting in a simple toggle switch. But I am not sure what the maximum voltage the lights can take. Can you tell me if I can switch the 18VDC straight to the lights? I don't want to go through all this only to burn out the lights :)

Dale O.

Dale O. -

I can't find a schematic diagram for the Ott light, so I don't know if there is a workaround to the problem you are experiencing.
Since this is a fluorescent light, it needs high voltage, which is generated by the control board.
If you have a multimeter, you might want to test some obvious things:
- Measure the output of the AC adapter at the barrel connector. Is it 18VDC or so?
- Plug the AC adapter into the Ottlite control board. Is there the same DC voltage on the jack on the control board?

- Any components obviously bad? Burn mark? Swollen capacitors?

Good luck!
- Wayne

Wayne Seltzer -

Wayne, Thanks for the reply. Yesterday I had access to a working lamp. I checked the two circuit boards with a volt meter. The input voltage was 17.5 volts and the output to the lights with the light on, (first position) was 16.8 volts, or about one diode drop in voltage. I don't know if that drop is required or just an artifact of the circuit board. I suspect the drop is not necessary. But just to be conservative, I plan to put a 3 amp diode in series with the lights to provide that voltage drop and install either a rocker switch or toggle switch, depending on what I can get that fits. I saw no sign of a burned out component and the part numbers have been removed from the ICs. They are obviously hiding the circuit details. BTW, the lamp is an LED lamp as you state in the opening to this thread. Thanks again.

Dale O. -

Oh, right, it's an LED!
The proprietary Ottlite control board probably uses PWM (Pulse Width Modulation) to control the brightness -- this is very common with LED lighting.
So, the question is, does the circuit provide current-limiting? An LED directly connected to a DC source will draw as much current as the power supply can provide, which could result in blowing up the LED(s.) Maybe there's a current-limiting resistor on the LEDs board? Or not?

One approach would be to use a 1K resistor in series with the DC power supply and the LEDs. That will probably be too dim.
Decrease the resistor value lower until the brightness seems right.

Wayne Seltzer -

Wayne, thanks. Excellent point. The light fixture itself probably doesn't have any current limiting resistance.

Dale O. -