Adding extra LCD console garage door button..

[udunnome]

I have Sears Craftsman 139.53918D Garage Door Openers which are belt driven with battery backup. The openers came with a "Smart Control Panel" (Sears part number 41A6317) pushbutton which looks very similar to the LiftMaster Smart Control Panel 398lm.

They are backlit LCD consoles that include some pretty cool features like motion lighting, on-board lighting, time, temp, and on-board programming. (No more climbing the ladder to program remotes).

I had second door control consoles with my previous openers near the entry to the house. Due to my garages layout, I really want the extra second (and more advanced) consoles.

When I install the extra consoles I purchased, the main console goes blank, resets (time and settings), and dims considerably. Sometimes they work, sometimes they don't. When I go back to a simple door bell button, I have the same issues at each button press, but the main console lights aren't as dim. I'm sure there isn't enough power supplied by the opener for 2 fancy consoles.

The simples answer is... buy the auxillary button that Liftmaster or Sears says, but I really want/need the same consoles at each location. It can't be done is never an acceptable answer.

I understand basic switch and contact closer, but these consoles are a bit more advanced. How would I build a circuit to provide addequate power to TWO of these advanced consoles per opener?

Any advice or guidance is GREATLY appreciated.

 

[NitroPress]

I have what looks like the identical controller on my LM3800. I don't think it's just a matter of the supply power to the controller, but might be an actual interference of their operation. These controllers are kind of weird in that they use a single wiring pair to provide power (usually as 6-24V DC) and send the control signals over the same wires, using different methods - some use a resistive ladder (old school) or use a control frequency of 20-50kHz to carry the signals back to the GDO. It's the prior method that would interfere with each other on the same wiring pair.

If someone knows the answer, please do post it - otherwise I was going to do some digging both for this answer and to satisfy my own curiosity.

 

[Greatbear]

I have the Chamberlain versions, and I too experimented with paralleling the controls with no luck, but I expected as much. The controls use a pair of wires not only for power, but bidirectional data as well. The openers are also designed to see a shorting of the two wires as an old-school method of controlling the door with a simple switch. In the case of one of my pair of doors, I have a standard button next to the door, and both feature controls together between the second overhead door and the entry door. Pushing the standard button will open or close the door, but will also "reset" the feature control because of power interruption. I experimented with resistors in series with the standard button switch, but that simply did not work. Any time the door is operated by a simple contact closure rather than a serial data stream, the control will reset, losing the time settings.

You can buy a set of wireless wall remotes that duplicate the various button features as well as look somewhat similar, but they won't have the display.

 

[gatchel]

I called Liftmaster about my LM3800 and wanted to add another Smart control panel. They said no. The 3800 is designed to only work with one smart control panel. I would have to assume that your sears operator would be the same judging by your post.

 

[udunnome]

I called Liftmaster about my LM3800 and wanted to add another Smart control panel. They said no. The 3800 is designed to only work with one smart control panel. I would have to assume that your sears operator would be the same judging by your post.

Thanks guys! Good to know I'm not alone!

Yes, I did call them as well and they told me the same thing.. but I'm not ready to accept that without trying a little harder. I already bought the extra consoles..

 

[dipper]

Thanks guys! Good to know I'm not alone!

Yes, I did call them as well and they told me the same thing.. but I'm not ready to accept that without trying a little harder. I already bought the extra consoles..

Sounds like somebody needs to get a hold of the schematic for the control panel to see if/how it can be modified. Sounds like you need a separate power supply for the control/display logic and the pushbuttons.