Garage Door Opener Control Board

[mostxn]

So I have a bit of a problem..
I have an ancient Sears garage door opener from the 70's, that has an electro magnetic relay to control the motor, and a thermal switch to keep the light on for approx 90 seconds. I have 2 openers, this Sears, and an old Overhead Door that has the same controls in it. My Sears opener's relay is failing (I have to press the button 3-6 times to get the door to start, but I can hear the relay clicking when I push the button.)
What I want to do is build a single PCB that can control the up, down, and stop functions of the motor, and also keep the light on for 90 seconds or better after the motor has stopped. (I would like to make this adjustable, but it's not required.)
I know I need 2 relays for the motor, a relay for the light, and some misc electronics. But I don't know what I need, or how to assemble this. I have schematics for both openers, so connecting them won't be a problem.

Written instructions as well as a visual schematic would be a big help.
Thanks!

 

[OldTechie]

If you can hear the relay clicking, but nothing happens, then you probably need to burnish the contacts on the relay. Use 220 or 320 grit emery to burnish the contacts. Use electrical contact cleaner to clean all the grit and carbon from the contacts after burnishing.

There might be an adjustment inside for the light delay. Otherwise, it could be a high value capacitor inside that sets the delay. If you can identify that, you should be able to replace it with a higher value to make the light stay on longer.

Cheers,
Dave M

 

[4pyros]

You should have the safty beam too. Andy

 

[mostxn]

Dave: it probably would fix the machine, but as these parts are getting harder to find, and both of these machines have been around and operating longer than I've been alive, I'd prefer to upgrade them to a control board, then if a component fails, I can just fix it with a little soldering.

Andy: ideally, yes, I would like to make them able to accept some type of either universal residential stye sensor, or possibly a modular commercial style sensor. But for now, I just want to make a board that will keep me from shelling out $150+ on a new opener, plus have the "I did that" bragging rights, even if it is something as mundane as my garage door openers.

 

[4pyros]

mostxn; Ok than you should at least have some current limiting to protect agenst a stalled motor. Do you have remotes to open and close them or just the button inside? Can you give us the modle number for the sears unit? Andy

 

[mostxn]

Andy,
The Sears is a 139.654100. It has one analog transmitter that signals the receiver, built into the wall switch. This is connected to the opener on a 2-wire 24VAC connection
The Overhead Door is model R80Z. It has an external analog receiver stashed inside the case, 3-wire 24VAC connection (pwr/com/sig). The R80Z's push button terminals are also 24VAC. Both of these machines will need 24VAC controls, 110VAC mains in and out to the motor.

Oh, and the thermal light delay may be a bit tricky..
It has three connections to the opener: two are the connections that close to switch the light on, while the third is a thin wire that heats up to flex the lower reed over to touch the drop down from the upper reed, closing the circuit, and turning on the light(s). This wire begins heating when the motor is started, and (depending on temperature) usually has turned on the light(s) near mid cycle.

 

[4pyros]

I cant find much info on these. Can you list the wires that go to the board?

 

[mostxn]

I don't remember what's on the relay, and it's a bit late for me to go look at either of them, but I can tell you the wires I know:
4 from the motor: 2 for open, 2 for close
4 limit wires: 1pr open limit, 1pr close limit
3 for light: 2 for switch and 1 for heater
3 for radio: red, black, blue (trig/com/pwr)
2 per light socket
Hot, neutral, and ground from mains,
Theres a 110vac to 24vac transformer
Electromagnetic relay
Thermal light delay
Two NO limit switches
One NO master power cut off (on OHD unit only)
Then there's a reversing switch on each.
On the Sears it's tied to a pulley that slides side to side and is tensioned by two screws to independently control up and down force.
On the Overhead Door, it's a switch on the rail that trips if the openers rails and head arc when the door hits something. This is set with a spring tightened by a wing nut.

I used to work for Overhead Door, so the opener end isn't a problem. I just am lost when it comes to making the electronics. I considered scavenging a control board off an opener in the local door company's trash pile (I've since moved from Houston, Texas to Seattle, Washington, so I'm lacking my connections for parts) and trying to bodge something together, but the boards I find all have custom connectors, and wiring harnesses that didn't match schematics I found online. Easiest thing for this is just make a controller, then I can adapt it to either machine. Also, if I can figure it out, it would give me room to customize the opener, or like Andy's suggestion, add safety sensors to a machine that is a truly reliable machine, just outdated.

 

[Shyamal]

attach circuit diagram,,,,,,,,

 

[4pyros]

mostxn;

4 limit wires: 1pr open limit, 1pr close limit

Are the limits on the drive?

3 for light: 2 for switch and 1 for heater

Can you post a pic of this setup?
and a pic of the board? Andy

 

[OldTechie]

OK, let me offer this alternative. Still will cost a bit, but nothing like a new opener. Check out one of the 315MHz conversion kits at Home Depot or Lowes. Probably find the best prices on Ebay... .your choice.
The kit provides a new secure receiver and up-to-date remotes. It just connects to the push button connections to operate the opener.. a no-brainer.

Cheers,
Dave M

 

[4pyros]

OK, let me offer this alternative. Still will cost a bit, but nothing like a new opener. Check out one of the 315MHz conversion kits at Home Depot or Lowes. Probably find the best prices on Ebay... .your choice.
The kit provides a new secure receiver and up-to-date remotes. It just connects to the push button connections to operate the opener.. a no-brainer.

Yes but that will not fix the relays that are going bad on his control boards? Andy

 

[OldTechie]

I offered a suggestion as to how the OP could fix the relay in the unit. Burnishing the contacts should solve that problem. A second thought might be that the armature that actuates the contacts is sluggish. A drop of 3-in-One oil on the pivot points will likely cure that problem. The only issue remaining is to lengthen the time the light is on after the opener is actuated. That could be solved by using a 555 timer circuit and a relay.
Cheers,
Dave M

 

[mostxn]

Sorry, things have been hectic here. I'm trying to track down the schematic for the OHD unit, as it was in the bottom of the cover, but has since vanished. I've got another cover in the attic, but it's a matter of crawling up there to find it.
The Sears diagram is in the manual, but I'm still digging thru things since I moved in, so I have to find it. I'm sure it's in a drawer somewhere.
OldTechie: I appreciate the suggestion, but I already have one of those, as I need to find my tuning rods and adjust the transmitter for the Sears opener. It's so out of tune I have to put my bumper within inches of the door and hold the remote out the window... Nothing good to be doing in Seattle! :-D
The relay is working for the most part, except for when it gets cranky and won't let me open the door. The issue with these is that the electromagnet wears down over the years, and eventually doesn't have enough strength to pull the armature back. This is part of what the Sears is doing. Also, it will sometimes pull back, but fail to engage, so instead of the normal "tick tick" that I hear when I push the button, I just get a "THUNK!" and nothing else happens. With the OHD being older than the Sears, I'm figuring I don't have much time left before it starts giving me trouble as well.
I'll keep digging around and try to find the diagram for one of these openers.

 

[jbelectric777]

Just replace the bad relay with a new one from Radio Shack, even if it doesnt fit just find a way to secure it and re connect the leads, your gonna need a relay anyway because of the size of the motor and its inrush current. If there are more than one set of normally open contacts then buy two relays.

 

[mostxn]

Diagrams, finally...

**broken link removed**
This is the diagram for the old Overhead Door R80 unit. This is how everything hooks up to the relay and the thermal light delay. This doesn't really explain what all I'd like to do, but it covers the basics.

**broken link removed**
This is existing magnetic relay that is wearing out. As I said, this machine was built in the late 60's, so there's no electronic control board.

Hope this helps explain things better.

 

[Kevman]

mostxn: do you have a source for a pulley wheel for the Overhead Door model R 80Z opener? I have one that is still working like a champ but the plastic pulley wheel mounted between the tracks above the door that the cable/chain roll over broke and I can't find one locally.
Thanks!

 

[mostxn]

Unfortunately no. One thing you could do just drill out the mounts for the one that is there, then replace it with a new one on a piece of all thread, secured with nuts and washers. I did that repair to a newer version of this opener once.