Ever since the weather turned cold I have been having problems with the relay tips sticking closed. I use a pair of these modules on my garage door opener. When I pull the module and bring it inside and let it warm up for about 5 minutes or so it starts working and snaps back and forth with no problem. Put it in the freezer for about 10 minutes and no more snap and the tips are stuck closed again.
After disassembly and removing the cover off the relay switch assembly I found that when cold the nylon lever that lifts the contact arm would not move far enough to lift the contact arm to open the tips. After close inspection I found that the nylon arm has a small rib that runs from top to bottom on one side. This rib is located on the center body that is the pivot center of the lever. When it pivots back and forth it has to snap over a matching rib which is stationary (part of the relay body.)
Time will tell if this fix works but short term freezer tests look good right now.
I insert a small piece of folded up cardboard in the contact tips to hold them open. (while operating)
I lift out the pivot lever, it lifts straight up nothing holds it.
If you look at the center pivot area you will see a raised ridge running up and down the body on one side. I trimmed this ridge completely off so there is no contact with its matching ridge on the relay body.
Assembled and placed in freezer. Froze for 10 minutes, removed and the relay operated OK
The only thing that I can see this ridge or detent setup doing is that when the tips are open it will help stop the lever from slipping and causing the tips to close. This may happen if the unit is in an application where there is vibration.
(The lever and spring setup inside is over center and should stay in the open position with out to much problem)
If anyone else tries this please post back here and let us know how it works... or doesn't work.
As always I'm sure this will void the warranty so this mod or any mod is at the end users own risk.
I will have to monitor closely to see if I fixed it or made things worse some how.