Dielectric grease
#12
#13
#14
I rebuilt some D1 seat switches and applied a thin layer on all the contacts. All worked well at first, but after a while I re tested and approx 30% did not have full function. I was under the impression that he grease was interfering with the electrical connection. Thoughts?
In a connector full of dielectric grease, there's a contact point between the two metal prongs where current flow. That contact point is surrounded by grease and so metal is not exposed to air and moisture.
It's a little different in a switch because the metal parts move apart from each other, then come back together again to make contact. So the grease is somewhat kept constantly rearranged inside. Now it the switch was perfectly clean when you applied the grease it shouldn't matter.
But if there were some foreign objects now they can be moved by the grease and interfere with the contact itself. Before, if a contact had a foreign object in it trying again would dislodge it. Now, in the same situation the grease will hold it there for some time.
#16
Actually, dielectric/silicone grease is bad for switches where there may be arcing.
"Silicone grease should not be applied to (or next to) any switch contact that might experience arcing, as silicone can convert to silicon-carbide under arcing conditions, and accumulation of the silicon-carbide can cause the contacts to prematurely fail. (British Telecom had this problem in the 1970s when silicone Symel® sleeving was used in telephone exchanges. Vapour from the sleeving migrated to relay contacts and the resultant silicon-carbide caused intermittent connection.)" - wikipedia
I think the seat switches switch fairly high-current circuits. I know they operate at least one relay (which would carry most of the current for that circuit) per seat under the driver's seat, but if I recall correctly, they do switch a 30A circuit. At 12V, that will arc.
"Silicone grease should not be applied to (or next to) any switch contact that might experience arcing, as silicone can convert to silicon-carbide under arcing conditions, and accumulation of the silicon-carbide can cause the contacts to prematurely fail. (British Telecom had this problem in the 1970s when silicone Symel® sleeving was used in telephone exchanges. Vapour from the sleeving migrated to relay contacts and the resultant silicon-carbide caused intermittent connection.)" - wikipedia
I think the seat switches switch fairly high-current circuits. I know they operate at least one relay (which would carry most of the current for that circuit) per seat under the driver's seat, but if I recall correctly, they do switch a 30A circuit. At 12V, that will arc.
The following users liked this post:
abran (01-02-2015)
Thread
Thread Starter
Forum
Replies
Last Post
Love U Landie
General Tech Help
4
02-04-2013 03:17 PM