I've just been attempting to get my Waeco copy 50l freezer down to -20C and noticed that it did not want to go lower than -13C. (ambient +35C)It was connected to a battery which is then connected to an 80w solar panel. On checking the solar amps out of the regulator I noticed I had zero despite the sun shining and everything plugged in correctly. I then disconnected the Anderson plug from the regulator and noticed that it was pretty hot and the + connector was not sitting correctly in the plastic body with it's 'hook' behind the spring. Also noticed was that the rubbing surfaces of the connector was badly eroded which probably helped in heating the plug and also forcing the+ connector off the spring.
So, it looks like some maintenance on the connectors will have to be a regular happening - this connection has been used for the past 2 years, disconnected at least 100 times, lubricated with silicone grease but unfortunately because it is carrying up to 6 amps when connecting it is causing erosion and pitting the rubbing surfaces. Answer I suppose is to cut the power but adding a switch adds another 2 surfaces to erode. If I file the eroded surfaces smooth I remove a lot of meat and then the hooked end will fail.
Anyone have any suggestions....please.?
Regards
Denis
PS....forgot to mention the Anderson Plugs like my freezer are copies.
-- Edited by hako on Thursday 18th of February 2016 04:50:59 PM
The genuine Andersons will last many years. They are made from UV resistant polycarbonate. Just don't get fuel on them.
The copies may be made from non UV resistant material and could fail in a year or 3.
Anderson Plugs, by design, are supposed to be plugged and unplugged regularly so the rubbing action of the terminals keeps then clean and free of corrosion.
Thanks for the replies - I do have one or two genuine Anderson plugs mixed among the copies and these show signs of wear such as grooves and scratches no doubt from the silicone grease which holds grains of sand etc!!! They do not have the erosion but maybe they have not been disconnected when carrying current.
Maybe genuine is the way to go...stronger springs maybe.....better metal in the connector maybe.....maybe they should not be disconnected when carrying current but then how are they different from a switch?
Can anyone comment on the mayby's? - I've checked the manufacturer but they do not go into technicalities basic though they may be.
I've just been attempting to get my Waeco copy 50l freezer down to -20C and noticed that it did not want to go lower than -13C. (ambient +35C)It was connected to a battery which is then connected to an 80w solar panel. On checking the solar amps out of the regulator I noticed I had zero despite the sun shining and everything plugged in correctly. I then disconnected the Anderson plug from the regulator and noticed that it was pretty hot and the + connector was not sitting correctly in the plastic body with it's 'hook' behind the spring. Also noticed was that the rubbing surfaces of the connector was badly eroded which probably helped in heating the plug and also forcing the+ connector off the spring.
So, it looks like some maintenance on the connectors will have to be a regular happening - this connection has been used for the past 2 years, disconnected at least 100 times, lubricated with silicone grease but unfortunately because it is carrying up to 6 amps when connecting it is causing erosion and pitting the rubbing surfaces. Answer I suppose is to cut the power but adding a switch adds another 2 surfaces to erode. If I file the eroded surfaces smooth I remove a lot of meat and then the hooked end will fail.
Anyone have any suggestions....please.?
Regards
Denis
PS....forgot to mention the Anderson Plugs like my freezer are copies.
-- Edited by hako on Thursday 18th of February 2016 04:50:59 PM
I assume you have the silicone electrical CONDUCTIVE grease.
About six months ago I was going around the van and truck with WD40 spray and silicone spray. Not thinking I must have used the silicone spray on the 7 pin plug.
A few weeks later hooked up the van and no electrics to van and I instantly had a "flashback" that I used the wrong spry pack. Sure enough I did. I had to use electrical contact cleaner to clean the crap out.
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Why is it so? Professor Julius Sumner Miller, a profound influence on my life, who explained science to us on TV in the 60's.
Dennis why do you lubricate the plugs with a non conductive film of grease particularly silicon grease. Your poor connection and pitting are probably the result. The contact surfaces should be clean and dry for best conduction and as Herks said they are designed to be self cleaning by frequent plugging together and unpluging.
Hmmm....the silicone I use is the white stuff you use to grease electrical plugs so they slide together easily like over sparkplug coils etc and Baz and Alan may be onto something! I googled and found this:
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. Vapor from the sleeving migrated to relay contacts and the resultant silicon-carbide caused intermittent connection.)
So it looks like that is the reason for the pitting and subsequent problems. Thanks fellas.
I used to use a strip of 'micro scrub ' this is a 20 cm strip of a cloth like material that has a rubber membrain. Used on a lot on tarnished contacts ( relay and switches etc ) worked very well with a good dose of contact cleaner. This combination would remove the tarnishon off the contacts with out affecting the plateing ( silver or gold on the better contacts ) never had a comeback.
Radio parts group ( Melbourne ) was the best place to buy it as i don't think jaycar would sell it.
Unfortunately it's not tarnishing but pitting/erosion caused by sparking when connecting the "live" cables. Best I think I can do is remove all the silicone grease etc and then the rubbing action should smooth the contacts out. Probably will need to clean them a few times as I know silicone is hard to remove - will run them dry from now on because they all have grit etc inside the connectors and there is no way of keeping this stuff out of them as far as I can see. I have a BIL who is visiting today and he might have some of that "micro scrub" or similar to use as well.
Thanks again for all the suggestions.
The brand 'CRC' have two types of cleaners on the market that i have used on many contacts.
1/ CRC contact cleaner, this stuff works very well and drys off with no resedude and is what i have used in the last 20 odd years on contacts.
1/ CRC also have a nother cleaner and this was used in valve radios and televisions, also cleanining volume controls etc. this also left a film of the cleaner behind that also helped with the mechanical movement of the contacts. The only down side was not to use it in the high voltage cct of televisions ( horizontal out put stage for one).