Control/Dimming Orange Goo on Dimmer Resistor Pots

[RileyChilds]

we have a strange orange goo on our dimmer pots! We were wondering what they were! There is a picture below with the pots highlighted, any help appreciated.
Also could this be causing an issue with our LumaNet 408 CP panels?

Dimmer info:
Model: NSI (Leviton) 2408 CD
This is the protocol card

~Riley Childs

 

[JD]

What I am seeing looks like trimmer pots, which have their value set during alignment at the factory.

Two possibilities:
1) A strange lubricant was injected in them at the factory.
2) A fixing paint was dabbed on them once the value was set at the factory.

#1 is unlikely, #2 is very likely. It is very common that once a critical value is set, a dab of paint or other locking agent is applied to the pot. These appear to be trimmer pots.

Now, your second question- You call it "goo" which is interesting. Usually, fixing paint is hard, like nail polish. I can't help wonder if the paint used reacted with the lubricant in the control to change it's composition. If this is the case, all bets are off as we do not know how conductive or corrosive the "new" goo is. So, it could affect operation.

Basically, a trimmer pot is a thin layer of carbon deposited on a wafer with a variable taper made of metal. In all cases, there is also a light grease like lubricant to inhibit oxidization as well as smooth out the feel. Strange orange goo is not a standard part of the assembly

 

[FMEng]

JD has it right, as usual. The "goo" is to hold the position of the pot during shipment. It also clues the factory to someone messing with the trimmers if the paint is broken when it comes back for warranty service. This is commonly done and it shouldn't hurt a thing. Other manufacturers sometimes use sticky dot labels for the same purpose.

 

[church]

FM and JD are correct.

I have seen this "strapping" done with a number of materials: paint, translucent coloured varnish, epoxy, RTV (silicone) and a coloured rubbery compound