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Green liquid from wiring
2

Green liquid from wiring

Green liquid from wiring

(OP)
On a couple of occasions people have reported a green liquid coming from electrical fittings in houses.  It is described as being bright fluorescent green.

Is anyone familiar with this phenomenon, and can you explain what causes it?

RE: Green liquid from wiring

Seen that in humid areas. Most likely verdigris (from copper and brass in armature) or similar substance mixed with condensing water or water seeping through cable. Open up and clean insulators (cut the power first!). This could be the beginning of local heating due to electrolysis and creepage.

RE: Green liquid from wiring

In some cases green discoloration can be caused by off-gassing material used in cable/wire conductor jacket.  Use of PVC insulation on wiring besdes giving signs of discoloration can also form a plastic coating on metal contacts (relays).  Recommendation, see if wire insulation contains PVC.  

RE: Green liquid from wiring

I have seen this green liquid directly at the outlet.  Example:  basement GFI outlet, 4 feet above floor level, mounted on an interior wall, copper wires in conduit feeds the outlet from above.  The basement is dry and has never flooded.  The basement sump pump plugs into this outlet.  When you unplug the pump, there is noticeable quantity of bright green "gell" on the female GFI sockets and on the male plug.  I realize that copper turns green when exposed to moisture, but this "green jello specs"?  I have seen this in several basements.

I have been assuming that this is copper oxidizing onto some contact grease that the GFI people put on the female contacts.  But I really don't know.

RE: Green liquid from wiring

Sounds scary...

RE: Green liquid from wiring

I am an EE working for a company that makes GFCIs and extension cords.  I've never seen any green liquid in any of our stuff returned from the field.  But I have seen green corrosion on cord cap blades that have been exposed to dampness or water for a long period of time.  The most common alloy used for extension cord blades and GFCI recept clips is half hard cartridge brass  (70% Cu, balance Zn)  So the green stuff is copper oxide.  If it is liquid, it's probably water mixed with the oxide.  You'd be surprised how far water can wick down a cable...

That's my guess.

RE: Green liquid from wiring

I used to commission building automation systems, spent a lot of time in the field. Could this be the goo the electricians use to lube the cable when its pulled through pipe.....? Its bright yellow when its in the tube, gets greased on the cable as its pulled.

RE: Green liquid from wiring

That is what I thought of as well. Some are even bright green to begin with, such as Green 80 from Greenlee Tool. It is a waxy soap like bright green goop. If the outlet box in question was top fed via conduit of any sort, the installing contractor may have been a little too generous with the lube compond and it later flowed down into the box when it got warm.

If the outlet is wired with NM cable however (no conduit), I agree it is most likely corrosion of some sort.

"Venditori de oleum-vipera non vigere excordis populi"


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