New to the field. Interested in your advice.
It’s a common issue that the wires in a outdoor underground pull box get wet, corrode and over time causes a short.
I was wondering if they make a plastic bag or something that goes round all of the wires and protects them from water coming in through the pull box lid. Any suggestions would be appreciated. Thanks.
If you read the label on the wire nuts you are using it will say “dry location only”. You must use all electrical components according to their instructions.
Use waterproof terminations. The wiring itself must be rated for wet environments such as RHW or THWN. There are waterproof wire nuts. They work so-so. You can also buy heavy wall adhesive lined heat shrink and heat shrink butt splices. You can use crimp lugs and bolt it together then tape like a motor…2 wraps varnished cambric, 2 wraps rubber splicing tape, 2 wraps vinyl.
As far as corrosion goes a proper termination is a gas tight connection. You should be deforming the copper/aluminum to the point where you crack the oxide that is naturally on the metal (even if you can’t see it) and squeezing it so hard that you cold weld the two metals together. If you don’t the joint will heat up and fail prematurely. Even then you can improve things by using electrical joint compound.
In coastal and swampy areas the only time a vault isn’t full of water is when you put a trash pump in and suck it down. May as well assume wiring is permanently underwater. We have no problems with it as long as you take steps to control it.
