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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.
 

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36th year apprentice & Floor Sweeper
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I agree. Tape on the wirenuts only help in keeping the water in the wirenut. The only thing that’s going to keep water out is air. The wirenuts need to point straight up. The bigger the skirt on the wirenut the better. As the water rises up, it creates an air pocket under the wirenut. It will still get some corrosion, but some dielectric grease or Noalox will help.

The best trailer lights for my boat trailer, are the ones that are wide open on the bottom. The ones that are sealed with a gasket only last a year. The open bottom ones are molded plastic on all sides except the bottom. They create an air pocket when they go under water. The ones with a gasket always leak under pressure and then just hold the water in.
 

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Big nosed attic troll
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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.
think about what you asked. do things underground get wet......hmmmmmm
 

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Top of the scotchkote can is large enough to dunk a wire-nut connection. What ever connection method you use it has to have the same insulation value as the wire or better when you leave..

I have worked at places where you have 25kv splices in underground vaults full of water and they have been that way for over 30 years. No reason you can not do the same with lower voltages if you take your time and do it correctly.
 

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Chief Flunky
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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.
 

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First question is why are you splicing in the handhole ? We put our spices in the Mast arm or Joint use pole ... that's what the door on them is for !

If you need a splice U/G or in a handhole/manhole, then use 'klick-its' think it's 3M that make them. That would get expensive for that spagetti mess you have there thou.
If you wrap them up in linerless rubber splicing tape (3M #130C), and keep the splice pointing up and near the top that works well too.
 

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Chief Flunky
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First question is why are you splicing in the handhole ? We put our spices in the Mast arm or Joint use pole ... that's what the door on them is for !

If you need a splice U/G or in a handhole/manhole, then use 'klick-its' think it's 3M that make them. That would get expensive for that spagetti mess you have there thou.
If you wrap them up in linerless rubber splicing tape (3M #130C), and keep the splice pointing up and near the top that works well too.
An extreme example is the City of Charleston, SC. They have very little space. All utility lines are underground. Their transformers and breakers, all underground in vaults. All the vaults are submerged in water all the time. Have been for decades. No problems at all. Think about that…the utility has their entire electrical distribution system buried in vaults and submerged under water, even the transformers and circuit breakers. Think about that the next time you step on a manhole walking around downtown Charleston.
 

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Open bottom ground boxes, which is what is in your picture, are supposed to be installed over stone at the very least. Stone with help in draining water. If in a water prone area water will always get in regardless. However there is supposed to be a good stone base, but more than not people dont do it. There are many ways to keep your connections dry.
 

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At plant waste water unit on the 480 motors in the tanks we used a connector cover that was full of a clear jelly that was reusable. I think Raychem made it that was for #2. The phone company uses a crimp on connector that has jelly in it. I don't know if they are available in building wire sizes. Then there are King wirenuts and I also have used tape and Scotchkote.

The Raychem product is GelCap and they available from #16 to 500MCM

LC
 

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I doubt you will ever have a 100% dry underground box,... period.

IMO, your 2nd picture is the best product for what you have.
 
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