underground joints

[fulla]

hi guys
i have to connect 50 outside lights the wiring will be swa cable and a flex off to each light my idea was to make off the swa in to an adaptable box, bring the flex for the light in to the box joint cores in connector block and fill with cold pour resin. this job has been done before but because the boxes were buried over time they filled with condensation and caused problems hence the reason i will use resin.
the only trouble i see is that i will have to gland off over 100 ends and drill the boxes for earthing banjos
has anyone got a better idea

 

[GLENNSPARK]

scotchcasts.....dont need to banjo em......come with a "hepbond"....that you crimp onto the armourings using an inner sleave that goes over the inner serving of the armoured...and a split outer that you close up with a large crimper over the armourings (the hepbond goes between these 2)....that keeps the armourings continuous..... you can use waterpump pliers to close the outer ring with a bit of brawn behind em......plastic shell....and your 2 part resin,....clip on lid to finish.......very reliable joints these....

 

[Lighthouse Phil]

I'm looking up a name of a two part mix, it gets poured into your joint box. 100% water tight but will allow you to push a screwdriver in at a later date..........I'll be back...

 

[Lighthouse Phil]

Glenn beat me to it.....cant remember the name tho

 

[needasparks]

Is it Wiska pack, or something like that.

 

[johnboy6083]

Most smaller joints don't even need that now Glenn. You have roll springs, and braiding that you use to keep the armoured continuous. A splice joint would be suitable for what the OP wants.

 

[johnboy6083]

Dielectric gel AKA potting compound will also be good for this. I use this for sealing flow meters that are often submerged for years.
I can't remember who makes it.

 

[Lofty]

You could use Pratley ( Pratley Junction Boxes for Ex Applications ) boxes. They're designed for underground use, in fact pulled some up the other day that have been underground for 15 yrs+ and dry as a bone inside.

Cheers,
Lofty.

 

[johnboy6083]

This is the stuff. DOW CORNING® 3-4150 DIELECTRIC GEL KIT

 

[Engineer54]

Cast resin joints are fine to use, so long as you will never need to get at the joint again. If you do, then a compound filled wiska box, or other IP 68 box, is your best alternative. One type of box is expensive but no need to drill hole the other is a cheaper alternative where you will need to drill hole. ..The choice is yours, ...things are not always easy, and the easy choices are rarely the best solution either...

 

[mackers]

resin joint, like everyone else but wheres the flex running to, is that in the ground?

 

[Knobhead]

If your coming out of the joint with flex forget any hard setting compound. As sure as night follows day you’ll have to get back in to them again. Have a serious rethink on your plans.

 

[Deleted member 26818]

There's no need to drill the box for the banjos.
Put the banjo on the inside, bend the tag op and bolt the earth conductor to the tag.

 

[johnboy6083]

Or use pyranha earthing nuts!

 

[LineProducts]

Mackers raised an important issue. Tell us more about what you are doing I.e. Are you intending one swa and one flex per box, or two swa plus flex and how will you protect the flex? Etc

Is coming out of the ground with SWA and then changing to flex an option?

Also what is more important - saving labour or saving on material costs?

It will then be easier to recommend a product.

 

[Knobhead]

Good on you LP, if anyone can give an answer it's you.

 

[cakey]

Bring swa up into about 300mm of 4inch pipe so top of pipe is an inch above finished ground level. Terminate into suitable enclosure. Get 4 inch stop end/cover fitting for pipe. Bring flex up through cover fitting with stuffing gland. Fit cover to pipe. Flex into light fitting and screw fitting onto cover or spike into ground adjacent to it.

 

[Engineer54]

Bring swa up into about 300mm of 4inch pipe so top of pipe is an inch above finished ground level. Terminate into suitable enclosure. Get 4 inch stop end/cover fitting for pipe. Bring flex up through cover fitting with stuffing gland. Fit cover to pipe. Flex into light fitting and screw fitting onto cover or spike into ground adjacent to it.

That will stop condensation problems will it?? I think he'll be back where he started, in a very short space of time!! lol!!

 

[cakey]

That will stop condensation problems will it?? I think he'll be back where he started, in a very short space of time!! lol!!

If it's terminated into wiska box and it's not buried in dirt but sits inside pipe u think it will get condensation inside wiska box? Had this set up in my garden over 6 years and looked inside one couple of months back it was dry as a bone. Hole is drilled into side of cover to allow it to breathe.

Respect to the respected member.

 

[fulla]

thanks for all your comments, there will be swa cable in and out of box and the box will be located directly under the light, was going to use a trs flex to feed light. after looking at the wiska boxes already commented on they also make a double brass nut which fits inside the box and lines up with the holes it also has a terminal on it for the fitting of an earth conductor. has any one used this gel compound that wiska sell, have doubts about it because it says to can remove it.wonder if solid resin is the way to go

 

[Engineer54]

If it's terminated into wiska box and it's not buried in dirt but sits inside pipe u think it will get condensation inside wiska box? Had this set up in my garden over 6 years and looked inside one couple of months back it was dry as a bone. Hole is drilled into side of cover to allow it to breathe.

Respect to the respected member.

Physics tell us, that if you seal a pipe that is open to a damp soil, in times of changing temperatures, condensation to one level or another will occur in your wiska box!! Leave a mild steel washer in this wiska box of yours, for 6mth's. If it hasn't shown sign's of going rusty in that time you have beaten the common rules of condensation..

 

[Knobhead]

If you insist on burying the joint have a look for some braided butyl flex for the lamp feeds.
I hope your good at UG cable jointing because your going to get plenty of practice.

 

[Engineer54]

No-one seems to have mentioned ''Heat Shrink'' UG jointing method. Plenty of these about, they come in all different guise's, easy to make off and long lasting....