Looking for advice on proper weather proofing of outdoor junction box

Access

We have an outdoor electric junction box for the electric gates mounted on one of the driveway pillars same as below...



During the bad cold spell... the gates gave up working and on inspecting the same control box, i opened it to be greeted by that same scene in Indiana Jones where all the spiders and creepy crawlies come tumbling out towards poor old Indy! On inspecting the PCB after cleaning out the box, the board was damp with condensation as well as the back wall of the box itself.

after cleaning down the board with IPA and drying it off, i plugged it into to find all is working okay. So happy days there, as i had thought the board would have been shorted out by the crawlies!

My plan now is to buy a larger IP56 Gewiss box to place this box into... A box in a box for double protection.

creating an extra layer of protection. I would have the gate control box sealed properly within the sealed gewiss box... unneeded holes mastic sealed etc. I have also given the backside and front side of the gate control PCB a few coats of PCB lacquer sealer spray to further protect it

The advice im looking for is on how i could improve the crawlie/weather proofing of the boxes. I have seen advice online of people putting 7 watt small bulbs like that of christmas lights on a micro thermostat to kick in during freezing temps to slightly warm the control box, but surly wouldn't the transformer inside the gate control box give off enough heat to do the same thing?

Also, is it worth giving a light coat of WD40 spray to the interior of the same box? or even putting in a couple of those moisture absorbing desiccant Silica Gel bags?

Any ideas on how to give this setup an extra bit of protection are welcome... as im just about at the stage of reassembling the control box this weekend.

cast_iron

I think you seem to have most things covered pretty well at this stage. As long as all unused holes are selaed in the outer box there shouldn't be a problem. The panel probably has a temperature range it will operate in - considering we've had -18 celcius in some parts in the cold snap, it might be worth checking to see what that range is.

A 1mm or 2mm hole at the bottom of each box is advisable in case water gets in somehow and fills the boxes.

Access

Rated for -20 to +50C... We came close to the lower here!

The outer box will be new, so no problem with water getting in... i would also be reluctant to drill any sort of drainage holes as we have - as stated earlier - a serious problem with wood lice and ear wigs here during the winter months!

any other tips?

freddyuk

You can buy liquid electrical insulation. I got mine in the USA from the boat store but it is available here. Very good for tv and satellite connections as you paint it on with a brush and it seals all the cable connections preventing moisture ingress (or anything else) which is a requirement in West Cork.:)

cast_iron

With a box within a box setup that you are planning, I think you are more than covered.
That setup should also help with heat retention in extremely cold weather. I would agree the traffo should provide enough heat to keep things alive/dry in a cold snap.
Thinking about it, you would only need a 1mm hole in the outer box to avoid a water issue, and its small size would limit the amount of bugs getting in. With the inner box sealed, they wouldn't cause a problem anyway.

I only suggest the hole as I've opened countless "sealed boxes" that have drownded me due to a build up of water. The problem is usually that the seal seizes and shrivels away with time and the water barrier is then broken.

DI Dwyer

A propperly specified box which has been propperly installed should not allow ingress of any foreign bodies or water.... no holes needed! bad practice.... get on to the manufacturer of the gate control system and explain the problem you experienced.... no point talking to the installer, they are only agents for the manufacturer and are only interested in the sale aspect not the service.... annalogy... would it be acceptable to have foreign bodies and water entering all the motor JBs and terminal boxes you find outdoors in industry..

paddy147

freddyuk wrote: »

You can buy liquid electrical insulation. I got mine in the USA from the boat store but it is available here. Very good for tv and satellite connections as you paint it on with a brush and it seals all the cable connections preventing moisture ingress (or anything else) which is a requirement in West Cork.:)

Cabn you tell me where in Ireland I can get this liquid insulation please?

Thanks.:)

Access

Thanks to all so far for the info. much appreciated! Think ive got it sorted now, as all is up and running again.

fred funk }{

You could use a heater from a CCTV camera housing. This would keep the box condensation free.

http://cgi.ebay.ie/12-Volt-Heater-Thermostat-CCTV-camera-enclosure-/290482503201?pt=UK_CCTV&hash=item43a21b3e21#ht_2022wt_897