A few years ago I decided to reduce the number of places I had 240V outside by replacing 240V ropelight and incandescent bulb items with cooler and greener 5v or 24V LED items. Because of the nature of the new-style display, I have actually increased the number of places 240V goes to because I have now mounted power supplies and controllers in boxes throughout the yard, but to ensure this is done safely I have spent time testing and trialling various boxes and sealing methods to ensure the best combination of waterproofing and heat extraction from the equipment.
It is almost impossible, with my small budget, to both have heat extraction and total waterproofing in the one cabinet, so I have chosen to not make my boxes waterproof, but rainproof. This means that when mounted in place in the yard any rainfall will not enter openings, through door seals or vents. If standing water (i.e flooding) gets to the level of the controllers then a few damp controllers will be the least of my worries.
What I want to avoid is placing power out in the yard where water can cause issues. 5v, 12v and 24V used in the display has no real problem with water, but 240v and water do not mix, but some people do not understand this at all. Putting it bluntly it can KILL, and has killed people in the past, and will in the future, and relying on an ELCB to protect you is beyond absurd. The 2 images below were sent to me by a neighbour and show a display only a few houses away, where they had 240v powerboards laying in the yard, uncovered while it rained, and this was left like that for the entire month of December.
Who says people know better than to mix power and water? Sigh! Don't be like this, please keep your 240v connections away from water.
I started with some used plastic boxes sourced from a local contractor, and then sealed any existing holes which I did not want to use with an initial filler of Araldite and then some UV stable Neutral Cure Silastic over the top. This gives a nice solid and waterproof seal for the holes, and because I use a paintable silastic, they can also later be painted to help disguise the boxes.
After sealing any new holes were cut or drilled in place, and waterproof cable glands used for the main cable entries and exits. All connections were done external to the cases so that there was no need to open them in the yard at all. Short 2 pin plugs were used for power to items, 3 core for DMX in and out, 4 core for connections to pixel, 5V LED strings as well as pDMX in and out, and 5 core used for the 5 wire house outlines. The 240V power leads were made long enough to reach the front deck in a single piece, meaning there is no need to have 240V connections in the yard.
Some of the cases:
Ventilation & Heat Removal
For some items, a box containing controllers and a power supply may not need ventilation if it is not a large power supply, or it is lightly loaded. Many normal setups in small cases do need some external venting to stop the case getting too hot, and shortening the life of the electronics and power supplies within.
The above image shows a case packed with a 5V 350W power supply and a PIXAD8 controller. The vent on the front is lined up with the output of the power supply fan inside, and the air inlet on the bottom also has a fine mesh plug inside it to stop bugs getting in and also minimise water entry.
The 90 degree bend on the outlet pipe allowed the heat to escape but stop rain from entering the pipe, no matter how hard it rained or blew. It might look a little agricultural, but it worked extremely well, even when hosed. Prior to installing the boxes in the yard a layer of Aluminium fly screen was cable-tied over the outlet air pipe to stop bugs crawling back inside the case through that opening.
Cable connection sealing
The 2, 3, 4 and 5 pin connectors purchased for the display here have a small o-ring and screw seal, and actually seal extremely effectively, and with over 150 of them in use in 2011, none showed signs of water ingress due to the rain. I did try and keep the connections out of standing water, and off the ground where possible.