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Anything inherently wrong with installing consumer units outside?
IP rated (IP65/66).
The plan is to install henley blocks into the exterior meter cupboard, and a supply taken to an IP rated lockable enclosure on the wall directly below the cupboard to supply an outbuilding.
How does the sway in temperature impact MCB and RCD functionality? They all seem to be rated to sub zero temperatures and in excess of 40 degrees.
Its very clear units are IP66 rated so completely dust tight and protection against jets of water, so please explain how you drilling “ one or two holes” in the bottom of the back box would keep that manufacturers rating?
Its very clear units are IP66 rated so completely dust tight and protection against jets of water, so please explain how you drilling “ one or two holes” in the bottom of the back box would keep that manufacturers rating?
GTB
Nothing is totally water proof forever, eventually everything leaks.
Page 11 of the technical guide for the products. A drain hole position is provided and instructions provided for use. Just do not spray your jets in the hole and all is fine. I would add you would have to be going to an awful lot of trouble to spray water up through a drain hole.
ETA: Dusty environment, on the other hand, if excessive, may preclude a hole being drilled.
As the instructions say, the aim is to allow condensation to escape. I have always wondered how it gets in there if the conduit is intact and open only under shelter.
Always make a small drain hole at the lowest point. It allows natural aspiration and prevents condensation buildup. I try to use the bottom entry knockouts only. This is Chris's suggestion….
Especially for outdoor installations, making a drain hole even 1 mm wide just lets insects in, or, in places exposed to wind, a lot of dust and detritus which, even in areas not by the coast, causes corrosion and early failure of equipment.
I've seen the results in many installations.
The recommended approach is an IP55 drain plug (sometimes known as a “breather vent” or “vent drain”).
Where enclosures require natural ventilation for cooling or to prevent accumulation of battery gas, one is fitted one side of the enclosure at the bottom or lower side, and another (with appropriate baffle or “periscope”) on the top or upper, at the opposite side.
Page 11 of the technical guide for the products. A drain hole position is provided and instructions provided for use. Just do not spray your jets in the hole and all is fine. I would add you would have to be going to an awful lot of trouble to spray water up through a drain hole.
ETA: Dusty environment, on the other hand, if excessive, may preclude a hole being drilled.
Agreed - see my previous post regarding not only spray, but dust and insects.
Its very clear units are IP66 rated so completely dust tight and protection against jets of water, so please explain how you drilling “ one or two holes” in the bottom of the back box would keep that manufacturers rating?
GTB
Interestingly, IP66 is not guaranteed to provide protection against jets … well, it does the jet itself, but not always the side-effects on equipment inside the enclosure.
Please indulge me a moment.
Under certain conditions (such as jet washing, or where equipment is installed within 150-250 mm of the ground in a direct ground-mounted enclosure) where there is a sudden change in pressure or temperature outside the enclosure, condensation can form quickly inside the enclosure, or permit vapour ingress through seals. The only solutions are anti-condensation heating and muti-baffled “snail” vents with appropriate filtering or mesh (the best that achieves of course is IP65 with appropriate filters).
So, if equipment is installed in places that may be subject to jet washing, or within 150 mm of the ground, worth considering.
gkenyon: The recommended approach is an IP55 drain plug (sometimes known as a “breather vent” or “vent drain”).
I need to install a 30 m length of steel conduit which will run partly outdoors. Does it need drainage holes? If I just drilled at the lowest point, I am concerned that any burr inside the pipe would damage the cables.
I wonder whether it would be wise to use one of these vents at the first and last BESA boxes before the run goes outdoors?
Thanks for the instructions on the MK Masterseal unit, but read the wording carefully (Note 3) the drilling of the drain hole (5mm) is ONLY when you have conduit entering from the top or side entries. So conduit from the bottom, or any type of cable gland entry the Note 3 does not apply. Reason being the conduit is a hollow tube and condensation forming on the inside of the conduit will then of course run and settle within the enclosure body. A competant electrical installer would IMHO design the installation to prevent that happening, and something I was taught as a 16yr old apprentice, any outdoor enclosures entries should always as far as practicable enter from the bottom elevation as water cant run “Up” a cable or conduit.
IP66 as I have mentioned before is dust tight, i.e dust cant enter, so with the definition of dust as “finely divided solid particles, 500 μm or less in nominal size, which may be suspended in air, may settle out of the atmosphere under their own weight” then I doubt your small drilled hole 3 or 4mm would prevent dust entering, if you have conductive dust then that starts all sorts of other issues when it settles over a period of time on the insulating surfaces/contacts within the enclosure.
AS G Kenyon has said the best way is to use a breather plug and they are readily availible in diffrent sizes/threads and materials, just stick one of them in a bottom 20mm entry and away you go. link below to some Ex cert ones but you can buy non cert.
Many Industrial enclosure manufacturers also have darin plugs as optional accessories.
