Outside light query

[newshound]

"Life will find a way".

[newshound]

I can see some circumstances where adding a "drain hole" might cause an enclosure to fail the IP "knitting needle" test. That said, my view is that anyone who tries to poke a knitting needle through a hole in an electrical enclosure probably deserves to be zapped. Which is why we are in philosophy territory: what constitutes "safe"?

[Vir Campestris]

The slug that crawled up the cable from our pond pump into the back of the breaker was _not_ alive after the power tripped.

Andy

[Johnny B Good]

Unless you can make the weather seals *gas-tight*, moisture will eventually accumulate inside such fittings. Silica-gel will only delay the inevitable unless you include a heating element to dry it out on a regular basis.

Aside from the issues of ingress by suicidal flora and fauna, it's often best to have as much ventilation as possible without compromising protection against horizontal driving precipitation. In some locations, this might be defeated by the more severe forms of precipitation which can be driven by up-draughts a considerable way towards any exposed connections taking shelter from the elements in such an 'open air' protective shroud.

One thing to consider, if adding a couple of 3 or 4 mm drain holes in something like a PIR controlled 300 or 500 watt halogen security floodlight, is the possibility of rainwater being rapidly sucked into the enclosure when the lamp switches off causing a rapid drop in temperature which generates a vacuum. The resulting spray could well impinge on the still hot lamp's envelope causing it to crack or shatter from the ensuing localised rapid cooling. Even something as apparently humble as a drain hole needs to be properly engineered if you wish to minimise interference by Murphy of "Murphy's Law" fame.

The modern world of manufacturing seems to be tackling the issue of Murphy's Law by, in effect, waving two fingers at Murphy and saying, "We can make them faster than you can break them!" Things can be designed to be proofed against Murphy's Law, it's known in the trade as "Over- Engineering", something not normally countenanced by the "Bean-Counters" so we rarely see such wonders in real life these days. :-(

[tabbypurr]

You're way overestimating things. There is no possibility of spraying.

NT

[Johnny B Good]

Shhh... Don't let "Murphy" hear you say things like that. :-)

[ARW]

That reminds me I have a new thread to make.

Bloody slugs.