Safety should have had its own sub-forum long ago.
In Gold mining, your mine site still has to be "federally safe" and has to be part of your mine plan before you are allowed even mine.
If you own a mine, or mining claim, you'll know what a mining plan is and how important the safety aspect of it is.
It's sad to see someone's hard labor and investment go up in smoke...
Don't rule out sabotage, that's a lot of income, making a "poor" government jealous.
None the less, for those that are safety aware, here's the wiring section of my mining plan in a few words:
-Build an auto-kill switch system.
-When it comes to wiring, ALWAYS your largest gauge wire.
-Anything with Bitcoin mining should be 14 gauge minimum over 15 feet but 12 gauge is most desirable in any application and any length.
-The longer the extensions, the more you pay on delivery fees and the harder/expensive it gets to find large gauge extensions.
-I buy mine from Zoro, they sell good quality, large gauge, long extensions; good for USA and Canada.
-Keep PSU wires separate or as far from each other as possible.
-Use white wires when possible since it doesn't attract heat like black does.
-Monitor cable heat by hand throughout the day, report unusual hot-spots.
-Make sure that if you have light coming in that it cannot cause hot-spots to wires or machines. (A Running Black PSU in the sun is ticking bomb)
-Use white foam cores to cover black areas from the sun if miners can become exposed to harmful sunlight.
-If PSU wires are too wimpy, buy larger ones, those should definitely be 16ga to begin with.
-Overpower PSU - Works less but costs a bit more, always at least 100W over maximum recommended, 150 is ideal, 200 is best, 250 is overkill.
-Overpowering PSU also reduces the overall power tension in the system since it works less for the same work.
-The best cooling is outside air because it's free and plenty but that may not work in areas where the outside temp is too high; IE: Florida
-Keep mine's temperature around 35 degrees; miners are their own dehumidifier, very dry conditions increase fire hazard too.
-Make sure your home's wiring is modern, meaning, newer than 1975 (Not 100% sure on the year). If not, get it modernized.
-Make sure there is someone that can keep an eye on your mine if you leave for extended periods of time and train/pay them.
-Stack machines no more than 3 high for 1U's and do not stack 3U's at all.
Just because it's "computer mining" still makes it, mining. Same offline rules apply here too, that is, shit's gonna break, your suppliers will screw you over, you're gonna swear a lot but you'll enjoy what you're doing. There is a little saying in the Gold mining world we tell rookies.
If you fail to plan, you plan to fail
I think your problem was a lack of an automatic kill-switch system. Another type of miner that arose from Gold mining are "the hacks"... guys that do everything right all the way but hacks the last mile and loses everything. #ToddHoffman (A disgrace to Gold Miners)
Well, I hope new miners will read this thread before getting into Bitcoin mining, lots of good electrical and general safety comments in this thread. Should be made a sticky in the Getting Started forum.