IMO properly providing and monitoring clean power with overrated cable is the best way to prevent fires.
I run overclocked AntMiners at 200GH/s (400 MHz) with a 2nd 120mm high volume fan added as an exhaust off of Corsair RM 550W power supplies, the PSU and all power cables remain cool, miners run steadily at 38C (100F) in a room kept around 20C (68F) during winter and around 22C (72F) during summer.
Here is a shot of a external digital display thermometer monitoring 2 AntMiner S1s:
windpath -
Where did you get those temp displays? How much they run? Those are sweet!
One thought though - is that the modular 550W Corsair supply that has both PCI-E 6-pins off one cable? If so I would find a different way to wire it! (see my 8-pin mobo trick mentioned below)
My policy on ANTS is to have dedicated wires to each module. I ended up going with Corsair RM650 supplies ($40 refurbs off eBay) as I found the RM550 was only giving me 11.55V and I get 11.8V on all the 650s.
-----------------------------------------------
Good prevention list (even though I didn't quote it) -- Between a buddy and myself we have purchased 5TH of ANTMiner S1s and have a few other ideas to add:
1) Buy a Voltmeter. Check the voltage each PSU puts out every now and then. The first sign of a failing PSU is generally a voltage drop. Have a supply drop from 11.8V to 11.2? Take it out of service! I think 11.6 or 11.7V is the lowest "tested at the ant" voltage I feel comfortable with. My buddy runs a few with 11.5V just fine.
2) Buy a Killawatt meter. Check the draw from the wall. I had an old SilverStone 1KW supply I had mined for two years on with GPUs (very abused) before I re-purposed it for an ANTMiner. After two months I noticed the output air was warmer then I remembered. Because I had tested it before and knew it did @ 420W the wall I was shocked to see it now drawing 450W! The PSU was dead a week later...
3) DO THE CIRCUIT MATH! I wired in some extra 20A breakers and run 4-ANTS per line, but split off to two surge protectors/strips. So I know I am drawing ~1680W from the outlet (rated 2400W max), but only ~840W through each power strip. You don't want power strips getting warm and drawing over 1KW constantly on a standard 15A strip is just asking for trouble. Also a nice trick I learned if you aren't sure what circuits wire where - if you plug in a Killawatt meter and turn on a large load (ie vaccuum, toaster, etc) on the same circuit you will notice a voltage drop. I.E. I knew I was in trouble when I had 3 ANTS on a circuit and watched the volts drop from 118V to 115V when the wife plugged in a toaster on a rarely used outlet in the kitchen!
4) PSU Rails on multi-rail PSUs. How are they wired? Had another buddy fry a 1KW supply because he didn't realize it had 4 rails - two for all PCI-E conections, one for all molex/SATA, and one for motherboard. So it really was only a 500W supply on the PCI-E connections! A voltmeter and the voltage drop concept again can help "map" a PSU's rails even if the manufacturer doesn't list the config. Note you can also use a motherboard 8-pin as PCI-E 6-pin if you reverse the polarity and use the mobo rail/cable that is wasted on some supplies BUT test everything with the voltmeter for and KNOW WHAT YOU ARE DOING (ie at your own risk, YMMV, etc)!
4) Write everything down! Collect all the data mentioned above, then save it in a spreadsheet or a notebook. Then when you check on things in a couple weeks or a month you'll notice what changed and start seeing trends...
Other good tips:
Always have an extra PSU or two handy. N+1