Nice one 'noneyabussiness'.
Good old 'Poida'.
Give it a go 'fabieville'. 'noneyabussiness' knows what he is talking about and achieved good results with your type of boards, but remember he has the 24 FET version.
The Power Board Mosfets.......
“In theory, a single 4110 can carry 150amps@100v... so a single one can actually do 15kw on it's own.
Practice is different, those skinny legs can't handle 100 amps continuous, apparently the silicon can, as it has a resistance of only .003 ohms.... so at 100 amps it will drop E=IR or 100x .003 or .3v losses@100amps.. so the dissipation will be W=ExI or 100 x .3... or only 30 watts.. so that leaves over 340 watts of dissipation spare.
Can you see that the dissipation figures are not the power handling figures, the 370w is the figure it can safely dissipate in losses..... not throughput. It's losses is the Rds on in ohms (.003-.006 for 4110) x the current flowing through it... these losses are dissipated in the mosfet and heat sink.
Switching losses are added to the IR losses, ( and in anything I build usually outweigh the resistive losses hands down). Getting the switching losses down is a science unto itself... black science almost, add in parasitic oscillations and lots of other gremlins, and we have our work cut out to keep the losses less than the 370 watts. If we fail, it goes up in smoke.
For the most part, if we keep the switching frequency low, stick to the design rules regarding layout etc etc etc... we do pretty darn well.
With 6 fets per leg, we get roughly 150X6=900 amps of capacity X the voltage we switch... 48X900=43000w or more.. my bank is usually 56v so 56X900=50kw. ( so it should easily survive transients of this level)
Now these figures are all theoretical, and have no real place in the real world... except for fractions of a second, and there they count.
We switch at high speed........ over 20 thousand times per second... so we don't need to carry these currents for long, and our duty cycle is less than 100% (each leg is turned on only at a max of 40% of the time I suspect).
So in fractional times, 60kw is not out of the question... and surviving it is possible too. Remember of your 24 fets, you can only calculate for 6, as each leg only has 6fets..... not 24.
I use the 15kw boards because the fet spacing is greater, and so cooling is better..... mostly not of interest, but more surface is always better than less.
...........oztules