Looks to me like you could replace everything on that board with a single Mouser order for about $10. But I wouldn’t discount the thought that something downstream of this board could be the issue.
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This was my reason for asking the question about what it powered 
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Tanner has thermal breakers in many denominations, they reset in about 3 minutes
modification for the sake of solution…?
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Start simple. Check the rectifier diodes first. Those are a common failure point if a power surge occurs.
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Another simple test if it is blowing fuses is grab a thermal camera and short out the fuse holder. Pulse on and off power to it and see what’s way hotter than everything else. Odds are that your shorted component.
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Because of the shape of the machine, when
The board is installed, it’s very difficult to view
or easily access the fuse clips, so we didn’t
try to determine the speed that the fuse
failed after power up.
I’ve done a variant of that idea going way back
except i used fingertips, and yes, occasionally
Wished there was a thermal camera nearby.
Have you considered the problem may not be on this board? It is possible the motor itself is causing fuses to blow. Put new fuse in, disconnect motor, turn on and try to operate. It obviously will not drive but then turn off again and check the fuse.
If popped, then problem probably is on the board. If fuse still good, the motor or something off the board is implicated.
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Another variant on that theme is to put a 20A fuse in, and power on. Watch for the smoke to come out of the bad component (safety goggles).
Seriously, if it’s popping fuses instantly, unplug the motor and check all the power components (diodes, big transistors, caps, transformer) with an OhmMeter. There’s a fused (dead shorted) component, somewhere.
Here is an old troubleshooting trick when dealing with fuses that blow. Carefully solder a piece of solder wire across the fuse holder. Excess current will safely melt the solder. Using solder wire is cheaper than burning out new fuses all the time.
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A fuse IS solder wire…
You can tell by looking at it, this board was designed by a rookie. No serious designer has used fuses in 20 years, it’s all thermal breakers since the 90s. Also, is that a Full Wave Rectifier circuit in discrete diodes? Someone call the Mouser Police. That thing has China written all over it.
Get am OhmMeter, check the big bits, there is something dead shorted.
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Guessing that the fuse is on the AC line upstream of everything.
Check the light blue component next to yellow rectangular cap(?).
It’s probably a surge protecting MOV.
It can take only so many hits before it fails - usually fails as a short - hence the need for a fuse upstream.
Check the diode near the motor connectors - probably a flyback diode. Protects ckt from back emf from the dc motor.
Also consider checking the brushes on the dc motor.
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I checked the power devices out with an Multi-Meter. Nothing was fried. We put a 1A fuse in the holder, fired-up the board, and got 171 VDC in the MosFET power supply, and the fuse survived.
I don’t think there is a problem with this board.
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Tom, this is still in the VECTOR area a year later. 
Do you still want someone to have a look, or have you found a replacement or substitute by now?
Maybe you should call the phone # in original post? Guy isn’t a member at present, so likely wont see your post.
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This is why i’m for a no-tolerance policy on personal storage in committee areas. This guy dropped off some literal garbage and isn’t even a member anymore.
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It’s not only a year later for the post, but a year later since BusyTom - who only ever participated in this topic - has been seen. Someone else can certainly call them if they’d like, but it doesn’t seem very important to them at this point.
We can always store it in Mount Carrollton.
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@mrcity - Relocate it to Lost and Found and let that process take care of it.
If it were important he would’ve followed up.
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They eliminated Lost & Found for time being.
I think that residing in a closet for a year has kind of already fulfilled the Logistics process. OP asked to be called before item was disposed of - if the committee chair chooses to do so, he can. But if not, I’d say “too bad, so sad.” and call it a day.