The fact that there is enough current to melt the connector but not enough to pop the fuse in the IpH/IC power supply is very odd.
Those two connector parts are replaceable, if you know how to solder, and can be careful when soldering on the circuit board. The trick would be finding the parts. You're not going to get them out of Pentair. The board was put together elsewhere (probably China), so even Pentair wouldn't have access to them. You can try googling "eight conductor circuit board connector" and see what pops up. If you can find the male part, one that fits the part of the new board, you could probably strip and tin the existing wires and jam them into the connector. Each connector is slightly different how that works, but it's doable.
Frankly, before I bought a new controller, or even the replacement circuit board, I would remove the connector from the existing circuit board (unsolder it), then cut off the other connector from the wires, and solder the bare wires right to the board. You might need to solder a pin to the board, then solder the wire to the pin, using heat shrink tubing to insulate the wires from each other. You really have nothing to lose if you get it wrong.
Of course, I'm speaking as one who has that skill set and the tools to un-solder and solder on a circuit board. It's not difficult, but it's the kind of thing you have down the
second time you do it.
But, of course, before you attempt any of that, you have to first find what is causing the over-current problem. Since you already replaced the controller, along with the fact that there is probably not anything on that circuit board drawing that kind of current, I'm suspecting the motor in the IpH itself. It might also be the SWG, but I'd start with the motor. Which is why I gave you the troubleshooting tip of disconnecting the motor to see if the problem goes away. If the motor is binding up somehow, or the pump components are not working smoothly, that, I think, could cause overheating in the circuit that drives the motor.
I suppose the trouble is: you don't want to connect the new board while the current problem exists, and you can't test for the problem without connecting the board. Does the old connector work well enough to get the IpH back online? If not, then I'd try soldering those wires to the old board before replacing it with the new board. Then I would run the IpH controller with the SWG plugged in, but without the IpH pump plugged in, and observe what happens. If that doesn't overheat, then plug the motor in and then monitor the heat off that black wire. If it gets too hot to touch, then it's the pump motor (or something in the pump causing the motor to work too hard).
@ogdento, any ideas?