KT Controller Mosfets

[Augoosteen]

Hello, does anyone know how a kt controller lowers it's max amperage after it is lowered through the display? Does it drop mosfets to reach a lower current? I have a kt40a that cuts out when hot. It is a 12 mosfet controller. I am thinking about installing a 18 mosfet 50a but setting the current down to 40a. I'm hoping all mosfets are still working at that amperage so that the 40a being drawn are not overloading it and causing failure. Thanks.

 

[Augoosteen]

Hello, does anyone know how a kt controller lowers it's max amperage after it is lowered through the display? Does it drop mosfets to reach a lower current? I have a kt40a that cuts out when hot. It is a 12 mosfet controller. I am thinking about installing a 18 mosfet 50a but setting the current down to 40a. I'm hoping all mosfets are still working at that amperage so that the 40a being drawn are not overloading it and causing failure. Thanks.

And I want to add that It only uses 40a under hard acceleration.

 

[calab]

Where do you place the controller, does it get air for cooling?

 

[Slowchris11]

12 MOSfet's are plenty. If you want more power, first look at the board for temperature sensor, near the fet's. Maybe simply screwing on some aluminum as additional heatsink may solve your problem.
Wrapping the controller into bubble wrap and dumping it in a bag is shock proof, but not temperature wise.

If you want to add Fet's for more amps, ie stronger ones, you have to use the same type and make, or the weakest in line will fail first. Usually is a swap of all the only way. Some controller measure the current through a shunt, in this case stronger fet's will not help.
You should be able to basically re-engineer the cirquit, otherwise you may only waste time and money. Never saw a schematic of a cheap controller, I guess schematics are forbidden by law in China. Any time I asked it was "Sorry, no, it's a company secret".
Better buy a stronger version of your controller and sell the old one.