i have problem and maybe someone know how to solve it. i damaged two kt controllers, one 48v 22A and one 48v 45A 18fet. i build battery pack 15s, with max voltage of 61.5v. Since i use this pack with cheap no name china controller and work great, but i want switch to sine wave, and i upgraded motor. so i have 15s with max 61.5V, caps inside both controller are 63v. first controller worked for 30km, i connect it to battery when i have about 57v, then i charge baterry and after full charge (61,5V) controller is damaged, so i think it happends, and i buy new one with more fet (18fet) and do the same, i make about 50km with about 60-61V, everything was ok till i charge battery to 61.5V RIght now i have two controllers both damaged the same. it power up, communicate with lcd, everything seems working, but when you press throttle nothing happend, is show no error, but whell dont spin. But when you lift wheel and turn it backward, and it still turning slowly back and then press throttle everything work, it speeds up to max speed, when i press brake and give dummy load, it take 30A i can add and back throttle and its slows and speed , but if they motor slows too much, again i cant do nothing. when i stop and turn wheel again backwards and press throttle again it works. btw battery is still 61V.for sure motor is 100% works since i connect no name controller and it works flawless. what can be damaged ? iits looks like it dont wanna start, like missing one phase, or maybe controller dont see hall? but when i disconnect cable i get error about sensor position fault.
Right now i open controller and give throttle, nothing happend and i check voltage on phase wires on pcb, and blue and green have about 11.04V when i max throttle, but yellow one have 0.0V wheel dont spin. Then i spin whell backwards and its run then stop and measure again and now yellow wire respond to throttle giving 11v but other two phase wires now are 0.0v, when i spin wheel backwards again and repeat my test again yellow 0.0 other phases wire 11v.
Right now i open controller and give throttle, nothing happend and i check voltage on phase wires on pcb, and blue and green have about 11.04V when i max throttle, but yellow one have 0.0V wheel dont spin. Then i spin whell backwards and its run then stop and measure again and now yellow wire respond to throttle giving 11v but other two phase wires now are 0.0v, when i spin wheel backwards again and repeat my test again yellow 0.0 other phases wire 11v.