Hi guys, I believe that my KT controller gave up the ghost today, but I do not know why or what exactly happened. Maybe you can help.
First, the details: I have a 20" bike, running on 16s A123 (~50V), with a Heinzmann motor (rather large direct drive).
Gallery:
https://imgur.com/a/tTuFe
I have this controller:
http://www.groetech.de/index.php?main_page=product_info&products_id=849
With an LCD5 display. I modified the controller by installing IRFB4110 Fets and 100V low-ESR brand-name caps.
I programmed the maximum current to 5A. The system has worked perfectly since april, for about 1.900km. 2 or 3 weeks ago, I enabled regen braking at the highest setting. This also worked well until today.
At first, the speed displayed at the LCD froze at ~11kph, and the batter charge indicator graph at the top was blank. Everything else still worked. I could choose different power stages, and the total voltage was also displayed correctly at the bottom.
The motor worked, and the speed limit as well. Power cycling both the LCD and the controller had no offect. After power cycling, the speed display was stuck at 0kph. About 1km farther I tried another power cycle on the controller, but this time, the motor did not work any more. Another power cycle on the LCD, and the motor jerked once slightly, but still didn't work afterwards. I wanted to cycle home (thankfully not that far) but noticed that the motor was difficult to spin. I remembered that this happens when the phases are shorted. So I unplugged one of the three phase cable connectors, and now the motor spun freely.
I am totally at a loss why these problems happened. The phase cable thing at last points to shorted phases, this can only happen via the FETs. But this seems totally unrelated to the malfunctioning LCD. Can a general malfunction somehow destroy the FETs? Can the regen braking have something to do with it? Is this function known to fry controllers? I wonder why it worked flawless at daily use during all summer, and just 2-3 weeks after enabling regen things fail...
Thanks for your help in advance,
Julian
First, the details: I have a 20" bike, running on 16s A123 (~50V), with a Heinzmann motor (rather large direct drive).
Gallery:
https://imgur.com/a/tTuFe
I have this controller:
http://www.groetech.de/index.php?main_page=product_info&products_id=849
With an LCD5 display. I modified the controller by installing IRFB4110 Fets and 100V low-ESR brand-name caps.
I programmed the maximum current to 5A. The system has worked perfectly since april, for about 1.900km. 2 or 3 weeks ago, I enabled regen braking at the highest setting. This also worked well until today.
At first, the speed displayed at the LCD froze at ~11kph, and the batter charge indicator graph at the top was blank. Everything else still worked. I could choose different power stages, and the total voltage was also displayed correctly at the bottom.
The motor worked, and the speed limit as well. Power cycling both the LCD and the controller had no offect. After power cycling, the speed display was stuck at 0kph. About 1km farther I tried another power cycle on the controller, but this time, the motor did not work any more. Another power cycle on the LCD, and the motor jerked once slightly, but still didn't work afterwards. I wanted to cycle home (thankfully not that far) but noticed that the motor was difficult to spin. I remembered that this happens when the phases are shorted. So I unplugged one of the three phase cable connectors, and now the motor spun freely.
I am totally at a loss why these problems happened. The phase cable thing at last points to shorted phases, this can only happen via the FETs. But this seems totally unrelated to the malfunctioning LCD. Can a general malfunction somehow destroy the FETs? Can the regen braking have something to do with it? Is this function known to fry controllers? I wonder why it worked flawless at daily use during all summer, and just 2-3 weeks after enabling regen things fail...
Thanks for your help in advance,
Julian