upgrading to 48v
Posted by aero_sock@reddit | ebikes | View on Reddit | 6 comments
I have a bbs01 with this either 350 or 500w controller for 36v
im looking to upgrade to higher voltage for more power and maybe higher cadence, and I'm a little confused
I read some older posts that apparently the 36v controllers can also work with 48v, and the only limiting factor is the soft lock that can be bypassed with some custom software
so I was wondering if there are any people here who have done that, or if they instead chose the straightforward route of upgrading to a regular 48v bbs02 controller
aero_sock@reddit (OP)
update
according to guys on endless sphere forum, the components in the controller are rated to upto 63v, and the only limiting factor is the voltage in the controller firmware, not the controller hardware
apparently the only thing required to make your 36v bafang controller work, is to fool the display into thinking the battery voltage is below 44.8 volts.
there are many ways to do it, I went with a tvs diode with a breakdown voltage of 15v, P6KE15CA
the problem is that it gets very hot, even with those copper legs I soldered on for cooling, you can't touch the diode without burning your fingers, it's up there in 100c+
it works, and it successfully lowers the voltage and fools the display, but not ideal. I went ahead and ordered 1N5352B zener diode, which should fit better. Will report back how it goes.
as it relates to performance, I left the controller at 20a, and the power output and torque has been upped significantly. after about 10 15 minutes of hammering it, averaging at about 15a average consumption, the hottest part of the case, where the stator is, was probably at around 45 degrees at 10c ambient.
guess gotta be careful in the summer, might lower the limit to 18a then, we'll see
Adorable_Isopod3437@reddit
Why you want to do that? I do not recommend, will fail prematurely by overheating.
aero_sock@reddit (OP)
im going to keep the amperage below 20a. only changing the voltage. and as we all know P=I\^2*R
Adorable_Isopod3437@reddit
In my experience that you mean don't happens,aybe in paper, i do several mods like this weekly, i will do your math in thermal terms, if i have 48V at 20A max i got 960W of power/heat, in a casing made for dissipate 36V at 20A Max 720W, more than 30% of overpower. But try and let us know how much last.
aero_sock@reddit (OP)
oh yeah, I guess you are right.... well, I'll monitor the temperature and tweak it as we go
aero_sock@reddit (OP)
https://www.reddit.com/r/ebikes/s/KmLbkSZYMJ
referring to these comments here