Controller advice please.

[aseb]

I have a Powabyke x-byke and am trying to get it sorted with a larger 20Ah battery. I have previously asked about the possibility of a higher powered motor but with help of the forum came to the conclusion that the existing one is best suited for my needs. I'd like to (belatedly) expand in a different direction- is it worth updating the controller bearing in mind the increased battery capacity?

From the earlier posts my current brush motor may produce up to 900W peak, and the voltage drop I see when climbing hills should be much reduced.

The LiFePO4 battery controller cuts power but I assume that this will be at a different level to the LiIon battery- and I gather that the controller fulfills this function for the LiIon batteries. How do these levels compare? A quick look at the controller figures show the cut off voltage varying by a few Volts so I guess some may be set up more for other battery technologies- where do NiMH and Lead fit in?

Thanks!

 

[NRG]

As Flecc points out here: http://www.pedelecs.co.uk/forum/electric-bicycles/7167-am-i-right-thinking.html different battery types have slightly different cell voltages so if you are relying on the controller for pack LVC then it may or may not be compatible with the pack you are using.

However, LVC on the controller does not provide LVC at the cell level IE: the overall pack voltage may be OK but there may be a weak cell in the middle of it that's not.....here the battery BMS will cut power to protect the weak cell so LVC may be hit earlier than you think....

I would happily recommend a new controller as the likes of the E-crazyman ones are programable for LVC and other parameters including speeds but you have a brushed motor and I don't think he makes controllers for them.

 

[theskip1]

As Flecc points out here: http://www.pedelecs.co.uk/forum/electric-bicycles/7167-am-i-right-thinking.html different battery types have slightly different cell voltages so if you are relying on the controller for pack LVC then it may or may not be compatible with the pack you are using.

However, LVC on the controller does not provide LVC at the cell level IE: the overall pack voltage may be OK but there may be a weak cell in the middle of it that's not.....here the battery BMS will cut power to protect the weak cell so LVC may be hit earlier than you think....

I would happily recommend a new controller as the likes of the E-crazyman ones are programable for LVC and other parameters including speeds but you have a brushed motor and I don't think he makes controllers for them.

yes he does make controlers for brushed motors, i bought one for my old powabike. but it is not programable because brushed motors do not have a power cut off. only the battery bms cuts the power.
theskip1

 

[aseb]

yes he does make controlers for brushed motors, i bought one for my old powabike. but it is not programable because brushed motors do not have a power cut off. only the battery bms cuts the power.
theskip1

I'll contact him to see what he has. I might look at the controller on the powabyke in case there are adjustable voltage points. It would be nice to have a circuit diagram but I doubt powabyke will be able to help, they seem to struggle a bit with any more involved technical questions.

 

[theskip1]

I'll contact him to see what he has. I might look at the controller on the powabyke in case there are adjustable voltage points. It would be nice to have a circuit diagram but I doubt powabyke will be able to help, they seem to struggle a bit with any more involved technical questions.

i have one as i say but it is pretty basic ,no ajustments that i can see, but at about £15, as opposed to powerbykes at more like £70-£80, well worth it i have had no probs in 6 months but be aware you lose the pedelec its throttle only.

 

[aseb]

i have one as i say but it is pretty basic ,no ajustments that i can see, but at about £15, as opposed to powerbykes at more like £70-£80, well worth it i have had no probs in 6 months but be aware you lose the pedelec its throttle only.

Which one did you get?
I'm struggling a bit deciding because specs that say 500W can have different fuse ratings (meaning different peak powers?) I've seen 25A (same as original), 30A and most just don't say- or maybe they aren't fused? Or the 500W is really the peak ouput?
I was considering a (~700W with 36V) 500-1000W YK43B YIYUN or 800W Shenzen Sucteam (max current 40A) but am wondering if they will be too much for the motor. The yiyun only has battery in, power out and throttle connections- only the basic ones needed and no low voltage protection. The shenzen has a bit more wiring- lock connection and brake cut-off, and low voltage protection of 30.5V. (My battery is 20Ah so 2C would be 40A so should be ok for the above).

Any comments from anyone? Would I be putting too much power to the motor?