CCS controller replaced; voltages seem off

[BeefEngineer]

I have a CCS, a bit more than a year and 3000 miles old. The bike motor had a bunch of issues starting about six months ago. After a lot of back-and-forth, Juiced eventually ended up replacing the rear wheel + motor and the electrical controller under warranty. The controller replacement probably wasn't necessary, but Juiced wanted to be thorough since they didn't know exactly what the problem was; can't complain about that strategy.

The new controller, however, doesn't seem to be tuned quite right. It's not a big deal, but it does affect QOL a bit, especially with range anxiety.

Specifically:
With the new controller, the (48V) battery voltage caps out at about 53.5 V, rather than 54.6 V. This wasn't a gradual degradation with battery aging/cycling; it coincided exactly with the controller replacement (I didn't notice it immediately because the battery wasn't fully charged when the repair was done). The discharge curve is affected as you'd expect - the display pips of remaining battery capacity drop much more quickly than before, though there is a lot more juice left in the battery at the low end, since the battery itself hasn't really changed.

Any ideas on how to check/fix this issue? I don't personally own a multimeter, though I know I need to get one. Could an e-bike shop fix this?

 

[michael mitchell]

What did Juiced say when you asked them about it?

 

[ctbaz]

My CCX is always showing 1V less than what the battery actually has as well.

 

[harryS]

You need to personally own a multimeter. The voltage readout on many displays is often not calibrated right. It shouldn't be, as it only costs anout 25 cents more in parts to do it right, but it is what it is

 

[BeefEngineer]

Haven't talked to Juiced about it; since I'm now out of warranty I didn't envision an easy solution from them, but I suppose I should at least give them a shot. I suppose it's good to know it's not only my bike with this issue.

 

[KLee]

My CCX is always showing 1V less than what the battery actually has as well.

My CCX shows 0.8 volts less that what my multi meter has.

 

[BeefEngineer]

Sounds like I just happened to go from one of the well-calibrated controllers to poorly calibrated one. Not the most debilitating condition, I suppose; maybe I just need to get to know this controller better and understand what the battery's true state is (while keeping the cutoff voltage low enough not to impede performance). Yes, I do plan to get a multimeter when I find one on sale.

 

[harryS]

I don't know whether the display's voltage reading matters to the operation of the bike. The motor will respond to the actual battery voltage, not to what the display says it is. And if you don't run the battery til the controller winks off, you will be doing it a favor for longevity by being easy on it. so any question of whether this affects LVC is moot.

 

[BeefEngineer]

I don't know whether the display's voltage reading matters to the operation of the bike. The motor will respond to the actual battery voltage, not to what the display says it is. And if you don't run the battery til the controller winks off, you will be doing it a favor for longevity by being easy on it. so any question of whether this affects LVC is moot.

The display didn't change, the electronic controller did. Power from the battery is routed through the controller before reaching the motor, and the controller draws the amperage necessary to reach the watts powering the motor. Since (I think) it's not reading the voltage correctly, it'll cut off the power prematurely if the LVC is set at the same level it should be set for a controller that's not reading 1 V too low. Nevertheless, I agree with your point that it would be good for battery longevity, just not for range anxiety.

 

[harryS]

@BeefEngineer, You changed the controller and not the display? I guess I read it wrong. My fault for not understanding.

There might be a short circuit protection device on the power line to the display that makes it read a bit low. None of my KT-LCD3 displays are accurate. I can turn them on while charging the battery and at full charge, they're off by ,2 to .4 volts.