Hi Dean,
I’m very happy we could get the matter resolved. I’ve let others manage aspects of the business and haven’t put enough attention on the retail side of things in recent times.
Frankly the combination of parts that we supplied as a kit (to you and others) was rather on the extreme side with a controller that’s overly powerful for the motor and the small capacity (but high power) battery. Such a powerful controller has large capacitors that have huge current inrush which is difficult to manage in the BMS. Customers would always want the most powerful, and would generally be happy with it, but then others might not appreciate the aggressive power delivery, not to mention the fact that putting high power into a geared hub motor will cause increased wear or failure to the gears/clutch or even the motor structure if used at high power for long periods.
The BMS in the battery needs to be able to survive abuse such as being shorted so short circuit protection needs to be in place (batteries can be trashed if your controller fails and goes dead short, or maybe diy cabling gets shorted, or such like). Even with the pre charge function in the BMS (BMS does include pre charge function or else you can’t have an effective short circuit protection) you can still end up having a short circuit trip on startup, due to the very large capacitors (500A plus is normal), which didn’t get close to fully charged during the 0.25s pre charge cycle on startup. These false trips on startup are easy enough to resolve with a setting change in the smart BMS (not easy for customer to do), or using a smaller controller, or connecting the ALREADY POWERED ON BATTERY (not power on when connected) to the controller via a pre charge connector such as xt90 (not a solution but more a workaround until a proper solution is applied).