Hi everyone, I have been greatly impressed by the quality and detail of the technical information given out freely on this forum, so much so that it has given me the confidence to sign up and hopefully help me sort out my dilemma.
Two years ago I purchased and fitted a Cyclotricity 250W brushless motor kit with a 36V 10Ahr pannier mounted battery to my partners bike. All went well until last October going up a hill the motor suddenly stopped. As it was getting towards the end of the season we left it in the shed until a couple of months ago when I started to try to get it working again. The problem is that when the main battery switch is put to the ON position the LCD display can be switched on but as after a couple of seconds pedalling the display goes blank and the motor stops. This can be repeated many times and each time the LCD display and motor cuts out. I have measured the battery voltage (B+ to B-) and also the voltage at the BMS (B+ to P-) during this operation. It seems that as soon as the battery starts to provide current to the motor, the voltage across B+ to P- drops to around 12V even though the voltage B+ to B- remains at around 39V. I have replaced the BMS with a new one from China and the fault is still the same.
What is the problem likely to be? If it is one of the battery cells am I best to buy a new battery (at around £300) which I do not want to do or buy one from Hobby King with a suitable charger at lower cost. Should I try running the kit with the BMS removed to see if the battery is faulty?
Many thanks in anticipation.
.
Two years ago I purchased and fitted a Cyclotricity 250W brushless motor kit with a 36V 10Ahr pannier mounted battery to my partners bike. All went well until last October going up a hill the motor suddenly stopped. As it was getting towards the end of the season we left it in the shed until a couple of months ago when I started to try to get it working again. The problem is that when the main battery switch is put to the ON position the LCD display can be switched on but as after a couple of seconds pedalling the display goes blank and the motor stops. This can be repeated many times and each time the LCD display and motor cuts out. I have measured the battery voltage (B+ to B-) and also the voltage at the BMS (B+ to P-) during this operation. It seems that as soon as the battery starts to provide current to the motor, the voltage across B+ to P- drops to around 12V even though the voltage B+ to B- remains at around 39V. I have replaced the BMS with a new one from China and the fault is still the same.
What is the problem likely to be? If it is one of the battery cells am I best to buy a new battery (at around £300) which I do not want to do or buy one from Hobby King with a suitable charger at lower cost. Should I try running the kit with the BMS removed to see if the battery is faulty?
Many thanks in anticipation.
.
