Anyone familiar with electrics ?

[ufkacbln]

I have a cargo trilke with a Bafang Fun 8 motor

The battery is fully charged and showing all the correct lights

However when I apply the motor, it shows low battery, The motor then cuts out and the lights are restored to full battery mode. All connections have been checked and the contacts are secure and clean

I assume that this is caused by the load on the motor, so I have checked that all the wheels are running smoothly, there is no problem or resistance when pedaling so I can only assume this is a fault with the motor or circuitry

Returning this to the shop in London for checking is labourious, can anyone suggest what is causing this

 

[Stevec047]

What type of motor is it. If it has brushes inside next to the armature and they have a larger amount of carbon buildup this can cause excessive heat and poor performance. If it's brushless then I would say that there is a wiring issue. Best to trace the cables from the battery pack through to the speed controller and then on to the motor. Check for any pinched cables shorting against anything metal.

If this fails chances are it will be a sealed component issue such as the speed controller circuit.

I have a knowledge of electrics not from a cycling background but the same principles apply.

 

[ufkacbln]

Thanks
The motor seems to work OK as when it functions the power and drive are fine

There are no problems with either the wires or contacts

Your answer does however illustrate my problem

An overheating motor would cause both battery and motor issues and explain the cutting out

However the motor works almost immediately after cutting out

I had considered overheating, but the temperature feels no different to my wife's Bionx so I had excluded this

Taking a massive Cargo trike back to London is a hassle

I am hoping to send wheel and battery for them to test on a similar standard setup and diagnose that way

 

[Smurfy]

How old is the battery? Some battery types and methods of battery monitoring will show a healthy battery that dies as soon as you try and use it. Remove the load and the battery apparently recovers.

 

[Tim Hall]

Following on from @Smurfy , can you get hold of a volt meter? Measure the battery voltage on and off load. If voltage dives down under load that would suggest the battery is banjaxed.