Throttle voltage low

[MarkLyons]

I have VEC500 controller on 10kw motor.
When I measure the output voltage for controller to throttle it is 5.4 volts without throttle plugged in. When I plug the throttle in it drops to 3.2 volts. Output from throttle only goes from 0.8 to 1.8 volts.
Not getting much power like that obviously.
Seems like an obvious throttle problem so can anyone recommend a good Hall effect throttle for a dirt bike. Cheers

[Bikemad]

Hi Mark,

The voltage drop might be caused by a faulty throttle, but it could also be due to a poor connection or a weak +5V supply coming from the controller.

Is it a Golden Motor (Wuxing) twist throttle that you are currently using, and has the output voltage recently changed?

Assuming your voltmeter is accurate, if you are able to set the Throttle minimum valid voltage (V) setting to 1.0V and the Throttle maximum valid voltage (V) setting to 1.8V the controller should be able to produce full power with your existing throttle:



However, it would obviously be better to try another throttle to determine whether the problem is within the throttle/wiring or the controller.

I have only ever used the supplied GM throttles on all my ebike conversions and I have never experienced a throttle problem over the last 12 years.

Alan
 

[MarkLyons]

Thank you
Was a bad connection on 5v supply to throttle
Another problem I have is throttle control when riding.
When accelerating bike pulls really well but there’s a delay coming off the throttle
I have the min voltage for throttle set to highest value of 1.5 volts which reduced this but its still there.
Also when accelerating at say half throttle, at about half max speed it feel like I’m giving it extra throttle when I’m not. Two different throttles behave the same also. Also different controllers with the same settings.
I’ve heard of having a potentiometer type throttle through a separate interface to hall sensor can improve this.
Appreciate any advice you can give cheers

[Bikemad]

Hi Mark,

Make sure that any altered parameters were saved correctly by reading the parameters from the controller again (Upload):



Often the parameters are not saved to the controller as expected due to the ambiguous icons. 

Did you also check the connection on the throttle ground wire as well as the +5V?

A poor ground connection on the throttle may cause the throttle to behave strangely.

Do you have anything connected to the lighting feed wire which is fed via the throttle switch? (E.g. a light, relay or contactor etc.)

Check out this post for details regarding a throttle problem that I previously experienced with a Smart Pie installation.

Alan