Author Topic: Motor “cogging" when it starts to turn  (Read 4662 times)

Offline MickMick

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Motor “cogging" when it starts to turn
« on: March 06, 2018, 08:51:41 PM »
Hi all. I have just installed my new 10kw with vec500 in my motorbike. I had to re-work the motor wires and hall wires to get it to run in the right direction based on a post in this forum. The problem I have is that I am getting “cogging” when the motor starts to turn. Once you give it some gas, its off but the speed control could do with being better. My question is, is the new hall wiring config causing the cogging? If so, how do I fix it?

Offline Bikemad

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Re: Motor “cogging" when it starts to turn
« Reply #1 on: March 06, 2018, 11:04:15 PM »
Hi MickMick andto the forum.

If the motor is performing correctly, and not drawing excessive current at low throttle, then the Hall sensor/phase wire configuration is probably correct.

I don't know what is causing the cogging, but it might be worth raising/reducing the "start phase current (A)" to see if the cogging improves or worsens.

What overall gear ratio are you currently using?

Alan
 

Offline MickMick

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Re: Motor “cogging" when it starts to turn
« Reply #2 on: March 07, 2018, 11:36:07 PM »
Cheers Alan. I will give it a try.  :)

Offline MickMick

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Re: Motor “cogging" when it starts to turn
« Reply #3 on: March 08, 2018, 04:35:42 PM »
Hi, The default is only set at 15amps. Tried 25 and 50amps but still the same. It just seams to be the 1st and 2nd 120deg it struggles with. Wheels up, it is fine as expected. Is ther just not enough torque in the motor? I am running 11t front sprocket to 33t rear so. 1 to 3 ratio. Once it is past that initial two clunks, its off like a scolded cat. Pulls up to 40mph+ Still pulling(not test full speed until I get this sorted). Any thoughts?

Offline MickMick

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Re: Motor “cogging" when it starts to turn
« Reply #4 on: March 09, 2018, 12:22:40 PM »
What are valid values to the startup current? Up to battery current?

Offline Bikemad

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Re: Motor “cogging" when it starts to turn
« Reply #5 on: March 12, 2018, 11:17:45 AM »
I don't know what maximum values the controller will accept, but he maximum "start phase current (A)" should be set ~30% higher than the maximum battery current.

The maximum battery current setting should not exceed the maximum current that your particular battery can supply (its burst current, not continuous current).

For example, if the maximum battery current is set at 100A, the maximum start phase current should be set at 130A.

Alan
 

Offline MickMick

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Re: Motor “cogging" when it starts to turn
« Reply #6 on: March 13, 2018, 07:48:38 AM »
 Cheers. I will try a higher value. Odd that the default is only 15amps startup on a 200+ controller. My batter will do 450amps but I wont go that far. Will try 100 to 200 to see if it has any effect.