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Unread 14-02-2016, 15:30
philso philso is offline
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Re: spark controller dropping voltage in reverse

Please confirm that you are using a DVM to measure the output of the motor controller. It seems from your post that you feel the output voltage of the motor controller should be larger.

Have you calibrated your motor controllers yet?

Do a quick check and substitute another SPARK and see if the result is the same. Substitute a PWM motor controller of a different type. If they all do the same thing (low output voltage), you should probably take a very close look at your software, going line by line. You will have to put aside what you THINK the software SHOULD be doing and look at what it really IS doing.

Through the magic of PWM, you should always get a voltage on the output of a DC motor controller that is between zero and your instantaneous battery voltage. The polarity will depend on whether you are commanding forward or reverse.