Thread: Current Control
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Unread 20-06-2010, 18:22
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Re: Current Control

Quote:
Originally Posted by EricVanWyk View Post
Marshall -

Something in my head just jostled loose regarding this statement.

The PID loop uses the current sensor as an input and gives duty cycle as an output. Therefore, the style of analysis you were attempting does not work in this situation. Your example becomes:

% on time = scaling_factor * 1 * (40-2.5)

instead of

Amps = 1 * (40A-2.5A)
Did I mis-state something?.
The output I was recording was the voltage across the motor's leads, as reported by the Jaguar. (I have a Fluke 175 I could use instead if the Jaguars just report a calculated value for voltage)

What do you suppose the scaling factor could be? There is no configuration that relates to this, except perhaps "number of brushes".
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