DAC scale factor

DAC scale factor

As DAC is an axis parameter, it is a 32 bit signed number. What the range of values means depends on the drive. Some use RPM, so DAC_OUT value 1000 = 1000 RPM. Drives use a lot of different scale factors. Some might be 2^31 = 3000 RPM for example. The best way to refer to the max and minimum is to refer to the Drive's manual.

If you require to increase or limit the DAC scale use OUTLIMIT. The output limit restricts the DAC output to a lower value than the maximum. This can be used to limit the analogue outputs or demand value to a digital drive. OUTLIMIT will always limit the DAC output if you are using a servo control or just manually setting DAC. 

The value required varies depending on whether the axis has a 12 bit or 16 bit DAC.  If the voltage output is generated by a 12 bit DAC values an OUTLIMIT of 2047 will produce the full +/-10v range. If the voltage output is generated by a 16 bit DAC values an OUTLIMIT of 32767 will produce the full +/-10v range.

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