C.5.2 configuration word (pressure) bit map – Delta RMC101 User Manual

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RMC100 and RMCWin User Manual

C-62

Note:

This bit is only available on pressure-only and force-only control axes and not on auxiliary

pressure and force axes. You can still use absolute mode with auxiliary pressure and force axes,
but the Absolute Mode bit of the position axis is used.
When this bit is set on a pressure-only or force-only axis, the drive output is limited between 0
and 10 volts. Therefore, if the drive would have gone negative it will be set to zero and the
integrator will be cleared to avoid integrator windup. This is used in situations where either the
pressure input is controlled by the RMC but the output is constantly bleeding out, or in situations
where the RMC controls the output but the input is constant.

Bits 1 - 2 - Prescale Divisor bits
These bits are used to prescale (reduce the resolution of) the Counts. Use bits 1 and 2 as follows:

Counts

Bit

For example, if bit 1 is set, but bit 2 is cleared, then the transducer counts will be divided by two
before being processed. It is more desirable to use these bits to apply the same divide-by on the
Scale factor; round off errors are minimized with the divide-by bits.

For example, suppose we calculate that our scale should be 2015.87, but because all parameters
must be integers, we enter 2016. We have an error of 0.01%. However we could use a Prescale
Divisor of 8 and a Scale of 16127 to give us an effective scale of 16127/8 or 2015.875. The error
on our scale is reduced to 0.0002%.

Notice that for differential analog axes, this pre-scale divisor affects both Counts A and B.

Bit 0 - Integrator Limit
When this bit is cleared, the integrator limit is 20% of the maximum drive output. When the bit is
set, the limit is 80%. If the integrator tries to go above the limit, the Integrator Windup bit in the
Status word is set and the integrator value is held at the limit. The integrator limit is designed to
prevent the drive output from saturating. This bit does not take affect until the axis is regulating
the pressure because the integrator is not active while in position mode.

C.5.2 Configuration Word (Pressure) Bit Map

The axis Configuration word contains 16 bits of information. The hexadecimal table below
provides an easy way to convert hexadecimal numbers to bit patterns.

This manual is related to the following products:

RMC100