Motor Control - Allen-Bradley PowerFlex 70 Reference Manual

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If the value is "SAVE MOP Ref " when the drive power returns, the MOP
reference is reloaded with the value from the non-volatile memory. When the
bit is set to 0, the MOP reference defaults to zero when power is restored. The
MOP save reference parameter and the MOP rate parameter can be changed
while the drive is running.
Bit 1
0 = Reset MOP reference when STOP edge is asserted
1 = Don't reset MOP reference when STOP is asserted (default)
Important: The MOP reset only occurs on the stop edge and is not continuously
cleared because the stop is asserted (this is always processed when a
stop edge is seen, even if the drive is stopped). The reset only applies
to the stop edge and not when a fault is detected.
In order to change the MOP reference (increment or decrement) a given DPI
port must have the MOP mask asserted (and the logic mask asserted). In the case
of the terminal block, if the MOP increment or MOP decrement function is
assigned to a digital input, then the act of asserting either of those inputs will
cause the TB to try and gain ownership of the MOP inc/dec reference change.
Ownership of the MOP function can be obtained even if the MOP reference is
not being used to control the drive. If ownership is granted, the owner has the
right to inc/dec the MOP reference. Whether this reference is the active speed
reference for the drive is separately selected via TB reference select, or Ref A/B
select through DPI.
The MOP Frequency parameter is an output which shows the active value of the
MOP reference in Hz x 10.
MOP handling with Direction Mode
If the Direction Mode is configured for "Unipolar, " then the MOP decrement
will clamp at zero not allowing the user to generate a negative MOP reference
that is clamped off by the reference generation. When Direction Mode =
"Bipolar" the MOP reference will permit the decrement function to produce
negative values. If the drive is configured for Direction Mode = "Bipolar" and
then is changed to "Unipolar", the MOP reference will also be clamped at zero if
it was less than zero.
See Torque Performance Modes on page 201
Rockwell Automation Publication PFLEX-RM001H-EN-P - June 2013
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