Delta MMC120 - Manual (Page 117)

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Range: 0 to 65535
Same as EXTEND FEED FORWARD , except it is used when retracting.
NOTE:Retracting is the direction that returns decreasing TRANSDUCER COUNTS .
EXTEND ACCELERATION FEED FORWARD
Default: 0
Range: 0 to 65535
The Extend Acceleration Feed Forward causes the controller to give extra drive while
accelerating and a breaking drive while decelerating (negative acceleration) in the extend
direction. The drive due to Acceleration Feed Forward is calculated as follows:
Accel FF Drive = EXT ACCEL FF x 1 mV / 100,000 position units/sec/sec
The Acceleration Feed Forward provides a second order approximation ( prediction ) of
how much drive is required to move.
If the position unit is 0.001 inches, this equals millivolts of drive per 100 inches per
second per second.
Why Bother?
The acceleration feed forward help the axis track better while accelerating or decelerating
only. The acceleration feed forwards should not be adjusted until the velocity feed
forwards are adjusted correctly.
RETRACT ACCELERATION FEED FORWARD
Default: 0
Range: 0 to 65535
Same as EXTEND ACCELERATION FEED FORWARD , except it is used when
retracting.
DEAD BAND ELIMINATOR
Default: 0
Range: 0 to 2000
Some valves and drives do not react to small changes in output around the null drive
value; this effect is termed "dead band". The DEAD BAND ELIMINATOR value is the