Delta MMC120 - Manual (Page 36)

Motion Control Parameters MMC120 Linear Motion Control Module
36 Delta Computer Systems, Inc. 360/254-8688
Bits 15 and 16 - Acceleration and Deceleration MODE Select
These two bits define four acceleration/deceleration modes:
Bit #
15 16
Mode 0 - Ramp Rate (Default) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 0 0
Mode 1 - Ramp Rate * 1000 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 0 1
Mode 2 - Distance to specified speed - - - - - - - - - - - - - - - - - - - - - - - - - - 1 0
Mode 3 - Time to specified speed - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1 1
In Mode 0, the ACCELERATION and DECELERATION parameters define the ramp rate in position units
per second per second.
In Mode 1, the ACCELERATION and DECELERATION parameters define the ramp rate in 1000 position
units per second per second. For example, with position units of 0.001 inches, an ACCELERATION of 50
will cause the axis to accelerate at 50 inches per second per second.
In Mode 2, the parameters define the distance to accelerate or decelerate to the specified SPEED.
In Mode 3, the parameters define the time to accelerate or decelerate to the specified SPEED.
ACCELERATION (Default: 1000)
This parameter defines the acceleration ramp rate used by the axis for a move. It has four meanings
depending on the setting of the acceleration/deceleration mode.
In Mode 0, this parameter is interpreted as acceleration rate and is expressed in Position Units/sec/sec. If
SCALE is set so one Position Unit equaled .001", then a value of 200 would represent an acceleration rate of
0.200 inches/sec/sec.
The relationship between the ramp distance, ACCELERATION and SPEED is:
SPEED x SPEED
Ramp Distance =

ACCELERATION x 2
SPEED x SPEED
ACCELERATION =

Ramp Distance x 2
In Mode 1, the ramp rate is one thousand times larger:
SPEED x SPEED
Ramp Distance =

ACCELERATION x 2000
In Mode 1, if one Position Unit equals .001", an ACCELERATION of 200 would represent an acceleration
rate of 200 inches/sec/sec.
In Mode 2, this parameter defines the distance to the specified SPEED, and in Mode 3, it defines the time to
the specified speed.