Acceleration AccSet

I understand the concept of accel and decel, trapezoidal movements very well, but can someone make clear the usage of AccSet for me?

What is the difference between over ride and ramp?  It almost sounds like "ramp" adds some s-curve to the motion profile but I find the manual a little vague on this command.  I could just play around with the numbers but if someone knows what the relationships are for the 2 variables of AccSet I would appreciate some minor enlightenment.




  • Hi,

    AccSet have two parameters, one for the acceleration and one for the ramp. the values are expressed in percentage and you can not increase them over 100 (the system is already accelerating as high as possible).

    The acc parameter determines the acc/dec you want and the ramp parameter determines how quick you want to reach that acc/dec. Alower value will give a slower change in the acc/dec an if it is too low you will never reach the acc/dec you wanted.

    On the other hand the ramp is really useful if you want to avoid ocillations/shaking in an weak axis. The standard ramp can sometimes "kickstart" an unwanted oscillation and a decrease of the ramp value (slower ramp) can help the situation
  • So would the ramp number act as the equivalent of S-curve on typical drive accel/decel, rounding off the normal trapezoidal profile?
  • Stew
    Stew United States
    I always think of AccSet in terms of a graph of v/t.

    Acc is related to the time spent reaching the requested velocity- the slope of the line.
    Ramp is related to the curvature of the plot during that acceleration time.
    (similar shapes for deceleration)

    One thing to note- the lowest setting available with AccSet is a value of 10 in either field.

    I hope that helps-

  • PetrB
    PetrB Czech
    Very good picture from help for instruction AccSet