GE Industrial Solutions DV-300 DC Drive Users Manual - Manual (Page 157)

DV-300 Adjustable Speed Drives
——— FUNCTION DESCRIPTION ———
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The shape of the ramp is determined by the Ramp shape, S shape t constant, S dec t const parameters.
Ramp shape Linear Linear ramp
S shaped S-shaped ramp
S shape t const Determines the curve for S-shaped ramps (see Figure 6.6.2.1).
S shape t const
Figure 6.6.2.1: Ramp shape
The value of S shape t constant is added to the ramp time of linear ramps. The ramp time is thus lengthened by
the value degined by the S shape t const parameter. This is done regardless of the speed changed involved!
S acc t const
Determines the curve for S-shaped acceleration ramps.
S dec to const Determines the curve for S-shaped deceleration ramps.
Using very different S acc t const and S dec t const values it is possible to have a discontinuous behaviour dur-
ing the changing of the motor direction.
Speed changes (=Active ramp) are indicated by the Ramp + and Ramp - parameters.
Ramp +/- delay Defines a delay time. It is only valid if the ramp is active.
Ramp +
Ramp -
Ramp
output
Ramp +/- delay
Figure 6.6.2.2: Ramp delay