Programming
Page
D-150
890CS Common Bus Supply - Frames B & D; 890CD Common Bus Drive and 890SD Standalone Drive - Frames B, C & D
8
9
10
A
B
C
D
E
1
2
3
4
5
6
7
Functional Description
The SLEW RATE LIMIT block obtains the setpoint from the output of the application, correctly scaled by the REFERENCE
block. The rate of change limits are applied and the setpoint is then passed on for further processing.
When the braking block determines that the internal dc link voltage is too high it issues a Hold signal. This causes the SLEW
RATE LIMIT block to hold the setpoint at its current value. This typically lasts for only 1ms, time for the excess energy to be
dumped into the dynamic braking resistor.
SETPOINT
DECEL LIMIT
ACCEL LIMIT
HOLD SIGNAL
Note
If the drive is part of a common DC link/bus system set the ENABLE parameter to FALSE. This disables ramp-hold
during deceleration on high link volts feature.