Danfoss VLT Aqua Drive FC 202 Programming Manual page 552

Programming Guide | VLT® Aqua Drive FC 202
Use this option only if [1] Soft starter or [2] Star-Delta is selected in parameter 25-02 Motor Start.
When adding a fixed-speed pump controlled by a soft starter or a star-delta starter, it is possible to delay the ramp down of the lead
pump until a preset time after the start of the fixed-speed pump. This delay eliminates pressure surges or water hammer in the system.
Staging
Speed
Fixed-speed pump
(controlled by soft starter)
t 1
P PC-40
Lead pump starts
to ramp down
Cascade Controller
calls for another
pump
Figure 121: Staging with Ramp-down Delay
25-41 Ramp Up Delay
Default value:
2 s
Setup: All setups
Data type:
Uint16
Use this option only if [1] Soft starter is selected in parameter 25-02 Motor Start.
When removing a fixed-speed pump controlled by a soft starter, it is possible to delay the ramp up of the lead pump until a preset time
after the stop of the fixed-speed pump. This delay eliminates pressure surges or water hammer in the system.
552 | © 2024.06
Lead pump
(controlled by drive)
Time
NOTICE
Parameter type:
Conversion index:
Change during operation:
NOTICE
Parameter Descriptions
Range, 0 - 12 s
-1
True
AU361182657213en-002101 / 130R0338