Danfoss VLT AQUA FC 200 Series Programming Manual page 216

2 Parameter Description
25-24 SBW Destaging Delay
Range:
15 s* [0 - 3000 s]
2
25-25 OBW Time
Range:
10 s* [0 - 300 s]
25-26 Destage At No-Flow
Option:
[0] * Disabled
[1] Enabled
216
Function:
Immediate destaging of a fixed speed pump is not desirable when a momentary pressure increase
in the system that exceeds the Staging Bandwidth (SBW). Destaging is delayed by the length of
time programmed. If the pressure decreases to within the SBW before the timer has elapsed, the
timer is reset.
Function:
Staging a fixed speed pump creates a momentary pressure peak in the system, which might exceed
the Override Bandwidth (OBW). It is not desirable to destage a pump in response to a staging
pressure peak. The OBW Time can be programmed to prevent staging until the system pressure
has stabilized and normal control established. Set the timer to a value that allows the system to
stabilize after staging. The 10 second factory setting is appropriate in most applications. In highly
dynamic systems, a shorter time may be desirable.
Function:
The Destage at No-Flow parameter ensures that when a no-flow situation occurs, the fixed speed
pumps will be destaged one-by-one until the no-flow signal disappears. This requires that No Flow
Detection is active. See par. 22-2*.
If Destage at No-Flow is disabled the Cascade Controller does not change the normal behavior of
the system.
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VLT AQUA Drive Programming Guide