Danfoss VLT AQUA Programming Manual page 230

2. Parameter Description
25-20 Staging Bandwidth [%]
Range:
10%
2
25-21 Override Bandwidth [%]
Range:
100% =
Disa-
bled
230
Function:
* [1 - 100 %] Set the staging bandwidth (SBW) percentage to accommodate
normal system pressure fluctuation. In cascade control systems,
to avoid frequent switching of fixed speed pumps, the desired
system pressure is typically kept within a bandwidth rather than
at a constant level.
The SBW is programmed as a percentage of par. 3-02 Minimum
Reference and par. 3-03 Maximum Reference. For example, if
the set-point is 5 bar and the SBW is set to 10%, a system
pressure between 4.5 and 5.5 bar is tolerated. No staging or de-
staging will occur within this bandwidth.
Function:
[1 – 100%] When a large and quick change in the system demand occurs
(such as a sudden water demand), the system pressure rapidly
*
changes and an immediate staging or destaging of a fixed speed
pump becomes necessary to match the requirement. The over-
ride bandwidth (OBW) is programmed to override the staging/
destaging timer (par. 25-23/25-24) for immediate response.
The OBW must always be programmed to a higher value than
the value set in
is a percentage of par.3-02 Minimum Reference and par. 3-03
Maximum Reference..
MG.20.O2.02 - VLT
®
VLT AQUA Drive Programming Guide
Staging Bandwidth
(SBW), par. 25-20. The OBW
®
is a registered Danfoss trademark