6.1.4 Bandwidth Settings, 27-2*
Parameters for configuring control response.
27-20 Normal Operating Range
Range:
Function:
10%*
[1% – P27-21]
Normal Operating Range is the allowed offset from the setpoint before a pump may be added or
removed. The system must be outside this limit for the time specified in P27-23 (Staging) or P27-24
(De-staging) before a cascade operation takes place. Normal refers to the system operating with at
least one variable speed pump available. This value is entered as a % of Max Reference (See P21-12
in the
VLT AQUA Drive Programming Guide
for further information).
27-21 Override Limit
Range:
Function:
100% (Dis-
abled)*
[P27-20 - 100%]
Override Limit is the allowed offset from the setpoint before a pump will immediately be added or
removed (for instance, if a fire tab is switched on). Normal Operating Range includes a delay that
limits the system response to transients. This makes the system respond too slowly to large demand
changes. The override limit causes the drive to respond immediately. The value is entered as a %
of Max Reference (P21-12). Override operation may be disabled by setting this parameter to 100%.
6 How to Program
Extended and Advanced Cascade Controller
Option
6-4
MI.38.C2.22 - VLT
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