Parameters: 25-** Cascade Controller - Danfoss VLT CDS302 Operating Instructions Manual

Parameter Descriptions

6.14 Parameters: 25-** Cascade Controller

Parameters for configuring the Basic Cascade Controller for
sequence control of multiple compressors.
Illustration 6.25 Cascade Controller Feedback Signals
MG34M302 - VLT
®
Operating Instructions VLT
To configure the Cascade Controller to the actual system
and the desired control strategy, it is recommended to
follow the below sequence, starting with parameter group
25-0* System Settings, and next parameter group 25-5*
Alternation Settings. These parameters can normally be set
in advance.
Parameters in parameter group 25-2* Bandwidth Settings
and 25-4* Staging settings will often be dependent on the
dynamic of the system and final adjustment to be done at
the commissioning of the plant.
NOTE
The Cascade Controller is supposed to operate in closed
loop controlled by the built-in PI controller ([1] Speed
Closed Loop selected in 1-00 Configuration Mode). If [0]
Speed Open Loop is selected in 1-00 Configuration Mode, all
fixed speed compressors will be destaged, but the variable
speed compressor will still be controlled by the frequency
converter, now as an open loop configuration:
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is a registered Danfoss trademark/Commercial Compressor
CDS302 and CDS303
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