Danfoss VLT Programming Guide

3.23 Main Menu - Cascade Controller - Group 25
3.23.1 25-** Cascade Controller
Parameters for configuring the Basic Cascade Controller for sequence control of multiple pumps. For a more application oriented description and wiring
examples, see Chapter
Application Examples, item Basic Cascade Controller in the Design Guide.
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 parameter can normally be set in advance.
Parameters in 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.
NB!
The Cascade Controller is supposed to operate in closed loop controlled by the built-in PI controller (Closed Loop selected in
Configu-
ration Mode
, par. 1-00 Configuration Mode ). If Open Loop is selected in par. 1-00 Configuration Mode , all fixed speed pumps will be
destaged, but the variable speed pump will still be controlled by the frequency converter, now as an open loop configuration:
3 Parameter Description VLT
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HVAC Drive Programming Guide
240 MG.11.C9.02 - VLT
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Danfoss VLT Specifications

General

Frequency	50/60 Hz
Enclosure	IP20, IP21, IP55, IP66
Series	VLT
Control Technique	Flux Vector Control
Output Voltage	0-Vinput
Control Method	Fieldbus
Communication Interface	PROFIBUS, CANopen
Protection Features	Overload, Overvoltage, Undervoltage, Short Circuit, Ground Fault
Cooling Method	Liquid Cooled
Storage Temperature	-25°C to +70°C
Relative Humidity	5-95% non-condensing
Altitude	Up to 1000m (3280ft) without derating, up to 4000m (13120ft) with derating
Operating Temperature	-10°C to +50°C (14°F to 122°F)