Danfoss VLT Programming Guide

NB!
When flow compensation is used with the Cascade Controller (parameter group 25-**), the actual set-point will not depend on speed
(flow) but on the number of pumps cut in. See below:
There are two methods which can be employed, depending upon whether or not the Speed at System design Working Point is known.
Parameter used
Speed at
Design Point
KNOWN
Speed at
Design Point
UNKNOWN
Cascade Controller
Flow Compensation, 22-80 + + +
Square-Linear Curve Approximation, 22-81 + + -
Work Point Calculation, 22-82 + + -
Speed at No Flow, 22-83/84 + + -
Speed at Design Point, 22-85/86 + - -
Pressure at No Flow, 22-87 + + +
Pressure at Rated Speed, 22-88 - + -
Flow at Design Point, 22-89 - + -
Flow at Rated Speed, 22-90 - + -
22-80 Flow Compensation
Option: Function:
[0] * Disabled [0] Disabled : Set-Point compensation not active.
[1] Enabled [1]
Enabled :Set-Point compensation is active. Enabling this parameter allows the Flow Compensated
Setpoint operation.
VLT
®
HVAC Drive Programming Guide 3 Parameter Description
MG.11.C9.02 - VLT
®
is a registered Danfoss trademark 213
3

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)