Danfoss vlt aqua Programming Guide

It may be preferable to run the pump at reduced speed for a while in case it is not possible to run
continuously with demanded capacity.
Select
Function at Inverter Overload , par 14-61 to automatically reduce pump speed until the
output current is below 100% of the rated current (set in
Derate Level , par. 14-62).
The
Function at Inverter Overload is an alternative to letting the frequency converter trip.
The frequency converter estimates the load on the power section by means of an inverter load
counter, which will cause a warning at 98% and a reset of the warning at 90%. At the value 100%,
the frequency converter trips and provides an alarm.
Status for the counter can be read in par. 16-35,
Inverter Thermal .
If par. 14-61,
Function at Inverter Overload , is set to Derate, the pump speed will be reduced
when the counter exceeds 98, and stay reduced until the counter has dropped below 90.7.
If par. 14-62,
Derate Level , is set e.g. to 95% a steady overload will cause the pump speed to
fluctuate between values corresponding to 110% and 95% of rated output current for the fre-
quency converter.
14-61 Function at Inverter Overload
Option: Function:
[0] Trip
[1]
*
Derate Is used in case of steady overload beyond the thermal limits
(110% for 60 sec.).
Choose
Trip [0] to make the frequency converter trip and pro-
vide an alarm or
Derate [1] to reduce pump speed in order to
decrease the load on the power section and allowing this to cool
down.
14-62 Derate Level
Range: Function:
95%
*
[75% - 95%] Defines the desired current level (in % of rated output current
for the frequency converter) when running with reduced pump
speed after load on the frequency converter has exceeded the
allowable limit (110% for 60 sec.).
VLT
®
AQUA Drive Programming Guide 2. Parameter Description
MG.20.O2.02 - VLT
®
is a registered Danfoss trademark 151
2

Danfoss vlt aqua Specifications

General

Brand	Danfoss
Model	vlt aqua
Category	DC Drives
Language	English