110
130BA260.10
105
100
95
60s
100
90.7
98
Current
% of rated
Time
Desired current>100%
Inverter
load
counter
Time
Warning
Warning
~
~
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
,
to automatically reduce pump speed until the
output current is below 100% of the rated current (set in
14-62 Inv. Overload Derate Current
).
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
If
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
14-62 Inv. Overload Derate Current
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 frequency converter.
14-61 Function at Inverter Overload
Option:
Function:
Is used in case of steady overload beyond the
thermal limits (110% for 60 sec.).
[0]
*
Trip
Choose Trip [0] to make the frequency converter trip
and provide an alarm.
[1]
Derate Derate [1] to reduce pump speed in order to
decrease the load on the power section and allowing
this to cool down.
14-62 Inv. Overload Derate Current
Range:
Function:
95 %
*
[50 - 100
%]
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.).
Parameter Description
VLT
®
HVAC Drive Programming Guide
108
MG.11.CB.02 - VLT
®
is a registered Danfoss trademark
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