Elettronica Santerno SINUS/ISD 200 S-0.75, User Manual, Page: 88 / 206

15P0082B8
USER MANUAL
SINUS/ISD
6 - 32/82
6.4.1.19 I*t TRIP
This function block is designed to
protect the motor and the inverter from
damage that may be caused by
continuous operation beyond
specification.
Functional Description
The I*t UPPER LIMIT, I*t THRESHOLD and I*t TIME parameters effectively define how long the output current
may exceed the I*t THRESHOLD . For example, if the output current equals the I*t UPPER LIMIT then the trip
will occur after I*t TIME . Alternatively, if the output current exceeds the I*t THRESHOLD by only half as much as
the I*t UPPER LIMIT then the trip will occur after twice the I*t TIME .
As the output current is constantly monitored by the Inverter the I*t TRIP block constantly updates the time at
which a trip might occur, taking into account not only the present output level but also the recent history. For an
output current that moves around the I*t THRESHOLD level, the time for which the current is below the level is
used to balance the time for which the current is above the level. This avoids spurious trips while maintaining the
monitoring function.
To protect against erroneous set-up an “I*t TRIP SETUP” trip will occur if the inverter is enabled with the I*t
UPPER LIMIT less than the I*t THRESHOLD .
Refer to Chapter 7 for a description of the trips supported by the Inverter.
MMI Menu Map
1
SETUP PARAMETERS
2
FUNCTION BLOCKS
3
TRIPS
4
I*T TRIP
I*T THRESHOLD
I*T TIME
I*T UPPER LIMIT
I*t TRIP
105.00 % – [237] I*t THRESHOLD –
60 s – [238] I*t TIME –
150.00 % – [239] I*t UPPER LIMIT –
Parameter Descriptions
I*t THRESHOLD Range: 50.00 to 105.00 %
If the magnitude of the current delivered by the Inverter is greater than this threshold
then the inverter will trip after a time determined by I*t TIME and I*t UPPER LIMIT .
This parameter must be less than the I*t UPPER LIMIT .
I*t TIME Range: 5 to 60 s
The trip delay time for a constant output current equivalent toI*t UPPER LIMIT .
I*t UPPER LIMIT Range: 50.00 to 150.00 %
The output current level used to determine the trip delay. Used in conjunction with I*t
TIME .
This parameter must be greater than I*t THRESHOLD .
Time
Current
Area that defines how
long the output may
exceed the threshold.
Example of current
output that causes
a trip.
Upper limit
Threshold
I*t TIME