Siemens 411 Manuel D’Utilisation

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Issue 03/01 
10  Engineering Information 
MICROMASTER 411 & COMBIMASTER 411    Operating Instructions 
 
6SE6400-5CA00-0BP0 
119
 
10.1.4 I
2
t Performance 
When the motor is running at low speed and high load, the built-in cooling fan may 
not provide enough cooling and the motor may overheat.
 
Parameter P0610 allows 
a frequency dependent I
2
t limit to be enabled to protect the motor. 
When the inverter is operating in the region above the selected curve (i.e. at low 
frequency and high current), a timer is started, and after some time, (based on the 
current, the motor size and previous operating history), the inverter will trip or 
reduce output frequency.
 
Trip or reduction of output frequency will depend on the 
parameter setting. 
 
10.1.5 Internal 
Overtemperature 
Under normal circumstances, the inverter will not overheat.
 
The heatsink maintains 
the inverter at normal operating temperature.
 
Careful consideration when mounting 
the inverter will ensure adequate ventilation and reduce the likelihood of 
overheating.
 
Check to see that airflow remains unrestricted. There should be a 
minimum clearance of 100 mm free space around the Inverter. 
Heatsink temperature is monitored using a PTC resistor and the inverter will trip if 
the maximum temperature is exceeded.
 
If the inverter persistently trips, you should 
check for high ambient temperature or blocked airflow. 
You can verify heatsink temperature by displaying Parameter r0037.
 
Units are 
given in degrees Celsius (
o
C). 
10.1.6 
Overvoltage and Trip Levels 
The inverter will protect itself from both supply overvoltage and undervoltage.
 
Trip 
levels are shown in Table 10-2. Internal overvoltage can occur during braking 
where internal voltages are forced high by energy from an external load. 
Table 10-2   Trip Levels 
Input 
Supplies 
Undervoltage  
trip levels 
Overvoltage  
trip levels 
3 AC 400 V 
410 V 
820 V 
 
When output pulses are disabled from the inverter an undervoltage trip will not 
occur.
 
An overvoltage trip will occur at any time when the overvoltage threshold is 
exceeded. 
 
 
CAUTION 
Check to ensure you have matched the input supply to the inverter. If the supply 
voltage is too high, you may damage the inverter even if it trips.