Siemens inverter F021 failure - Solutions - Huaqiang Electronic Network

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Inverter F021 fault, find the manual prompts I2T monitoring exceeds the limit value, change the corresponding limit value of the motor, it will not alarm, I would like to ask the experts, what does I2T mean? Can you explain it in detail!
A: F021 -

Motor overheat protection, which is a malfunction in temperature monitoring. First of all, the more accurate setting parameter P383 (motor thermal time constant) is one of the most effective ways to avoid F021 false positives.

I2T, the current squared value of the motor multiplied by time, is a characterization parameter for the thermal energy of the motor.

In the P383 table, the thermal time constants of the siemens conventional motors are listed. Motors from other manufacturers can refer to their data.

If you are sure that your motor current is not large and there is no overload or heat, you can lengthen the P383 parameter appropriately. In addition, it is necessary to check whether the motor fan is working properly and the ventilation is good.

Personal advice is, if you are not using Siemens original motor, then this monitoring function is best not to use well, so as to avoid unnecessary alarm malfunction.

Regarding I2t protection, some engineers have suggested shielding it, mainly because it is too indirect and not very useful. General overload protection is mainly based on the limitation and control of current. It is not enough to rely on I2t.

Under normal circumstances, temperature measuring components such as PT100 or PTY have been pre-embedded in the windings of the motor. Then in the upper control system (such as plc) to monitor the temperature of the motor, and do some related numerical display and protection. Simply relying on the frequency converter to monitor the temperature of the motor is less and less.

I guess you should also have a higher-level control system, then directly transfer the temperature analog of the PT100 to the monitoring system, and cancel the temperature monitoring alarm of the inverter. We have always done this, it is convenient, and it is not easy to false alarm.

If the parameter P383=0 is set, this can mask the F021 fault to avoid the trouble caused by false alarm. Users can think about it.