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Hi, this is the Industrial Control Assistant. Today, I’ll share with you the differences between reactors and filters in Siemens frequency converters. Come and take a look. On the output side of the inverter, there are the following options: 1) Output reactor – this is used when the length of the cable connecting the inverter to the motor exceeds the value specified by the manufacturer. The output reactor helps to compensate for the effects of charge and discharge of the coupling capacitance that occur when the motor is connected via a long cable, thereby preventing overcurrent in the inverter. There are two types of output reactors; one type is the core-type reactor, which is used when the carrier frequency of the inverter is less than 3 KHZ. Another type of output reactor is the ferrite type, which is used when the carrier frequency of the inverter is less than 6 KHZ. The purpose of adding an output reactor at the output terminal of the inverter is to increase the distance between the inverter and the motor. The output reactor can effectively suppress the sudden high voltages that occur when the IGBTs in the inverter switch, thereby reducing the adverse effects of such voltages on the cable insulation and the motor. At the same time, to increase the distance between the inverter and the motor, the cable can be made thicker appropriately to enhance its insulation strength; unshielded cables should be preferred whenever possible. 2) The Outputdv/dtfilter outputs a dv/dt reactor; this reactor is used to limit the rate of increase of the inverter’s output voltage, thereby ensuring proper insulation of the motor. 3) Sinusoidalfilters, which are sine wave filters, enable the output voltage and current of the inverter to be close to sine waves, thereby reducing the motor’s harmonic distortion factor and the stress on the motor’s insulation. The following options can be added to the input side of the inverter: 1) an input EMC radio interference filter, whose purpose is to reduce and suppress the electromagnetic interference generated by the inverter. There are two types of EMC filters: Class A and Class B filters. EMCA-class filters are used in the second category of applications, namely industrial applications, and meet the EN50011A standard. EMCB-rated filters are primarily used in the first category of applications, namely civilian and light industrial applications, and meet the EN50011B standard. 2) InputReactor: The input reactor can suppress harmonic currents, improve the power factor, and reduce the impact of surge voltages and currents in the input circuit on the inverter; it also helps to mitigate the effects of uneven supply voltages. In general, an input reactor must always be installed. Today’s little tip may seem simple, but it actually requires careful attention to be understood. The little assistant also spent a long time learning it; follow the little assistant every day to learn and make progress together. Feel free to subscribe!