When designing a circuit, we often encounter the concepts of resistive load and inductive load. It will not only affect the use of related electrical components, but also affect the selection of transformers. Let's analyze it in detail:

First, we need to understand their definitions:

Resistive load: refers to the load that is resistive when there is no phase difference between the load current and the load voltage compared to the power supply, that is, a pure resistive load that works only through resistor-type components, such as incandescent lamps, electric furnaces, etc.;

Inductive load: Compared with the power supply, the load current lags behind the load voltage by a phase difference. In layman's terms, it refers to the load of high-power electrical products made by the principle of electromagnetic induction as loads, such as motors, compressors, relays, fluorescent lamps, etc.

When connecting an inductive load, what we need to consider is that at the moment of turning on or off the power supply, a back electromotive force voltage will be generated. This voltage is greater than the voltage value that the power supply can withstand, causing instantaneous overload and affecting the service life.

In addition, for inductive loads, we also need to consider the following points.

1. Current characteristics: Inductive loads contain inductive elements, which will generate a magnetic field after power is turned on, hindering the flow of current and causing a phase difference between current and voltage.

2. Power factor: The power factor of inductive loads is usually low, and the actual power utilization rate is not high, causing voltage fluctuations and energy waste in the circuit.

3. Starting current: Inductive elements will generate a large back electromotive force at the moment of power on, resulting in an increase in starting current. Special attention should be paid when using multiple inductive loads to prevent circuit overload.

4. Heating: The current of inductive loads is unstable and there is a large starting current, which may cause additional heating, and special attention should be paid to heat dissipation.

5. Circuit design: Capacitors and inductors are needed to balance the resistive, inductive and capacitive loads in the circuit to achieve the best power conversion efficiency and circuit stability. Energy is stored by parallel capacitors; when the inductive load needs energy, the energy is released by capacitors. Reduce the scale of energy exchange between load and power supply and reduce losses.