Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

Historical development factorEarly power systems were dominated by alternating current: In the early days of power system development, alternator and transformer technology was relatively mature and easy to manufacture.Ac system can easily change the voltage level through the transformer to achieve high-voltage transmission to reduce line losses, so AC transmission has been widely used in the early days and formed a huge power grid system.Technical considerationsAdvantages of transformers in AC

Will the voltages of two different currents drawn from an AC source add up?The voltages of two different currents drawn from an AC (Alternating Current) source do not simply add up in the way that might be expected with direct current (DC) sources. To understand why, it's important to consider how voltage and current behave in AC circuits.Key Concepts in AC CircuitsImpedance (Z): In AC circuits, impedance is the measure of the total opposition that a circuit presents to a current due to the pres

What is the maximum current safe for the human body?The effect of electric current on the human bodyPerceptual threshold0.5 mA to 1 mA: This is the threshold at which most people can feel the current pass through. In this range, the body will feel a slight tingling or tingling sensation.Relaxation threshold5 mA to 10 mA: In this range, the current is sufficient to cause muscle contraction, making it difficult for the finger or hand to release the power voluntarily. This is called the "letting go

Comparison of Current Effects on Resistors vs. Capacitors and Inductors (Reactive Elements)When comparing the effects of current on resistors to those on capacitors and inductors (reactive elements), we need to understand how each component behaves differently under the influence of current.Impact of Current on ResistorsBasic Properties of ResistorsA resistor is a purely resistive element whose primary function is to impede the flow of current and convert electrical energy into heat. The resista

Distinction Resistance: impedes current and dissipates energy. Inductance: Stores magnetic field energy and opposes current changes. Capacitors: Store electric field energy and oppose voltage changes. Voltage: The force that drives the flow of electricity. Current: The flow of charge, indicating the rate at which charge flows. Power: The work done per unit time, indicating the rate of energy conversion.Resistance definitionResistance is a physical quantity in a circuit that impedes the flow of c

Calculating the maximum load of a fuse usually involves determining the rated current of the fuse and the maximum allowable current of the circuit it protects.ProcedureDetermine the rated current of the circuitFirst you need to know the current required by the load in the circuit when it is working normally. This can usually be found on the device's nameplate or specification sheet.Determine the rated current of the fuseThe rated current of the fuse means that the fuse will not blow if it does n

Short circuit protectionShort circuit protection means that when there is a short circuit fault in the circuit, the protection device can quickly cut off the power supply to prevent the equipment and line from being damaged by too much current. A short circuit is usually caused by the direct shorting of the wires in the circuit, resulting in a direct reflux of current without the load.Peculiarity High current: Short circuit will cause the current to increase sharply, usually far more than the no

Neutral (N)A neutral line, usually denoted by the letter "N", is a wire in an alternating current system whose main function is to provide a return path in the circuit. In a single-phase AC system, the neutral line is usually connected to the reference point of the power supply (usually ground) and together with the live line forms a complete circuit.Features Voltage: The neutral line is usually zero voltage (or very close to zero voltage) relative to ground, although there may be some voltage d

What is Primary Load?Primary load definitionPrimary load refers to those loads that have very high demands on the power supply, and these loads may lead to serious consequences, such as life danger, significant economic losses, production stagnation, etc., if the power is cut off or the power is interrupted. Primary loads usually require a reliable power supply and often require a backup power system to ensure continued operation in the event of a primary power failure.Characteristics of primary

What is a Spike Current?Peak current definitionPeak current refers to the short and strong current peak that suddenly appears at the moment of startup of some electrical equipment or under certain conditions. Peak current usually occurs at the moment when the device is just switched on, at which time the internal circuit of the device may temporarily show a low impedance state, resulting in a sharp rise in current. The peak current has a great influence on the safety and reliability of electrica