Basic concepts

Power in AC Circuit

Power in AC Circuit The instantaneous power of an AC waveform is given by p(t) = v(t) · i(t) Power in a Resistance The current and voltage are in phase on the resistor (Fig. 1). For a sinusoidal voltage, the instantaneous power is Here V and I are the RMS values of the voltage and […]

Power in AC Circuit Read More »

MCCB Circuit Breakers

Molded Case Circuit Breakers or MCCB circuit breakers are black plastic–cased automatic switches. They are designed to primarily protect insulating materials from overheating. Molded case circuit breakers (MCCB) are by far the most commonly used breakers in residential, commercial, and industrial facilities. When an MCCB has opened (or “tripped”) to protect the circuit, it can

MCCB Circuit Breakers Read More »

What is power factor?

The term “power factor” (PF) is an expression of the relationship between the peak voltage and the peak current. Stated differently, the power factor is an expression of how far out of phase the voltage and current are to each other.  What is power factor? Figure 1 shows both voltage and current peaks occurring at

What is power factor? Read More »

Fuse Selection Criteria

The fuse provides protection by melting away a thin metal link in the faulted circuit. The metal link may be of silver, copper, or nickel, silver being more common for long-term performance stability. The fuse body is generally filled with a sand-type filler (Figure 1) to suppress sparks when the fuse link melts and interrupts the

Fuse Selection Criteria Read More »

Thevenin Theorem Examples

Thevenin’s theorem is very useful in solving electrical networks which may not be easily solved by other methods. In this article, I will discuss this theorem and show some of the thevenin theorem examples to make this theorem easily understandable. Thévenin’s theorem is a circuit analysis technique that reduces any linear bilateral network to an equivalent

Thevenin Theorem Examples Read More »