Small power resistor is typically packaged in plastic housing composition of carbon

Small power resistors are usually enclosed in the plastic housing of the carbon film, the power resistor is Voltage stabilizer resistor, by the large resistance of the metal wire around the heart and the ceramic material.
If the resistance value of a resistor close to zero ohms (for example, the large cross-section between two wires), the resistor of the current does mcb circuit breaker this series circuit the resistor is short-circuited, the current infinity. If a resistor having infinite or a large resistor is connected in series to the resistor can be seen as an open circuit, the current is zero. Commonly circuit breakers resistor between the two extremes, it has a certain resistance through a constant current, but the current is not as large as a short circuit. Limiting resistor works like two large diameter pipes connected to the small-diameter pipe between the water flow restriction effect.