See more. Without some form of overcurrent protection device installed in series with the circuit conductors, the only limit of the fault overcurrent is the conductor resistance and the amount of power available from the transformer. The basic rule for overcurrent protection of conductors—other than using flexible cords, flexible cables, and fixture wires—is to protect the conductor in accordance with the ampacities specified in Section 310.15. Definition of overcurrent in the Definitions.net dictionary. In an electric power system, overcurrent or excess current is a situation where a larger than intended electric current exists through a conductor, leading to excessive generation of heat, and the risk of fire or damage to equipment. For instance, a #14 wire can safely carry 15 amps and should be protected by a 15-amp breaker. Meaning of overcurrent. This can cause overheating, the effects of which can range from minor degradation of cycle life to a catastrophic thermal runaway. The causes may include: The motor suffers an impact load or the transmission mechanism is stuck, which leads to sudden increase of the motor current. What does overcurrent mean? Electrical circuit overloads happen when more amperage is put across an electrical wire or circuit than it can handle. What is a power supply’s OCP? Over-current and overload are abnormal conditions occurring in a circuit. Overcurrent definition, a current of a magnitude that is greater than a limiting value, as the value at which a fuse melts. Depending on how much the rating is exceeded, the tolerable time decreases. This article well explains the difference between over-current and overload. Information and translations of overcurrent in the most comprehensive dictionary definitions resource on the web. Any situation in which the current flow through a device or conductor exceeds the desired value is known as over current. Overcurrent in VFD working refers to the overcurrent of the driving system occurs in the working. Possible causes for overcurrent include short circuits, excessive load, incorrect design, an arc fault, or a ground fault. The meaning of a PSU’s overcurrent protection function and multi-rail vs. single-rail PSUs explained. Difference between over-current and overload Over-current. Overcurrent occurs if the device draws currents larger than the manufacturer-recommended rating for various periods of time. The general requirement for overcurrent protection of conductors is provided in Section 240.4, Protection of Conductors. Overcurrent definition is - an electrical current whose intensity is higher than a specified amount. These devices typically consist of a manual circuit breaker or contactor and a current sensing relay which interlocks with it. 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