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. Depending on how much the rating is exceeded, the tolerable time decreases. An overcurrent relay is an electrical protection device designed to cut off the power supply to a circuit, appliance, or machine in the event of an overload or failure. Electrical circuit overloads happen when more amperage is put across an electrical wire or circuit than it can handle. 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. What is a power supply’s OCP? Overcurrent definition, a current of a magnitude that is greater than a limiting value, as the value at which a fuse melts. These devices typically consist of a manual circuit breaker or contactor and a current sensing relay which interlocks with it. See more. The general requirement for overcurrent protection of conductors is provided in Section 240.4, Protection of Conductors. 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. Over-current and overload are abnormal conditions occurring in a circuit. Overcurrent is generally smaller than short circuit current and within 6 times of the rated current. 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. Overcurrent definition is - an electrical current whose intensity is higher than a specified amount. For instance, a #14 wire can safely carry 15 amps and should be protected by a 15-amp breaker. Overcurrent occurs if the device draws currents larger than the manufacturer-recommended rating for various periods of time. 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. Meaning of overcurrent. 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 meaning of a PSU’s overcurrent protection function and multi-rail vs. single-rail PSUs explained. What does overcurrent mean? Difference between over-current and overload Over-current. Definition of overcurrent in the Definitions.net dictionary. 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