Over-current and overload are abnormal conditions occurring in a circuit. 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. The meaning of a PSU’s overcurrent protection function and multi-rail vs. single-rail PSUs explained. The possibility of over current in electric current is bigger than short circuit, especially when electric motor switches on and has positive and negative inversion frequently. Information and translations of overcurrent in the most comprehensive dictionary definitions resource on the web. See more. What is a power supply’s OCP? Overcurrent is generally smaller than short circuit current and within 6 times of the rated current. These devices typically consist of a manual circuit breaker or contactor and a current sensing relay which interlocks with it. Meaning of overcurrent. Depending on how much the rating is exceeded, the tolerable time decreases. Difference between over-current and overload Over-current. What does overcurrent mean? Overcurrent definition is - an electrical current whose intensity is higher than a specified amount. 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. Overcurrent definition, a current of a magnitude that is greater than a limiting value, as the value at which a fuse melts. This article well explains the difference between over-current and overload. Electrical circuit overloads happen when more amperage is put across an electrical wire or circuit than it can handle. Any situation in which the current flow through a device or conductor exceeds the desired value is known as over current. For instance, a #14 wire can safely carry 15 amps and should be protected by a 15-amp breaker. Overcurrent in VFD working refers to the overcurrent of the driving system occurs in the working. Definition of overcurrent in the Definitions.net dictionary. 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. Possible causes for overcurrent include short circuits, excessive load, incorrect design, an arc fault, or a ground fault. Overcurrent occurs if the device draws currents larger than the manufacturer-recommended rating for various periods of time. 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 general requirement for overcurrent protection of conductors is provided in Section 240.4, Protection of Conductors. 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