Overcurrent protection is generally a protection against short circuit where excessive current starts to flow in the circuit which leads to damage the connected equipment. #    Overcurrent Protection and Overcurrent Protection Devices. Overload protection devices are a type of OCPD that are designed to protect against sustained overcurrent, and they include the use of relays and “slow blow” fuses. The ability of a particular overcurrent protection device to interrupt a given level of overcurrent depends on the device sensitivity. 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The unit protection schemes is based on Kirchhoff’s Current Law – the sum of the currents entering an area of the system must be zero. 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 … O    W    For further details, the individual Series Data Sheets may be downloaded. Overcurrent protection is seen to be a series connection of cascading current-interrupting devices. An overcurrent is any situation in which the amount of current (amperes) in a system (e.g., an electrical circuit) exceeds the amount of current that the system is designed to safely handle. What is the difference between safety glasses and goggles? Overcurrent protection is protection against excessive currents or current beyond the acceptable current rating of equipment. RCBOs are devices which feature an integrated overcurrent protection unit for overload and short-circuit protection in addition to protection against residual currents. Protection is assured through detaching power supply in a circuit through overcurrent protection , which removes fire hazards and electrocution. Back-up is an important function in overload protection. III Types of Overcurrent Protection. Protection coordination is the method of selecting and coordinating overcurrent protective devices to minimise the risk of a short circuit in a small area. They are utilized in every conceivable electrical system where there is the possibility of overcurrent damage. Proper grounding of service boxes and equipment can mitigate this risk. At these and higher currents, the magnetic detection mechanism within the thermal-magnetic unit is dominant. 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