Protection is the branch of electric power engineering concerned with the principles of design and operation of equipment (called 'relays' or 'protective relays') that detects abnormal power system conditions, and initiates corrective action as quickly as possible in order to return. Protection is the branch of electric power engineering concerned with the principles of design and operation of equipment (called 'relays' or 'protective relays') that detects abnormal power system conditions, and initiates corrective action as quickly as possible in order to return. So, protection relays are required in the electrical panel. Apart from overcurrent, protection relays are also categorised to protect from earth fault, abnormal voltage, or issues related to distance which can cause differential issues in transformers or other heavy voltage loads. They are intended to quickly identify a fault and isolate it so the balance of the system continue to run under normal conditions. The relays are in round glass cases. In electrical engineering, a protective relay is a relay device. Reliable real-time protection and control for critical power systems.
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