Shop Arrow.com for thyristor surge protectors from leading manufacturers. Sort by specification and supplier to find the right component at a low price. 1 day shipping available.Surge protection devices, also known as surge protectors, surge limiters, or transient voltage suppressors (TVS) are an essential element of high power systems to protect against surges caused by lightning or sudden faults. Much lower rated devices are also used to protect costly machines and data circuits against surges on the line. Thyristor surge protection devices (TSPDs), a subclass of surge protectors, rely on a thyristor for surge protection through a crowbar action. The device is connected across the supply line in shunt with the load to be protected. At normal operating voltages the TSPD is in the OFF state, which means it has a very high resistance across its terminals allowing only a very small off-state current. If the line voltage exceeds the triggering threshold of the TSPD, it changes to the ON state and acts as a near short circuit, diverting the line current away from the protected load. This voltage is called the maximum off-state voltage and is selected below the voltage rating of the protected load.The thyristor is a latching device. Once fired, it will not switch off until the current falls below a ‘holding’ current value. In an AC circuit, the switch off is automatic near the next zero-crossing point. In a DC circuit, arrangements must be made to reduce the device current below the holding current once the surge is over. Important specifications of a TSPD include Maximum Off-State Voltage, Surge On-State Current, Off-State Current, Holding Current, On-State Voltage, and On-State Current. 더 읽기 읽기 안 함