Gas discharge tubes (GDT) are used for overvoltage protection in low voltage power distribution networks. GDTs are hermetically sealed cells where the gas mixture between two electrodes becomes ionized with a rise in voltage, and some amount of current flow is enabled.
Construction of the GDT cell consists of four or five pieces combined into a compact product through manufacturing processes that involve vacuum techniques, noble gasses, clean rooms, material degasification and hermetically sealed joints. High quality GDTs must have the following characteristics: a defined spark, the ability to quickly extinguish arc current, repeatable manufacturing processes, high insulation resistance, and they must be fire safe.
|Wide DC spark-over voltage (100 V/s, 1 mA)||600 V to 900 V|
|Many Model Sizes Available||Flat or cylindrical shape
(with or without terminals)
|High Peak Current Capability Imax (8/20 µs)
High Iimp Current Capability Iimp (10/350 µs)
|60 kA to 150 kA
12,5 kA to 100 kA