8017000000

Gas Discharge Tubes (GDTs) are an electronic component used to protect sensitive electrical and electronic devices against high voltage transients, such as lightning strikes, power line strikes or surges. They are sometimes referred to as "transient voltage surge suppressors" (TVSS), or simply "surge protection devices". GDTs have been in use since the late 19th century and are still in wide use today. GDTs are widely used in many applications, including telecommunications, power systems, medical equipment, appliances, and audio/video systems.

The basic principle of the GDT is simple. A GDT consists of a metal tube with a sealed end, usually made of thin metal or ceramic. The tube contains a noble gas, such as argon or neon, at a low pressure, typically 0.5 to 6 bar. When a surge or transient voltage appears on the GDT, the electric field inside the tube increases, ionizes the gas and breaks it down into positive and negative charges. This breakdown essentially short-circuits the voltage across the gap, preventing it from reaching the protected equipment.

In terms of application, GDTs are often used in industrial and commercial power systems as surge protection devices. They can be used to protect electrical equipment from transients between phase and phase, phase and ground, and neutral and ground. GDTs are also commonly installed in individual electronic devices to protect them from high voltage transients.

GDTs have several advantages over other surge protection devices such as solid state devices. GDTs are often more reliable and can withstand much higher voltages than solid state devices. They also provide a wider frequency range of protection than other surge protection devices. GDTs are also more cost effective than other surge protection devices in terms of installation and replacement costs. They are also more tolerant of environmental conditions, such as temperature and humidity, than other devices.

GDTs have some limitations as well. Since they operate at very high voltages, their installation requires specialized knowledge and tools. In addition, their performance is greatly influenced by environmental factors, such as temperature, humidity, and altitude. Finally, they have a limited lifetime, as the gas inside the tube gradually deteriorates with age. Nevertheless, when installed and maintained correctly, GDTs can provide effective and reliable surge protection for many years.