The Gas Discharge Tube(GDT) is a protective device which is filled with certain proportion of noble gas, or mixed gas or other discharge media in the space between metal electrodes and metalized ceramics,and then sealed at high temperature to form a single-gap or multi-gap switch type protective device.When the protected circuit or equipment suffers to surge, GDT will change from high impedance state to low impedance state and release the surge energy to reduce the residual voltage of the circuit, and then protect the equipment or humanbody from the hazard of transient overvoltage.
SETsafe | SETfuse GDT product the voltage range 70 to 4500 V,and surgecurrent (@8/20 μs) range 0.5 to 200 kA. It is widely used in the overvoltage protection of signals, power supplies and various ports; safety regulations Certificates include UL, cUL, TUV, and it meets for RoHS & REACH requirements.
●Antenna and RF
●N-PE Protection in AC Power
D.C. Spark-over Voltage
The voltage at which the GDT sparks over with slowly increasing d.c. voltage.
Impulse Spark-over Voltage
The highest Voltage which appears across the terminals of a GDT in the period between the application of an impulse of given wave-shape and the time when current begins to flow.
Voltage drop across the GDT during arc current flow.
The peak value of the voltage drop across the GDT when a glow-current is flowing, It is sometimes called the glow mode voltage.
8/20 Current Impulse
Current impulse with a nominal virtual front time of 8 µs and a nominal time to half-value of 20 µs.
1.2/50 Voltage Impulse
Voltage impulse with a nominal virtual front time of 1.2 µs and a nominal time to half-value of 50 µs.
Alternating Discharge Current
The r.m.s. value of an approximately sinusoidal alternating current passing through the GDT.
Nominal Discharge Current
Crest value of the current through the GDT having a current waveshape of 8/20 µs.
Maximum Discharge Current
Crest value of a current through the GDT having an 8/20 µs waveshape and magnitude according to the manufacturers specification. Imax is equal to or greater than In.
1. Do not operate GDT in power supply networks, whose maximum operation voltage exceeds the minimum spark-overvoltage of the GDT.
2. The GDT may become hot in the event of longer periods of current stress (burn risk). In the event of overload the connectors may fail or the component may be destroyed.
3. If the contacts of GDT are defective, current load can cause sparks and loud noises.
4. When air pressure is from 55 kPa to 106 kPa. The relative altitude shall be +5000 m to –500 m.
The GDT is a non-repairable product for safety sake, please use equivalent GDT for replacement.
The packaged GDT shoud be placed in a dry, ventilted and non-corrosive environment.
Do not install the GDT in a touchable position.
Do not take violent action such as knocking when assembling, to avoid product failure.