GDT (gas discharge tube) is essentially a discharge gap sealed in a ceramic cavity filled with inert gas to stabilize the discharge voltage of the discharge tube. Its main features are large flow energy, which can reach tens to hundreds of KA, extremely high insulation resistance, no leakage, no aging failure, non-polarity bidirectional protection, and extremely small static capacitance. It is especially suitable for coarse protection. It can be widely used in the first-level lightning surge protection of various power and signal lines.
Its main parameters include:
1. Rated Voltage: The working voltage range of the gas discharge tube.
2. Leakage: The leakage current of the GDT gas discharge tube at a fixed voltage.
3. Strike Voltage: The voltage value when the GDT gas discharge tube starts charging and discharging.
4. Protection current : The current value of the gas discharge tube when it is working normally.
5. Time to Protection Current/Voltage: The reaction time under the protection current and voltage that the gas discharge tube can finally start.
The following points should be paid attention to when using GDT:
1. The selected GDT gas discharge tube should meet the design requirements and cannot exceed its maximum rated voltage and current.
2. The gas discharge tube is usually installed at the entrance of the circuit to be protected to provide the best circuit protection.
3. After the GDT gas discharge tube is charged and discharged, its internal capacitor will be discharged, which will form an instantaneous high voltage. Therefore, it is necessary to maintain the ground wire and guide wire, and avoid direct contact.
4. Do not change the parameters of the gas discharge tube or disassemble and repair it without authorization to avoid electrical hazards.
5. Proper selection and use of GDT gas discharge tube can greatly improve the withstand voltage level of electronic products, reduce circuit failures, and prolong the service life of electronic products.