diode   Transistor  Patch discharge tube

Ceramic discharge tube
The ceramic discharge tube is sealed by a ceramic capacitor, and the inside is composed of two or more metal electrodes with gaps, which are filled with an inert gas of argon gas and helium gas. When the voltage applied to the two electrode ends reaches a gas breakdown in the gas discharge tube, The gas discharge tube begins to discharge, from high impedance to low impedance, so that the surge voltage is quickly shorted to near zero voltage, and the overcurrent is released to the ground, thereby protecting the subsequent circuit.

working principle

The ceramic discharge tube is sealed by a ceramic capacitor, and the inside is composed of two or more metal electrodes with gaps, which are filled with an inert gas of argon gas and helium gas. When the voltage applied to the two electrode ends reaches a gas breakdown in the gas discharge tube, The gas discharge tube begins to discharge, from high impedance to low impedance, so that the surge voltage is quickly shorted to near zero voltage, and the overcurrent is released to the ground, thereby protecting the subsequent circuit. When the surge voltage disappears, the ceramic discharge tube is extinguished and restored to a high-impedance state, waiting for the next action. The ceramic discharge tube is often used in the first or first stage of the multi-stage protection circuit to discharge the lightning transient overcurrent and Limit the effect of overvoltage.

Ceramic discharge tube product selection
1: The lower limit of the DC breakdown voltage is higher than the maximum normal operating voltage of the line.
2: The impact breakdown voltage value is lower than the highest instantaneous overvoltage that may occur on the line.
3: The outdoor equipment is selected to be 10KA or higher, the indoor equipment entrance is selected below 10KA, and the equipment terminal is selected below 5KA.
4: According to the size of the product, select the discharge tube of the appropriate size.

Ceramic discharge tube test report
1. DC discharge voltage test:
1. Test test circuit Figure 1. C-200μf/1KV, A-- ammeter. V--voltmeter, RM-02 ceramic discharge tube.
W = 1/2 CxUxU = 25 joules.
2. Test data:
1) DC discharge voltages are: 519; 540; 552; 560; 512; 490; 575; 576; 512; 550; 560; 540; 560; 590; 610; 640;
2) The insulation resistance of the ceramic high-voltage discharge tube RM-02 before and after the test is greater than 200 megohms.
3) The discharge is instantaneously accompanied by a flash in the discharge tube. The ceramic discharge tube can still work normally after thousands of discharge tests.
2. Power frequency discharge voltage test:
1. Test test circuit Figure 2. Series current limiting resistor R = 20 kΩ. A-- ammeter, V--voltmeter, RM-02 ceramic discharge tube. Power frequency regulator L--0-250V.T--Power frequency high voltage transformer 220V/100KV.
2. Test data: 1) Power frequency discharge voltage U=1KV.AC.
2) When the series current limiting resistor R=20 kohm, the discharge voltage of the discharge tube is U=850V.AC.
3. DC arc extinguishing performance test: 1. Test test circuit Figure 3. C = 4μf. L---high frequency current limit line