The Application of a Small-Volume Neon-Filled Tube in Overvoltage Protection

To validate the performance of a small-volume neon-filled tube in overvoltage protection, the characterization of the neon-filled tube at p = 6.6 mbar and with 1-cm³ volume was performed. The characterization was performed using the mean value of electrical breakdown time delay t̅_d data as a function of relaxation period τ, applied voltage Uw, and discharge current I_g. On the basis of t̅_d data as a function of τ, it was shown that after discharge, the gas full recovery appears for τ ≈ 7 ms. The increase in the applied voltage in the case of full gas recovery leads to the decrease in t̅_d and for U_w ≥ 130 V, t̅_d ≈ constant. This proves the tubes efficient usage in overvoltage protection for applied voltages higher than 130 V. The increase in discharge current leads to the decrease in t̅_d in a considered τ interval. Other important processes that occur in discharge and afterglow, which are responsible for the initiation of electrical breakdown in neon-filled tube, were also analyzed.