z72B, 72BL Series Nominal Nominal impulse impulse discharge discharge current current 8/20μ μ s 10/1000μ μs idi idi (KA) (A) Nominal Alternating discharge current at 50Hz, 1s ida (A) Nominal dc spark-over voltage Gas Discharge Tube dc spark-over voltage Impulse spark-over voltage at 1kV/μ μs Vsdc (V) Vsdc (V) Vsi (V) 72B75/L 75 60~90 ≦700 50 72B90/L 90 72~108 ≦700 50 72B150/L 150 120~180 ≦700 50 72B230/L 230 184~276 ≦800 100 72B250/L 250 200~300 ≦800 100 72B300/L 300 240~360 ≦900 72B350/L 350 280~420 ≦900 100 72B400/L 400 320~480 ≦1000 100 72B420/L 420 336~504 ≦1100 100 72B470/L 470 376~564 ≦1100 100 72B600/L 600 480~720 ≦1500 150 Part No. 10 100 10 Insulation resistance Ris (Ω Ω) V (V) 100 Capacitance at 1kHz C (pF) 9 ≧10 ≦3 72BXXX Series 72BXXXL Series Series W3 W4 72B ψ8.0±0.2 ψ8.0 +0.2 L3 L4 L5 1.5±0.1 10.0±0.3 4.25±0.15 -0.1 Series W3 72BL ψ8.0±0.2 W4 W5 L3 L4 L5 L6 L7 L8 15.0±0.5 1.5±0.1 10.0±0.3 4.25±0.15 13.4 -2 4.4±0.3 ψ1.0±0.1 +0.2 ψ8.0 -0.1