Mechanical details: 1) Dimensions (mm): a) Single lamp ballast: 320 x 30 x 30, 235 x 30 x 25 b) Twin lamp ballast: 320 x 30 x 30, 235 x 30 x 25 c) 3 / 4 lamp ballast: 320 x 30 x 30 2) Weight ( grms): a) Single lamp ballast: 320, 200 b) Twin lamp ballast: 350, 200 c) 3 / 4 lamp ballast: 380 3) Operating frequency: approx. 28 - 35 or 35 - 43kHz for all models 4) Ambient temperature / tc max.: -15°C to 50°C / 70°C 5) Suitable for Dc operation from 154V to 264V, Lamp(s) must be ignited at > 198V DC 6) Permitted maximum case temperature should not be exceeded 7) The cable length of any single cable between the ballast and the lamp must be less than 1.5 m Features: 1) Preheat start 2) Fuse, surge, open and short circuit of lamp protection 3) Automatic ballast cut-off in the event of detective lamp 4) Auto-starting of lamp when charging aging lamp