The Tridonic 1/2x26-42 TC Pro is an energy saving long life lighting ballast, specifically designed for 4-pin compact fluorescent lamps. This lighting ballast can run 1 or 2 circular fluorescent lamp. This high frequency ballst has an average life of 50,000 hours. Key features: CELMA Energy Efficiency Index A2 BAT / A2 Nominal life-time up to 100,000 h (at ta 50 C with a failure rate 0.2 % per 1,000 h) Large temperature range (for values see table) Devices can operate either 1 or 2 lamps Intelligent Voltage Guard (overvoltage indication and undervoltage shutdown) Constant luminous flux irrespective of fluctuations in mains voltage For luminaires of protection class I and protection class II Automatic start after replacement of defective lamps Safety shutdown of defective lamps and at end of lamp life (EOL 2) For emergency lighting systems as per EN 50172 For luminaires with M and MM as per EN 60598, VDE 0710 and VDE 0711 Temperature protection as per EN 61347-2-3 C5e