The pressure-proof, fully enclosed combined ultraviolet/infrared flame detector enables UV and IR sensors to monitor the same detection zone with a visual angle of 90°. Triggering occurs only by activation of the IR and UV sensors. A LED provides information regarding the state of operation, failure and alarm. Three relays (fire, failure and additional alarm) are integrated for connection to a fire detection system. Contamination resistance and heated optics to prevent condensation and formation of ice also allow for external operation. Typical areas of application are turbines, munitions depots, natural gas depots and aircraft hangars. Monitoring on the loop and resetting via esserbus transponder 808623. Monitoring of a conventional line via the same transponder. This device requires a separate voltage supply of 24 V DC.