Siemens Flame Relay LFS1.11A2The Siemens LFS1. 11A2 is a 230V AC 50 60Hz flame safeguard or flame detector relay designed for supervising gas and oil flames in continuous operation applications, suitable for OEMs building flame monitoring into their products, including those that require SIL3 capable security levels. It uses ionization probes or photocells for oil flames and UV detectors for intermittent gas flame supervision, providing a contact closure to a PLC to signal flame