Many of its functions have been adapted to fulfil the requirements of the EN 746 standard, for example:
- High-temperature supervision in conjunction with a safety limit thermostat (SLT) instead of the traditional flame supervision,
- Separate flame supervision with two flame detectors,
- Adjustable safety times up to 10 s according to EN746-2,
- Repetition, if there is no flame at the end of the safety time,
- Cooling function in standby mode,
- Very long postpurge times.
With the LMV50, it is now possible to integrate external flame safeguards. This ensures that the burner operates correctly in the event of unfavourable flame ratios. The new functions that have been added to the LMV50 system are particularly useful in applications involving regenerative and thermal exhaust air purification. The electronic fuel/air ratio control system replaces pneumatic gas/air control systems here. This ensures an independent ignition position and safe operation across all capacity ranges.
Together with the VGD/SKP gas valves, the LMV5 system is suited to use in safety-related systems up to SIL3. It can be integrated into the process control technology using digital bus technology or in parallel using standard signals. There are verified modules available for the SIMATIC products.
(Source: Siemens AG)