What is the purpose of a burner management system (BMS) interlock?

The purpose of a burner management system (BMS) interlock is to ensure the safe and reliable operation of the boiler by preventing unsafe conditions and automatically shutting down the burner if any hazardous situations are detected. Interlocks are safety devices or logic controls that prevent a system from starting or continuing to operate if certain conditions are not met. In a BMS, interlocks monitor critical parameters and automatically shut down the burner if these parameters deviate from safe operating limits. Common BMS interlocks include: 1) Low water level: This interlock shuts down the burner if the water level in the boiler falls below a minimum safe level, preventing damage to the boiler tubes. 2) High steam pressure: This interlock shuts down the burner if the steam pressure exceeds a maximum safe level, preventing over-pressurization and potential explosions. 3) Flame failure: This interlock shuts down the fuel supply if the flame is extinguished, preventing the accumulation of unburned fuel in the furnace, which could lead to an explosion. 4) Low fuel pressure: This interlock shuts down the burner if the fuel pressure falls below a minimum level, ensuring that the fuel is being supplied at the correct rate for stable combustion. 5) High furnace pressure: This interlock shuts down the burner if the furnace pressure exceeds a maximum level, preventing damage to the furnace structure. 6) Airflow proving: This interlock ensures that adequate airflow is established before the burner is ignited, preventing fuel-rich conditions and potential explosions. BMS interlocks provide a critical layer of safety, protecting the boiler and personnel from hazardous situations. They are designed to automatically respond to abnormal conditions, preventing potentially catastrophic events.