If the level exceeds or drops below a switchpoint, the cut-out circuit is interrupted and locked (LW), or the pump is shut down (HW).
The water level is controlled within the range of two fixed (conductivity method) or variable (capacitance method) switchpoints. The signals are forwarded directly to the feedwater pump or a valve.
The water level is continuously measured and compared with the set point in a controller. In the event of deviations, the flowrate is corrected by a control valve or a speed-regulated pump. This process enables steam boilers to be operated more gently and cost efficiently.