Siemens LMV50 Series Manual

Also see for LMV50 series: Manual Operating instruction

109/327Building Technologies Basic Documentation LMV5... CC1P7550en7 Boiler controller / load controller 22.05.20187.4.2 Modulating controlWhen selecting Gas, the LMV5 will automatically operate in modulating mode. For thisreason, parameterization is not required when firing on gas.When selecting Oil, the operating mode is to be set to modulating, if required, usingparameter Operation Mode of the electronic fuel-air ratio control system.In this operation mode, the load controller calculates the manipulated variable bymeans of a PID algorithm, depending on the control deviation.Example 1: The load is very small so that the controller must switch to ON/OFF mode.Setpoint Actual value7550f07E/0502R=ONY=OPENY=CLOSEDWSD_ModOffSD_ModOnFigure 53: Modulating control – function diagram example 1Example 2: The load is greater than the amount of heat produced by the burner underlow-fire conditions, thus enabling correct modulating operation.Setpoint Actual value7550f08E/0502R=ONY=OPENY=CLOSEDWSD_ModOffSD_ModOnFigure 54: Modulating control – function diagram example 2GeneralFunction diagrams