Table of Contents

Modulated Boiler (v1.5)

Full Name

Lib.Mervis.v1_5.ModulatedBoiler

Description

Block used for controlling the performance of a boiler with a modulated burner and a circulation pump.

Required Project References

Usage in ST

program test
    var
        modulatedBoiler: lib.mervis.v1_5.ModulatedBoiler;
    end_var

    modulatedBoiler();
end_program

Description of Inputs and Outputs

Inputs Name Data Type RetainRequired Connection Meaning
OperatingMode Lib.Mervis.v1_0.OperatingModeType Yes No Boiler operating mode
PumpOperatingMode Lib.Mervis.v1_0.OperatingModeType Yes No Circulation pump operating mode
ManualPower real Yes No Boiler power in manual mode
OutputTemperature real No Yes Output temperature
BoilerDemand Lib.Mervis.v1_1.StageControlTypeNo Yes Combined boiler demand from the cascade controller
Running bool No No Feedback signal of boiler operation
Failure bool No No Feedback signal of boiler failure
PumpRunning bool No No Feedback signal of circulation pump operation
PumpFailure bool No No Feedback signal of circulation pump failure
ResetRuntime bool No No Reset runtime hours
MinimalOutput real No No External input for defining the minimum output temperature (if zero, it is not used)
Xp real No No PI controller - proportional band
Ti real No No PI controller - integral time
MaxOutputTemperature real No No Maximum output temperature, exceeding it is considered a fault
FailureDelay time No No Interval waiting for active boiler operation feedback
FailureCountLimit uint No No Number of consecutive boiler errors before it is permanently marked as non-functional
FailureTimeout time No No Time after an unsuccessful boiler start before retrying
LimitingXp real No No PI controller for limiting the maximum output temperature - proportional band
LimitingTi real No No PI controller for limiting the maximum output temperature - integral time
UseLocalOutputTemperaturebool No No Determines whether the control uses the common output temperature or its own (= true)
RunTimeSource Lib.Mervis.v1_0.RunTimeSourceType No No Determines how the boiler runtime hours are counted
PumpRunDownTime time No No Run-down time of the circulation pump after the boiler is removed from the cascade
PumpFailureDelay time No No Interval waiting for active circulation pump operation feedback
Outputs Name Data Type Meaning
State Lib.Mervis.v1_1.StageInfoType Combined boiler state to the cascade controller
Demand real Required boiler power
PumpDemand bool Command for the circulation pump
RunTimeInHours udint Boiler runtime in whole hours
FailureOutput bool Boiler fault
PumpFailureOutputbool Circulation pump fault
AlarmsStatus Lib.Mervis.v1_0.AlarmsStatus Combined interface for alarm indication
RunTime time Boiler runtime
Blocks Name Data Type Meaning
FailureFb Lib.Mervis.v1_0.FailureDetector Block for evaluating boiler failure
Alarms Lib.Mervis.v1_0.AlarmsExtender4 Alarm function block

Alarm InputPriorityMeaning
Alarm1 32/33 Boiler fault
Alarm2 - Not used
Alarm3 32 Pump fault
Alarm4 33 Boiler overheat

Detailed Function Description

TODO

Usage Example

Versions