====== Two-stage Source (v2.0) ======

{{:cs:mervis-ide:35-help:twostagesource.png}}

==== Full Name ====

Lib.Mervis.v2_0.TwoStageSource

===== Description =====

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

==== Required Project References ====

  * Lib.Mervis

===== Usage in ST =====

<code>
program test
    var
        twoStageBoiler: lib.mervis.v2_0.TwoStageSource;
    end_var

    twoStageBoiler();
end_program
</code>

===== Description of Inputs and Outputs =====

|Inputs                  |Name                                                        |Data Type|Retain|Required Connection                                                                                    |Meaning|
|OperatingMode           |[[..:..:operatingmodetype.htm|Lib.Mervis.v1_0.OperatingModeType]]|Yes      |No    |Source operating mode                                                                                 |      |
|PumpOperatingMode       |[[..:..:operatingmodetype.htm|Lib.Mervis.v1_0.OperatingModeType]]|Yes      |No    |Circulation pump operating mode                                                                       |      |
|ManualPower             |real                                                         |Yes      |No    |Source power in manual mode                                                                           |      |
|Output                  |real                                                         |No       |Yes   |Controlled variable                                                                                   |      |
|Demand                  |[[..:..:stagecontroltype_v2.0.htm|Lib.Mervis.v2_0.StageControlType]]|No       |Yes   |Combined demand from the [[..:..:cascadecontroller_v2.0.htm|cascade controller]]                       |      |
|Feedback                |bool                                                         |No       |No    |Feedback signal of source operation                                                                   |      |
|Failure                 |bool                                                         |No       |No    |Feedback signal of source failure                                                                     |      |
|PumpFeedback            |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)                  |      |
|LimitForAttach          |real                                                         |No       |No    |Limit value of the [[..:..:integralcriterion.htm|criterion]] for activating the second stage            |      |
|LimitForDettach         |real                                                         |No       |No    |Limit value of the [[..:..:integralcriterion.htm|criterion]] for deactivating the second stage          |      |
|MaxOutput               |real                                                         |No       |No    |Maximum value of the controlled variable, exceeding it is considered a fault                          |      |
|FeedbackTimeout         |time                                                         |No       |No    |Interval waiting for active source operation feedback                                                 |      |
|FailureCountLimit       |uint                                                         |No       |No    |Number of consecutive source errors before it is permanently marked as non-functional                 |      |
|FailureDelay            |time                                                         |No       |No    |Time after an unsuccessful source start before retrying                                               |      |
|MinimalRunTime          |time                                                         |No       |No    |Minimum time the source will be kept running                                                          |      |
|MinimalStopTime         |time                                                         |No       |No    |Minimum time before the source is restarted                                                           |      |
|KeepCommandWhileFailure |bool                                                         |No       |No    |Determines whether the operation command remains active even in case of a fault                       |      |
|UseLocalOutput          |bool                                                         |No       |No    |Determines whether the control uses the common output or its own (= true)                             |      |
|PumpRunDown             |time                                                         |No       |No    |Run-down time of the circulation pump after the source is removed from the cascade                    |      |
|PumpFeedbackTimeout     |time                                                         |No       |No    |Interval waiting for active circulation pump operation feedback                                       |      |
|PumpNotRunAlarmPriority |[[..:..:..:alarms_alarmprioritytype.htm|AlarmPriorityType]]     |No       |No    |Priority of the circulation pump not running fault                                                    |      |
|PumpFailureAlarmPriority|[[..:..:..:alarms_alarmprioritytype.htm|AlarmPriorityType]]     |No       |No    |Priority of the circulation pump failure                                                              |      |


|Outputs           |Name                                                        |Data Type                                                                                         |Meaning|
|State             |[[..:..:stageinfotype_v2.0.htm|Lib.Mervis.v2_0.StageInfoType]]|Combined source state to the [[..:..:cascadecontroller_v2.0.htm|cascade controller]]                       |      |
|Command1          |bool                                                         |Command for operating the first stage                                                             |      |
|Command2          |bool                                                         |Command for operating the second stage                                                            |      |
|PumpCommand       |bool                                                         |Command for the circulation pump                                                                  |      |
|RunTimeInHours    |udint                                                        |Source runtime in whole hours                                                                     |      |
|PumpCompositeState|udint                                                        |Bit field describing the state of the circulation pump (see [[..:..:switcherblock_v2.0.htm|SwitcherBlock v2.0]])|      |


|Blocks      |Name                                                         |Data Type                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |Meaning|
|PumpControl |[[..:..:switcherblock_v2.0.htm|Lib.Mervis.v2_0.SwitcherBlock]]|Control of the circulation pump                                                                                                                                                                                                                                                                                                                                                                                                                                                          |      |
|Alarms      |[[..:..:alarmsextender4.htm|Lib.Mervis.v1_0.AlarmsExtender4]] |Alarm function block\\ \\ |Alarm Input|[[..:..:alarmspriorities.htm|Priority]]|Meaning                              |\\ |Alarm1        |33                               |Source failure                        |\\ |Alarm2        |-                                |Not used                            |\\ |Alarm3        |33                               |Exceeding maximum output value       |\\ |Alarm4        |-                                |Not used                            ||      |


===== Detailed Function Description =====

TODO

===== Usage Example =====


===== Versions =====

{{indexmenu>.020-twostagesource#2}}