> For the complete documentation index, see [llms.txt](https://support.powerio.com/hub/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.powerio.com/hub/codesys-hvac/en/hvac-library/functionblocks/components/burner3p.md).
# Burner3P
## `Burner3P` (FB)
FUNCTION\_BLOCK Burner3P
### Short description
> Control of a heat generator (temperature control via binary control commands More / Less)\
> \
> Typical application: heat generation
### Representation
### Functional description
#### General
This function block is used to control / regulate a heat generator depending on the demand of the heat generator *xEn*, the supply setpoint temperature *rSetPtTemp* and the supply temperature *rFdT*.\
The enabling / blocking of the heat generator is carried out via output *xHB* (FALSE = blocking, TRUE = enabling).\
The supply temperature control (analogously also boiler temperature control) is carried out by means of two power controllers (P controller, slow and fast) via outputs *xMoreHB* and *xLessHB*.\
Control enable is delayed (setpoint / parameter **udiWaitControl**) after the operating feedback (*xFb* = TRUE) of the heat generator.\
\
The following function blocks are mainly used:
ControlP
Out3P
OperatingHours
ManBin
#### Enabling / blocking of the heat generator
The enabling of the heat generator (*xAB* = TRUE, *xHB* = TRUE (eManModeB = eManBin.Auto)) occurs if the supply temperature *rFdT* the sum of supply setpoint temperature *rSetPtTemp* and setpoint / parameter **rSwitchOnPoint** falls below, while the general enable *xEn* is active (= TRUE) and the minimum off time is not active.\
The blocking of the heat generator (*xAB* = FALSE, *xHB* = FALSE (eManModeB = eManBin.Auto)) occurs if the supply temperature *rFdT* the sum of supply setpoint temperature *rSetPtTemp* and setpoint / parameter **rSwitchOffPoint** exceeds and at the same time the general enable *xEn* is active (= TRUE).\
Between two consecutive operating cycles, a minimum off time is always inserted (duration = **udiTimeMinOff**, display - remaining time: *tOnDelay*) inserted.\
The minimum off time begins with the falling edge (TRUE > FALSE) at input *xFb*.
#### Temperature control of the heat generator
Control enable is delayed (duration = **udiWaitControl**, display - remaining time: *tOnControlDelay*)\
after the active operating message (*xFb* = TRUE) of the heat generator.\
The blocking of temperature control occurs immediately after the inactive operating message (*xFb* = FALSE) of the heat generator (switch-off value: **rYDisabled**).\
The two internal power controllers (P controller, slow and fast, output range each -100.0 - 100.0 %) are enabled / blocked simultaneously. (Setpoint = supply setpoint temperature *rSetPtTemp*, actual value = supply temperature *rFdT*).\
The control signals of both power controllers are fed to the output controller in minimum value selection (forwarding the signal with the lower value) in the range -100.0 - 100.0 %.\
The output controller finally generates output signals for a 3-point actuator (pulse-width modulation, integration interval = **tIntegration**) with outputs *xMoreHB* or *xLessHB*.\
The constant pulse duration for the two outputs can each be freely set (**tImpulsOpen** or **tImpuls Close**), the variable pulse pauses are determined by the output controller.\
The two power controllers can be configured individually and independently of each other (fast P controller: gain factor **rKpBig**, slow P controller: gain factor **rKpTiny**).
#### Manual override of the digital outputs
All digital control outputs after manual override (*xHB*, xMoreHB\*, *xLessHB*) can be operated either in automatic mode (eMANBIN.Auto) or in one of the two manual operating modes (eMANBIN.ManOn, eMANBIN.ManOff).
| *xAB* | eMANBIN | *xHB* | Notes |
| ----- | -------------- | ----- | ----------------------------------------- |
| FALSE | eMANBIN.Auto | FALSE | manual override module in automatic |
| TRUE | eMANBIN.Auto | TRUE | manual override module in automatic |
| X | eMANBIN.ManOn | TRUE | manual override module in manual mode On |
| X | eMANBIN.ManOff | FALSE | manual override module in manual mode Off |
Legend: X = any
#### Collective fault *xAlarm*
The collective fault *xAlarm* is active (= TRUE) if the fault message of the heat generator *xAlarmIn* is active (= TRUE).\
In all other situations, the collective fault is *xAlarm* not active (= FALSE).
#### Collective message automatic mode *xAuto*
The collective message automatic mode *xAuto* is activated (= TRUE) if the following conditions are simultaneously met:
* Input *eAOO* = HVACTYPES.eManBin.Auto
* Input *eAOOMore* = HVACTYPES.eManBin.Auto
* Input *eAOOLess* = HVACTYPES.eManBin.Auto
* Setpoint / parameter **eManModeB** = eMANBIN.Auto
* Setpoint / parameter **eManModeBMore** = eMANBIN.Auto
* Setpoint / parameter **eManModeBLess** = eMANBIN.Auto
#### Operating hours counter - heat generator
The operating hours counter (*udiOperatingHours*, *udiCountFb*) for the heat generator is active when the operating message is active (*xFb* = TRUE).
> **Write access to the counter values**
>
> Via the path ‘InstanceName.\_OperatingHours.udiOperatingHours’ or ‘InstanceName.\_OperatingHours.udiCountFb’, write access to both counter values is possible.
>
> **Requirement for using the Burner3P function block**
>
> For correct operation, the TimeRead2 function block must be used.
#### Current calculated power of the heat generator *rPos*
The current **calculated power** of the heat generator is displayed at output *rPos* in the range 0.0 - 100.0 %.\
For this, the correct specification of the actuator runtime between minimum and maximum power (**tDuration**) is required.\
No repositioning takes place at a reference position.
#### Feedback of the heat generator power *rU*
The current **actual** power of the heat generator can be connected at input *rU* .\
This input is currently not used for control and regulation purposes.
#### Inactive state (*xEn* = FALSE)
| *xHB* | *xAB* | *xMoreHB* | *xMoreAB* | *xLessHB* | *xLessAB* | *rPos* | *tOnDelay* | *tOnControlDelay* | *dtLastFb* | *udiOperatingHours* | *udiCountFb* | *xAlarm* | *xAuto* | Notes |
| -------------------------------- | ----- | ------------------------------------ | --------- | ------------------------------------ | --------- | ------ | ---------- | ----------------- | ---------- | ------------------- | ------------ | ------------------- | --------- | ------------- |
| FALSE (eManModeB = eManBin.Auto) | FALSE | FALSE (eManModeBMore = eManBin.Auto) | FALSE | FALSE (eManModeBLess = eManBin.Auto) | FALSE | 0.0 % | old value | old value | old value | old value | old value | State of *xAlarmIn* | old value | *xEn* = FALSE |
Legend: X = any
### CODESYS
InOut:
| Scope | Name | Type | Initial |
| ----------- | ------------------- | ------- | ------------ |
| Input | `xEn` | `BOOL` | |
| Input | `rSetPtTemp` | `REAL` | |
| Input | `xFb` | `BOOL` | |
| Input | `rU` | `REAL` | 0 |
| Input | `xAlarmIn` | `BOOL` | |
| Input | `eAOO` | eManBin | eManBin.Auto |
| Input | `eAOOMore` | eManBin | eManBin.Auto |
| Input | `eAOOLess` | eManBin | eManBin.Auto |
| Input | `rFdT` | `REAL` | |
| Output | `xHB` | `BOOL` | |
| Output | `xAB` | `BOOL` | |
| Output | `xMoreHB` | `BOOL` | |
| Output | `xMoreAB` | `BOOL` | |
| Output | `xLessHB` | `BOOL` | |
| Output | `xLessAB` | `BOOL` | |
| Output | `rPos` | `REAL` | |
| Output | `tOnDelay` | `TIME` | |
| Output | `tOnControlDelay` | `TIME` | |
| Output | `dtLastFb` | `DT` | |
| Output | `udiOperatingHours` | `UDINT` | |
| Output | `udiCountFb` | `UDINT` | |
| Output | `xAlarm` | `BOOL` | |
| Output | `xAuto` | `BOOL` | |
| Input Const | `udiTimeTOFxFb` | `UDINT` | 7 |
| Input Const | `tDuration` | `TIME` | TIME#1m0s0ms |
| Input Const | `tIntegration` | `TIME` | TIME#100ms |
| Input Const | `tImpulsClose` | `TIME` | TIME#1s0ms |
| Input Const | `tImpulsOpen` | `TIME` | TIME#1s0ms |
| Input Const | `rKpTiny` | `REAL` | 0.6 |
| Input Const | `rKpBig` | `REAL` | 4 |
| Input Const | `rOffset` | `REAL` | 0 |
| Input Const | `rYDisabled` | `REAL` | 0 |
| Input Const | `udiWaitControl` | `UDINT` | 3 |
| Input Const | `rSwitchOffPoint` | `REAL` | 2.5 |
| Input Const | `rSwitchOnPoint` | `REAL` | -2.5 |
| Input Const | `udiTimeMinOff` | `UDINT` | 3 |
| Input Const | `eManModeBLess` | eMANBIN | eMANBIN.Auto |
| Input Const | `eManModeBMore` | eMANBIN | eMANBIN.Auto |
| Input Const | `eManModeB` | eMANBIN | eMANBIN.Auto |
---
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