FancoilContinuous (FB)¶

FUNCTION_BLOCK FancoilContinuous

Controls a fan coil unit with continuous fan.

Application example¶

Fan coil units are widely used in building automation for decentralised room temperatur control and air quality control. Fan coil units can roughly be classified in:

2-pipe-units (central switch over heating supply / cooling supply) vs. 4-pipe-units (separate heating supply / cooling supply)
units with continuous fan vs. units with 3-stage fan
ceiling mounted units vs. floor mounted units
units without integrated controller vs. with integrated controller

Device examples¶

Arbonia Condiline Deckenkassetten https://www.arbonia.de/produkte/deckenprodukte/fan-coils/
Kampmann KaDeck https://www.kampmann.de/hvac/produkte/fan-coils/kadeck

Why does CODESYS Building Automation library contain a fan coil unit control strategy, even if some fan coil units come with integrated controller?¶

Lots of fan coil units are sold / installed “bare metal” without integrated controller. Quiet often even fan coil units with integrated controller are sold without a controller as an option. FancoilContinuous provides an implementation of control strategy for a fan coil unit with continuous fan to integrate (or copy, modify and integrate) in your application.

Functionality¶

FancoilContinuous provides a control strategy for a fan coil unit with continuous fan. The fan is controlled either by:

control signal inputs - the heat / cool valve position setpoints compute by SequenceControl
control deviation related to active operation mode (eModeIn)

The FancoilContinuous control strategy takes into account:

control of fan speed dependent on valve position or control deviation
separate non-linear characteristic curve of fan speed for heating / cooling
minimum fan speed
fan follow-up time
coil pre-heat / pre-cool
control of optional condensate pump (cooling mode)
manual control of fan
manual control of valves

Characteristic curve of fan speed¶

The fan can be controlled dependent on valve position or control deviation - default is dependent control deviation. Please be aware, that negative heating control deviation and positive heating control deviation should activate the fan. Usually a “dead zone” is supposed to be in between heating sequence and cooling sequence - for more details see SequenceControl. To setup the characteristic curve of fan speed for fan control dependent control deviation choose rFanScaleHeatX0..rFanScaleHeatX2 to appropriate heat deviation and associate rFanScaleHeatY0..rFanScaleHeatY2 appropriate fan speed. Set rFanScaleCoolX0..rFanScaleCoolX2 / rFanScaleCoolY0..rFanScaleCoolY2 accordingly for cooling. FancoilContinuous does a linear interpolation on those inputs to compute the “automatic” fan speed.

To setup the characteristic curve of fan speed for fan control dependent valve position choose rFanScaleHeatX0..rFanScaleHeatX2 with appropriate heat valve and associate rFanScaleHeatY0..rFanScaleHeatY2 appropriate fan speed. Set rFanScaleCoolX0..rFanScaleCoolX2 / rFanScaleCoolY0..rFanScaleCoolY2 accordingly for cooling.

InOut:

Scope	Name	Type	Initial	Comment
Input	`xEnable`	`BOOL`	TRUE	Enable
	`rHeatIn`	`REAL`		Heat control signal (0..100%).
	`rCoolIn`	`REAL`		Cool control signal (0..100%).
	`eModeIn`	HeatCoolOperationMode	HeatCoolOperationMode.UNUSED	Controller operation mode.
	`rDeviationMode`	`REAL`		Control deviation related to active operation mode - negative value for HEAT, positive value for COOL
	`xFanSpeedByDeviation`	`BOOL`	TRUE	Control fan speed dependent on control signal (FALSE) or control deviation (TRUE).
	`rFanScaleHeatX0`	`REAL`	0.0	Characteristic curve of fan speed for heating X0
	`rFanScaleHeatY0`	`REAL`	0.0	Characteristic curve of fan speed for heating Y0
	`rFanScaleHeatX1`	`REAL`	-1.0	Characteristic curve of fan speed for heating X1
	`rFanScaleHeatY1`	`REAL`	50.0	Characteristic curve of fan speed for heating Y1
	`rFanScaleHeatX2`	`REAL`	-2.0	Characteristic curve of fan speed for heating X2
	`rFanScaleHeatY2`	`REAL`	100.0	Characteristic curve of fan speed for heating Y2
	`rFanScaleCoolX0`	`REAL`	0.0	Characteristic curve of fan speed for cooling X0
	`rFanScaleCoolY0`	`REAL`	0.0	Characteristic curve of fan speed for cooling Y0
	`rFanScaleCoolX1`	`REAL`	1.0	Characteristic curve of fan speed for cooling X1
	`rFanScaleCoolY1`	`REAL`	50.0	Characteristic curve of fan speed for cooling Y1
	`rFanScaleCoolX2`	`REAL`	2.0	Characteristic curve of fan speed for cooling X2
	`rFanScaleCoolY2`	`REAL`	100.0	Characteristic curve of fan speed for cooling Y2
	`rFanMinSpeed`	`REAL`	0.0	Minimum fan speed (0..100%).
	`tFanFollowUp`	`TIME`	TIME#2m0s0ms	Fan follow-up time.
	`tFanFollowUpSpeed`	`REAL`	20.0	Fan speed during follow-up time (0..100%).
	`tPreHeat`	`TIME`	TIME#0ms	Coil pre-heat time.
	`tPreCool`	`TIME`	TIME#0ms	Coil pre-cool time.
	`xCpumpErri`	`BOOL`	FALSE	Condensate pump error indication - condensate pump is signaling an error
	`rHeatManual`	`REAL`	0.0	Heat valve manual control (0..100%).
	`xHeatManual`	`BOOL`	FALSE	Heat valve manual control used.
	`rCoolManual`	`REAL`		Cool valve manual control (0..100%).
	`xCoolManual`	`BOOL`	FALSE	Cool valve manual control used.
	`rFanSpeedManual`	`REAL`	0.0	Fan speed manual control (0..100%).
	`xFanSpeedManual`	`BOOL`	FALSE	Fan speed manual manual control used.
	`xReset`	`BOOL`	FALSE	Reset
	`itfDateTimeProvider`	`Util.IDateTimeProvider`	Globals.g_dtpDateTimeProvider	Source for the current date and time information in milliseconds since 1.1.1970 00:00:00.000
Output	`eModeOut`	HeatCoolOperationMode	HeatCoolOperationMode.INACTIVE	Operation mode.
	`rHeatOut`	`REAL`		Heat valve signal (0..100%).
	`rCoolOut`	`REAL`		Cool valve signal (0..100%).
	`rFanSpeedOut`	`REAL`	0.0	Fan speed (0..100%).
	`xCpumpOut`	`BOOL`	FALSE	Condensate pump.
	`xError`	`BOOL`		Error indication
	`eErrorID`	Error		Error ID