FB_DALI_Tridonic_PCell_SSI_31_PC_DA2_SA

The function block represents the DALI light sensor PCell SSI 31 PC DA2 SA from Tridonic.

This outputs four brightness values (instances 0 to 3).

For information on the exact functions of the individual instances, please refer to the vendor's device documentation.

Further information on the supported instance types can be found here:

Part 304 (light sensors) - Introduction

The existing parameters can be overwritten by changing the properties listed below. All parameters are written to the DALI control device by a positive edge at bInitialize and stored there.

The outputs with the output values of the DALI device only contain valid values if the function block was executed without errors (bError = FALSE). If the output bError = TRUE, the outputs with the output values must not be evaluated.

The reading of the corresponding instance can be triggered immediately via the input variable bQueryBrightnessN, even if the corresponding instance is not enabled.

	Set the times so that as few events as possible are sent. If too many events are sent, this can have a negative effect on the behavior of the application.

	The function block cannot be used when using the KL6811.

Inputs

VAR_INPUT
  bInitialize                 : BOOL  := FALSE;
  nShortAddress               : BYTE  := 0;
  nOptions                    : DWORD := 0;
  bQueryBrightness1           : BOOL  := FALSE;
  bQueryBrightness2           : BOOL  := FALSE;
  bQueryBrightness3           : BOOL  := FALSE;
  bQueryBrightness4           : BOOL  := FALSE;
END_VAR

Name	Type	Description
bInitialize	BOOL	The configuration of the DALI control device is started by a positive edge at this input. During this time no DALI commands are processed.
nShortAddress	BYTE	Short address (0…63) of the DALI control device.
nOptions	DWORD	Reserved for future extensions.
bQueryBrightnessN	BOOL	The brightness is queried immediately by a positive edge at this input.

Outputs

VAR_OUTPUT
  bError                     : BOOL;
  ipResultMessage            : I_TcMessage;
  bInitializing              : BOOL;
  bReadingBrightness1        : BOOL;
  bReadingBrightness2        : BOOL;
  bReadingBrightness3        : BOOL;
  bReadingBrightness4        : BOOL;
  nBrightnessLevel1          : UINT;
  nBrightnessLevel2          : UINT;
  nBrightnessLevel3          : UINT;
  nBrightnessLevel4          : UINT;
END_VAR

Name	Type	Description
bError	BOOL	This output is switched to TRUE if an error occurs during the execution. Further information about the error can be queried via the variable ipResultMessage. The output is set to FALSE again as soon as bBusy switches to TRUE.
ipResultMessage	I_TcMessage	Interface pointer (see error evaluation) that can be used to obtain detailed information about the processing of the function block (see runtime messages). The interface pointer is valid after bBusy has changed from TRUE to FALSE.
bInitializing	BOOL	The output is set as soon as the initialization of the DALI control device has been started, and remains active until all DALI commands have been executed.
bReadingBrightnessN	BOOL	The output is TRUE as long as values of the instance of the light sensor are being read by the DALI control device.
nBrightnessLevelN	UINT	Measured brightness value of the light sensor.

	This measured value must be compared with the measured reference values at the place of operation of the DALI control device.

Properties

All parameters that are written to the DALI control device via bInitialize are available as properties.

The properties of instances of the same type are listed only once in the table and marked with N at the end.

Name	Type	Access	Initial value	Description
bEnableBrightnessN	BOOL	Get, Set	TRUE	TRUE at this property enables the instance for brightness measurement. FALSE on this property causes sending of events from this instance to be disabled. However, the actual value of the instance can still be queried via the input bQueryBrightnessN.
eEventPriorityBrightnessN	E_DALIEventPriority	Get, Set	MiddleLow	Setting of the event priority.
nReportTimerBrightnessN	BYTE	Get, Set	30 s	Time (0…255 s) after which the pending event of the light sensor is repeated if no other event has occurred in the meantime.
nDeadtimeTimerBrightnessN	UINT	Get, Set	1500 ms	Dead time (0...12750 ms) to ensure that not too many events are sent in succession. An event is only sent after expiry of the dead time timer. The dead time timer is restarted each time after an event has been sent.
nHysteresisBrightnessN	BYTE	Get, Set	5 %	Value (0…25 %) for calculating a hysteresis value in order to prevent frequent and disturbing changes when measuring the brightness.
nHysteresisMinBrightnessN	BYTE	Get, Set	255	As the percentage hysteresis can also lead to large fluctuations at low brightness, a minimum hysteresis can be specified via this property. The minimum hysteresis is an absolute value with a range from 0 to 255.
ipDALICommunication	I_DALICommunication	Get, Set	0	Interface pointer to the communication block (see Transfer of the reference to the communication block).

Requirements

Development environment	Required PLC library
TwinCAT from v3.1.4024.64	Tc3_DALI from v3.20.3.0