FB_BA_LightGroupSwitchPresence

One or more light actuators are combined in a light zone for simultaneous control, depending on local conditions.

This template represents a light zone (room) that is operated both via switches and occupancy sensors.

Function

The light can be switched on and off alternately via the template input bManualSwitch using the control block LightSwitch or dimmed up and down with a long button press (t > SwiOvrTi).

The inputs bOn and bOff allow the light to be switched on and off selectively, while the light value fSetLightValueMan_In is set directly via a HMI using the bSetLightValueMan_In command.

If fully automatic mode is set via the parameter eLightActivationMode, the light switches on automatically when presence is detected at the input bPresence and switches off automatically on a falling edge. However, if semi-automatic mode is selected, the presence input is only used to switch off.

The light control block distinguishes whether it has been activated or overridden manually or by presence. In the first case, the output bAutomaticMode is set, in the second case bManualMode; both outputs are not set at the same time. These outputs are used either to generate a light output telegram with the priority eAutomaticLight via the function block AutoMode or a telegram with the priority eManual via ManMode. The different telegram priority is assigned to the internal HMI variable eActualPrio_Out on the PrioSwi function block. For example, an HMI can be used to display a distinction between automatic or manual/manual override.

On a falling edge at the template input bPresence or by setting bResetRoomFunction, the light control block is deactivated, whereby, if selected, it still announces its switch-off via a switch-off ramp with a dwell time at a pre-switch-off value. Both function block outputs bAutomaticMode and bManualMode are then deleted.

In addition to the internal telegrams from AutoMode and ManMode, the input-side stAreaLighting and stScene are also routed to the selector (PrioSwi).

Here, stArea represents the resulting telegram from the higher levels (area, floor and building), while stScene is reserved for any lighting scene to override the constant light regulation.

The telegram selector (PrioSwi) forwards the telegram with the highest priority - with the same priority, the last telegram sent (last writer wins).

Input stReferenceFeedback

Information about the controlled light actuator or the reference actuator of a group is fed back into the light control function via this input.

The light value of the reference actuator is of particular importance here: If the light actuator is already controlled by another function of the same or lower priority and the template described here now "takes over" control, it must control the actuator based on its existing light value.

In addition, current values and states are transmitted and can be displayed via the HMI.

Data exchange HMI

The data exchange with the HMI is realized here in the base class FB_BA_Ext_LightCtrl (internal function block). The use of the following variables is visible in this template:

• fSetLightValueMan_In: Light value to be set via the HMI.
• bSetLightValueMan_In: Command from the HMI that the above light value is to be set.
• bLightOn_Out: Output information "Light On" to the HMI.
• fLightValue_Out: Output information light value to the HMI.
• bErr_Out: Output information "Reference actuator faulty" to the HMI.
• eActualPrio_Out: Currently controlling telegram priority to the HMI.

The initialization of the template takes place within the method FB_Init.

Block diagram

Syntax

FUNCTION_BLOCK FB_BA_LightGroupSwitch EXTENDS FB_BA_Ext_LightCtrl
VAR_INPUT
  bManualSwitch           : BOOL;
  bOn                     : BOOL;
  bOff                    : BOOL;
  bResetRoomFunction      : BOOL;
  bPresence               : BOOL;
  stAreaLighting          : ST_BA_Lighting;
  stScene                 : ST_BA_Lighting;
  stReferenceFeedback     : ST_BA_LightActuatorFeedback;
END_VAR
VAR_OUTPUT
  stLighting              : ST_BA_Lighting;
END_VAR
VAR_INPUT CONSTANT PERSISTENT
  nSwiOvrTi               : UDINT;
  nSwiTi                  : UDINT;
  nDimTi                  : UDINT;
  nPreOffRampTi           : UDINT;
  fOnVal                  : REAL;
  fPreOffVal              : REAL;
  nPreOffDly              : UDINT;
  bMemoryMode             : BOOL;
  eLightActivationMode    : E_BA_LightActivationMode;
  fLgtT                   : REAL;
END_VAR
VAR_INPUT CONSTANT 
  ManMode                 : FB_BA_LightingEvt :=( ePrio:= E_BA_LightingPrio.eManual);  
  AutoMode                : FB_BA_LightingEvt :=( ePrio:= E_BA_LightingPrio.eAutomaticLight);
END_VAR
VAR
  LightSwitch             : FB_BA_LightCtrl;
  PrioSwi                 : FB_BA_LightingTgmSel4;
END_VAR