FB_BA_LightGroupConstant

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) with constant light regulation and manual override.

Function

If fully automatic is set via the parameter eLightActivationMode, the light function ConstLgtCtrl switches to control mode when presence is detected at the input bPresence. However, if semi-automatic is selected, the first press of a button on the template bManualSwitch will set the function block to control mode. Further button presses or a value specification via the HMI (fSetLightValueMan_In / SetLightValueMan_In) abort the control mode and the function block is in manual override.

In this mode, the light can be switched on and off alternately via the template input bManualSwitch or dimmed up and down with a long keystroke (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.

The light control block displays its current state "Control mode" or "Manual override" at the outputs bControlMode and bManualMode; both outputs are not set simultaneously. These outputs are used either to generate a light output telegram with the priority eAutomaticLight via the CnstLgtAuto function block 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, a HMI can be used to display a distinction between control mode and manual override.

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

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

Here, stArea represents the resulting telegram from the higher-level, higher-order 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).

The setpoint for constant light regulation is set using an analog object SpBrightness.

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_LightConstCtrl (internal function block). The use of the following variables is visible in this template:

• bSetLightValueMan_In: Command to switch to manual mode.
• fSetLightValueMan_In: Light value to be adopted.
• bSetCtrlMod_In: Command to switch to constant light control mode.
• eLightActivationMode_In: Activation mode of the light control function from the HMI (fully automatic or semi-automatic). The mode selected via the HMI is saved persistently.
• fLightValue_Out: Output of percentage light value to the HMI.
• bLightOn_Out: Output information "Light On" to the HMI.
• bErr_Out: Output information "Reference actuator faulty" to the HMI.
• eActualPrio_Out: Currently controlling telegram priority to the HMI.
• bCtrlMod_Out: Output information "Light function is in control mode" to the HMI.

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

Block diagram

Syntax

FUNCTION_BLOCK FB_BA_LightGroupConstant EXTENDS FB_BA_Ext_LightConstCtrl
VAR_INPUT
  bManualSwitch          : BOOL;
  bOn                    : BOOL;
  bOff                   : BOOL;
  bResetRoomFunction     : BOOL;
  bPresence              : BOOL;
  fBrightness            : REAL;

  stAreaLighting         : ST_BA_Lighting;
  stScene                : ST_BA_Lighting;
  stReferenceFeedback    : ST_BA_LightActuatorFeedback;
END_VAR
VAR_OUTPUT
  stLighting             : ST_BA_Lighting;
  bAdjusting             : BOOL;
END_VAR
VAR_INPUT CONSTANT PERSISTENT
  fHys                   : REAL;
  nSwiOvrTi              : UDINT;
  nSwiTi                 : UDINT;
  nDimTi                 : UDINT;
  nRampTi                : UDINT;
  nPreOffRampTi          : UDINT;
  nBrtnsAdjTi            : UDINT;
  fOnValCtrl             : REAL;
  fOnValMan              : REAL;
  fPreOffVal             : REAL;
  nPreOffDly             : UDINT;
  fMinVal                : REAL;
  nMinOffDly             : UDINT;
  nMinOnDly              : UDINT;
  bMemoryMode            : BOOL;
  fLgtT                  : REAL;
END_VAR
VAR_INPUT CONSTANT
  SpBrightness           : FB_BA_AV_Op;
  ManMode                : FB_BA_LightingEvt := ( ePrio := E_BA_LightingPrio.eManual);
  CnstLgtAuto            : FB_BA_LightingEvt := ( ePrio := E_BA_LightingPrio.eAutomaticLight);
END_VAR
VAR
  ConstLgtCtrl           : FB_BA_LightCtrlConst;
  PrioSwi                : FB_BA_LightingTgmSel4;
END_VAR