FB_S_UPS

FB_S_UPS 1:

The function block FB_S_Ups can be used on PCs with Seconds UPS, to communicate from the PLC with the UPS. The FB_S_Ups can be used to save persistent data and to QuickShutdown the PC in case of a power failure. The INPUTs of the FB_S_UPS should be used with the default values.

Note

Data loss

The Seconds UPS is only capable of holding the voltage for a few seconds. This is just enough time to save the persistent data. The used persistent saving mode must be "SPDM_2PASS", even though if this could causes realtime problems. The router memory must be big enough in order to save the persistent data!

Mode eSUPS_WrPersistData_Shutdown (default setting): The persistenten data are written and a QuickShutdown is automatically performed.

Mode eSUPS_WrPersistData_NoShutdown: Only the persistenten data are written, a QuickShutdown will not be performed.

Mode eSUPS_ImmediateShutdown: a QuickShutdown is immediatelly performed.

Mode eSUPS_CheckPowerStatus: only the powerfailure will be detected, no action is performed. In case of the powerfailure the FB waits until the tRecoverTime (10s) has expired before it goes back to the PowerOK state.

The UPS will switch off the main board after the capacitors have been discharged, independent of the mode and therefore independent of the writing of the persistent data and of the QuickShutdown, even if the power supply is restored.

The capacity of the UPS is to small to hold the system alive during longer power outages. The saving of the persistent data has to be done to the Compact Flash, since a hard disk cannot be operated if the UPS supplies the voltage. After the saving of the persistent data a QuickShutdown will be executed.

Note

Attention if files are modified:

If other applications or the PLC are keeping files open or write to files during a power failure, then these files can get corrupted, since the QuickShutdown immediately reboots the PC.

Note

Attention if using Windows XP embedded:

The EWF (Enhanced Write Filter) or the FBWF (File Based Write Filter) has to be activated in order to ensure the validity of the Windows XP embedded files on systems with a Seconds UPS.

In case of the EWF the TwinCAT\Boot folder needs to be located on a not protected partition (see in the registry: HKEY_LOCAL_MACHINE\SOFTWARE\Beckhoff\TwinCAT\System\BootPrjPath).
In case of the FBWF the TwinCAT\Boot folder needs to be excluded from the protection (see Beckhoff FBWF Manager, Exclusion Settings).

FUNCTION_BLOCK FB_S_UPS

VAR_INPUT

VAR_INPUT
    sNetID          : T_AmsNetId := '';           (* '' = local netid *)
    iPLCPort        : UINT := AMSPORT_R0_PLC_RTS1;    (* PLC Runtime System for writing persistent data *)
    iUPSPort        : UINT := 16#4A8;         (* Port for reading Power State of UPS, dafault 16#4A8 *)
    tTimeout        : TIME := DEFAULT_ADS_TIMEOUT;    (* ADS Timeout *)
    eUpsMode        : E_S_UPS_Mode := eSUPS_WrPersistData_Shutdown; (* UPS mode (w/wo writing persistent data, w/wo shutdown) *)
    ePersistentMode : E_PersistentMode := SPDM_2PASS; (* mode for writing persistent data *)
    tRecoverTime    : TIME := T#10s;          (* ON time to recover from short power failure in mode eSUPS_WrPersistData_NoShutdown/eSUPS_CheckPowerStatus *)
END_VAR

sNetID : AmsNetID of the PC.

iPLCPort : Port number of the PLC runtime system (AMSPORT_R0_PLC_RTS1 = 801, AMSPORT_R0_PLC_RTS2 = 811, AMSPORT_R0_PLC_RTS3 = 821, AMSPORT_R0_PLC_RTS4 = 831).

iUPSPort : Port number for reading the UPS-State (default value is 16#4A8).

tTimeout : Timeout for the execution of the QuickShutdown.

eUpsMode : eUpsMode defines, if persistent data need to be written and if a QuickShutdown needs to be executed.
The default value is eSUPS_WrPersistData_Shutdown, means with writing of the persistent data and then a QuickShutdown. See E_S_UPS_Mode.

ePersistentMode : Mode for the writing of the persistent data. Default value is SPDM_2PASS.

tRecoverTime : Time which will be waited after a power failure (in case of UPS modes without shutdown) to go back to the status PowerOK.
The tRecoverTime needs to be a little bit bigger than the maximum holding time of the UPS, since the UPS will shut off even if the power supply is restored.

VAR_OUTPUT

VAR_OUTPUT
    bPowerFailDetect  : BOOL;        (* TRUE while powerfailure is detected *)
    eState            : E_S_UPS_State;   (* current ups state *)
END_VAR

bPowerFailDetect : TRUE if a power failure is detected; FALSE if the power supply is sufficiant.

eState : internal state of the function block, for the values see E_S_UPS_State.

VAR_GLOBAL

VAR_GLOBAL
    eGlobalSUpsState : E_S_UPS_State;    (* current ups state *)
END_VAR

eGlobalUpsState : internal state of the function block as a global copy of eState, for the values see E_S_UPS_State.

Requirements

Development environment	Target plattform	Hardware	PLC Libraries to include
TwinCAT v2.11.0 Build 2016 or higher (R2)	PC (i386)	Second-UPS	TcSUPS.Lib