System behavior

The settings under Alarm configuration influence the system behavior of the Beckhoff Miniport driver and affect how long the UPS supports the devices connected to it, when notifications or the critical alarm are issued.

Short power failure: t_Batt <t_CA

Long power failure: t_Batt >=t_CA

Long power failure during operation (tBatt >=tCA)

The UPS service has been started and is active. During a long power failure, the UPS service irrevocably starts shutting down the system.

System behavior 2:

Short power failures during operation (tBatt <tCA)

The UPS service has been started and is active. Short power failures are bridged by the UPS. A shutdown through the UPS service is not initiated.

Power failure during the boot process

The UPS service is not yet active at this time. The UPS automatically switches to battery operation, thus bridging the power failure. The PC is booted up in battery mode. During a prolonged power failure, the UPS service takes over control after the start and starts shutting down the system.

Restoration of supply and repeated power failures during UPS shutdown

The following diagram shows a case in which the UPS service initiates a shutdown and the supply is restored during the shutdown.

Once the UPS service has initiated the shutdown this process cannot be stopped and must be completed. Repeated power failures during the shutdown are bridged by the UPS. In order to enable the IPC to restart the external power supply is interrupted briefly (a few seconds).

Value	Description	Properties
tBatt	Time during which the system is operated via the battery.	Variable, depending on the duration of the power failure. If tBatt >=tCA the UPS service irrevocably starts shutting down the system.
tCA	Maximum time on battery voltage before critical alarm. Once this time has elapsed the UPS service irrevocably starts shutting down the system.	Configurable in minutes (or in seconds starting from Windows 7 and higher) via the Beckhoff UPS configuration dialog. If tCA = 0 the UPS service immediately starts shutting down the system.
tSDtask	A time window provided by the UPS service for a shutdown application (shutdown task).	Not configurable, fixed and limited to a maximum of 30 seconds. NT4: tSDtask = 0 if no shutdown application was configured and tSDtask =tSDapp if a shutdown application was configured. All other operating systems:tSDtask always requires 30 seconds.
tSDapp	Time actually required by the shutdown application (shutdown task).	Variable, depends on the features of the application. Limited to a maximum of 30 seconds. After 30 seconds the shutdown continues irrevocably. tSDapp should always be < maximum oftSDtask.
tTCstop	This time is required for stopping the TwinCAT system. During this time the UPS service stops all TwinCAT servers.	Variable, depends on the number of configured TwinCAT servers. Limited to a maximum of 45 seconds. Shutdown continues irrevocably after 45 seconds. tTCstop = 0 if no TwinCAT is installed or was already stopped previously.
tUPSoff	Delay time for switching off the UPS. The actual shutdown of the operating system starts once the UPS service has completed all internal shutdown tasks. Once this time has started the operating system takes over control and continues with the shutdown (window applications and services including the UPS services are closed and the system is shut down completely). Once this time has elapsed the UPS irrevocably switches off the outputs and the IPC in order to save battery capacity.	Configurable via the Beckhoff UPS configuration dialog. The available values are hardware-specific. tUPSoff should always be >tSDwin.
tSDsrv	Time required by the UPS service for shutting down internal tasks.	tSDsrv =tSDtask +tTCstop
tSDwin	Time required by the operating system for a shutdown.	Variable, depends on the number of running applications that have to be closed.
tDlg	For systems without soft power-off functionality (e.g. NT4): Time during which the dialog: "It is now safe to turn off your computer" is displayed. For systems with soft power-off functionality (e.g. XP): With Beckhoff P24Vxxxx UPS: tDlg = 0, the UPS switches off the outputs and the IPC immediately. With APC-UPS: Time during the IPC continues to be supplied with UPS voltage (standby mode).	Variable, depends on the operating system used, the number of running applications, the motherboard and the UPS hardware: tDlg = tUPSoff -tSDwin tDlg should always be > 0. This value can only be influenced throughtUPSoff. For systems without soft power-off functionality the dialog should be visible at least for a short time before the UPS switches off the IPC. For systems with APC-UPS and soft power-off functionality the IPC should switch off first, followed by the UPS.
tBoot	Time required by the operating system during the boot process until the UPS service is started.	Variable, depends on the number of applications and services that have to be started.