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USER MANUAL
8
The diagram below shows the LDX-U20 behavior when Shutdown and automatic restart is enabled.
Figure 5. Shutdown and restart chart
PARAMETER
NAME
DESCRIPTION
E1
Backup
Power failure on the line happens. System enters backup mode.
E2
Automatic PC shutdown
The POWERMASTER sends a shutdown command to the PC. Optionally: a task is called before
shutdown.
This event is triggered by the “PC shutdown delay” (§5.2.23) or “Battery low alarm” (§5.2.8),
whatever comes first.
E3
Unexpected PC shutdown
The PC shutdowns in an unexpected way, for example caused by OS crash.
E4
PC restart
LDX-U20 detect the PC being OFF because the output current was lower than Ioff current
threshold for T4 time. As a consequence LDX-U20 generates an ON->OFF->ON cycle on its
output.
T1
PC shutdown delay
User settable (§5.2.23). Time between start of backup and start of PC shutdown procedure.
T2
PC shutdown time
User settable (§5.2.24). Time between start of shutdown procedure and output voltage OFF.
This time must be set longer than the maximum time the PC takes to complete the shutdown.
T3
PC restart minimum OFF time
User settable (§5.2.25). T3 is the delay used between the return of the input voltage and the
activation of the output. The same time is used by the automatic restart function as power OFF
time to restart the PC. The value must be big enough for the PC to detect the supply
ON->OFF->ON cycle to restart.
T4
PC OFF detection timer
User settable (§5.2.27). Minimum time at which the output current must be below the Ioff current
threshold to trigger the automatic PC restart (PC supply ON->OFF->ON cycle).
Ioff
PC OFF detection current
threshold
User settable (§5.2.26). Current threshold used to detect PC OFF status. This value must be
lower than the minimum PC current consumption when this is ON.
Table 2. Shutdown and restart
The parameters are settable through the LDX-U20 LCD or using the POWERMASTER application. The checkbox “Run on startup” must be
checked on POWERMASTER when PC shutdown function is used, select “Start in tray” to start in minimized into the windows system tray.
To inhibit the software from calling the shutdown command user can select the “Inhibit shutdown” check box.