Bender ATICS Series, Manual

Page: 16 / 104

16 ATICS-DIO_D00080_03_M_XXEN / 04.2021
System description
2. The ATICS® switches from the redundant line back to the preferred line if
– the voltage on the preferred line is restored and the return transfer delay time t(2->1) has
elapsed and no switch-back lock is enabled
– or immediately after pressing the "RESET" button or when the redundant line fails (even when
the switch-back lock is enabled)
– the setting "Preferred line" is changed to the other line
– the digital input is configured to "TEST" and this input is reset
– a test of the automatic transfer switching device is active and the test period has elapsed
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W
arning
!
Malfunction possible if delay times are not adjusted.
The response delay t(on), the return transfer delay time t(2->1), the delay on release t(off) and the
dead time t(0) of the ATICS® are adjustable and must be adjusted to the requirements of the specific
case, the short-circuit calculation and the requirements of DIN VDE 0100-710 (VDE 0100-710) for au-
tomatic transfer switching devices (see chapter „Commissioning, settings and testing“ auf S. 43).
The factory settings guarantee a changeover period of t ≤ 0.5 seconds and switching back within 10
seconds when voltage is restored on the preferred supply. Therefore, the ATICS® can be used in IT sys-
tems with a requirement for a changeover period t ≤ 0.5 s (IT systems with operating theatre lights, en-
doscopic field illumination in operating theatres or other essential sources of light, etc.).
When there is a short circuit downstream of the automatic transfer switching device, the automatic
transfer switching device must not continually change back and forth between the two lines. This can
occur if the short-circuit current is small and the automatic transfer switching device switches faster
than the short-circuit breaker trips. The ATICS® monitors the load current downstream of the automatic
transfer switching device in order to detect a possible short circuit. If the preferred line fails and a
short-circuit current is detected at the same time, the ATICS® does not switch over immediately but
only once the circuit breaker has tripped.
If the ATICS® detects a supply failure or a fault, an alarm appears on the LCD, the "ALARM" LED lights up,
the alarm relay trips (if set) and this alarm is forwarded to other Bender devices (such as an alarm indi-
cator and test combination) via the BMS bus.
Phase sequence direction errors are detected and indicated on the LC display. Even so ATICS® switches
over to the redundant line.