This paragraph provides the basic information if any problems occur during the
start-up procedure. In case the problem cannot be solved, contact the service
After closing RCB the LCD display is still blank
Check the phase rotation of supply voltage.
Make sure the input voltage and frequency are within tolerance.
Check the rectifier protection fuses F1-F2-F3; that they are inside
After step #1 the UPS stops the starting sequence and shows
one or more alarm messages
Check the alarms indicated on the display and remove their
Close RCB and try to restart the UPS.
After step #2 the unit shows the alarm A15 – Byp fault
Make sure you have closed circuit breaker SBCB.
Check the protection fuses of the static bypass switch;
they are inside the unit.
Check the phase rotation of the bypass voltage.
Make sure voltage and frequency are within tolerance.
After step #3 the unit shows the alarm A7 – BCB open
Make sure you have closed the battery circuit breaker; the
external circuit breaker or the fuse carrier that is external to the
Check the battery fuses.
Check the interconnection between the auxiliary contact of the
battery circuit breaker (in the external cabinet) and the terminals
Bac1-Bac2 of the UPS.
The control logic checks that all the output
parameters (voltage, current, frequency)
are correct. LED #7 is lit green: output
The default screen is displayed after a
short time with the UPS name and the