stertil-KONI ST 1055 Installation, Operation & Service Manual page 28

The control system controls the phase sequence and the presence of 3 phases during start-up. In the event
of a phase fault, the control buttons 3, 4 and 6 will flash alternately.
The microprocessor board is equipped with 4 LEDs for indicating failures; the order in which they are
lit indicates the type of defect as described in 8.2.
To see the LEDs open the control box cover.
Refer to fig. E and H for identification of components.
Fig. 8.1, Location of fault LED's
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MICROPROCESSOR
BOARD