Grundfos Multifit MD Series Installation And Operating Instructions Manual page 15

If a fault occurs, the red LED will flash, the symbol will be
visible and the fault will be added to the fault log.
Furthermore,Hthe buzzer will be activated, the symbol will be
visible, the corresponding symbols will flash and the fault code
will be displayed. When the fault has disappeared or has been
removed, the controller will automatically switch to normal
operation again. However, the controller enables resetting of the
fault indication (visible and acoustic alarms) either manually
(Man) or automatically (Auto).
If manual resetting was selected in setup menu, the acoustic
alarm and red LED can be reset by pressing the button .
The fault indication will be reset when the fault has disappeared,
has been removed or the ON-OFF-AUTO switch has been set to
OFF position.
You can get an overview of faults in the fault log in information
menu.
The symbol will be visible as long as the fault log is open.
If automatic resetting was selected in menu setup, the red LED
and the symbol will disappear, and the buzzer will be
deactivated again after the fault has disappeared, has been
removed or the ON-OFF-AUTO switch has been set to OFF
position. However, even if automatic resetting was selected,
some of the fault indications have to be reset manually.
See the table above.
Every 30 minutes the fault indication will be written from the
short-term memory into the long-term memory.
Fig. 14 Changing phases of a three-phase controller with
phase inverter
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