128
Fault display
UAC_1
UAC_3
AC under/over-
voltage
Causes
The grid voltage is too low
or too high.
The cable cross-section in
the AC feed line to the solar
inverter is too small.
Your solar system feeds into
a spur line, which is inade-
quately dimensioned.
Remedies
The solar inverter monitors the limits of
the minimum and maximum permissible
3-phase grid voltage. If the values exceed
or fall below these limits (Umin = 184 V,
Umax = 264 V), the solar inverter swit-
ches off and only restarts automatically
when the voltage value has returned
within the limits. The fault cut-out can
be triggered even if the values only
exceed or fall below the limits very
briefly (up to ca. 1 ms).
Ask your electricity board about grid
stability and design.
Check the format of your grid connection
(energy counter) and the grid feed-in
point to your electricity board.