Njoy Astris 5K/3P2T2 User Manual page 20

WARNING
According to regulations,the secondary protection grounding can't
replace the PE terminal connection of the AC cable. Ensure that
both are grounded reliably. Otherwise,fatal injury can occur due to
the high voltage.
CAUTION
If the positive pole or negative pole of the PV array is required to be
grounded, then the inverter output (to AC grid) must be isolated by
transformer in accordance with IEC63109-1,-2 standards.
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