How do I fix MPPT Input Fault on a Solis?

Measure open-circuit voltage on each string individually. Both strings on same MPPT should be within 5% of each other Then: Check for shading, dirt, or panel fault on underperforming string

Solis

E013

MPPT Input Fault

MPPT channel fault — inverter detecting abnormal input on PV1 or PV2.

Common causes

String voltage mismatch between MPPT channelsOne string significantly underperforming

What to check

STEP 1

Measure open-circuit voltage on each string individually. Both strings on same MPPT should be within 5% of each other

STEP 2

Check for shading, dirt, or panel fault on underperforming string

Escalate if

String voltages balanced, no shading — possible MPPT hardware fault, contact Solis support

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