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Input Cnf FaultSolaX Power · SolaX X1-Hybrid G3

Input Cnf Fault on a SolaX Power SolaX X1-Hybrid G3: PV panel connection abnormal - check the two MPPTs are not connected in parallel

Short answer

On a SolaX Power inverter, Input Cnf Fault means: PV panel connection abnormal - check the two MPPTs are not connected in parallel. The inverter stops until the fault clears or is reset. An engineer is needed to fix the cause.

Reviewed 24 September 2026 · 1 source

What it means

The manual says: PV panel connection abnormal - check the two MPPTs are not connected in parallel.

Part involved: PV input over-voltage.

Likely causes:

  • As described in manual.

Is it safe?

Switch the inverter off at its isolator and call an engineer.

Does the inverter stop?Yes
SeveritySafety lockout
Engineer needed?Yes

The inverter stops until the fault clears or is reset.

Resetting itself: no.

Manual reset: yes, after string design is corrected.

What you can check

  • Read and note the exact code and time from the inverter display or app (screenshot).
  • Call the installer. Do not touch DC cabling.
  • Where the SolaX manual says 'press the ESC key to restart the inverter', a homeowner can do that on the display. Steps that say 'disconnect PV+/PV-/battery' are for the installer only.

What the engineer will check

  • Measure open-circuit string voltage (cold-weather Voc rise).
  • Check string design against inverter max DC voltage.
  • Check for mixed/incorrect module counts.

Who to ask for: PV installer / system designer.

Certification: Electrician competent in grid-connected PV (BS 7671 Section 712; IET Code of Practice for Grid-connected Solar PV), ideally the original MCS-certified PV installer; brand-approved/trained installer to keep manufacturer warranty.

What you might notice

Sources

A code explains what the controller detected, not a confirmed root cause.

Reviewed: 24 September 2026