Warning What does this mean?

Your system is down or running degraded, but this is not an immediate safety danger. Work through the safe steps below.

Growatt Inverter Error 100: Meaning, Causes & Safe Fix

Error 100 means the inverter's internal 2.5V reference voltage has failed — a core internal measurement circuit. The inverter cannot operate reliably and needs professional service.

What should I do first?

Two quick questions — we'll point you to the right starting point.

Is this code still showing on your inverter's display?

What this code means

Inside your inverter, a precise 2.5V reference voltage serves as the baseline for all internal measurements. Error 100 means this reference has failed, so the inverter can no longer trust its own readings and shuts down.

What is this downtime costing you?

Rough estimate while your system isn't producing. Adjust the numbers to match your setup.

System size (kW) Peak sun hours / day Electricity rate ($/kWh)

–per day

–per week

–per 30 days

≈ – kWh of lost production per day.

Estimate only — assumes ~80% real-world output vs. nameplate. Actual losses depend on weather, shading, panel direction, and your tariff.

Common causes

Internal voltage reference component failure
Control board fault
Age-related component degradation

Safe steps to try

Work top to bottom, ticking off each step as you complete it. 0 of 4 done.

Note the error code and when it appeared.
Perform one orderly restart: AC breaker off, DC switch off, wait 2–3 minutes, DC switch on, then AC breaker on.
If the error clears, monitor the system for 24 hours.
If it returns, stop restarting and call for service.

Is your inverter still under warranty?

Before paying for a repair, check — your installer may fix this free.

Brand Year installed

Based on typical standard warranty terms — always confirm with your warranty card or installer paperwork, as terms vary by model, region, and purchase date.

When to call an electrician

Call your installer or Growatt service if Error 100 persists after a restart — Growatt's official guidance states the inverter will need to be replaced. This is an internal hardware fault with no homeowner fix.

Frequently asked questions

What is the 2.5V reference?

It is an internal calibration voltage the inverter uses to measure everything accurately. When it fails, the inverter cannot verify safe operation, so it stops.

Can this be repaired, or do I need a new inverter?

Growatt's official troubleshooting says to contact service to replace the unit if a restart does not clear it — this is a board-level fault.

Is the rest of my system at risk?

No — the inverter fails safe by shutting down. Your panels and wiring are unaffected; only the inverter unit needs attention.

Need a professional?

This fault may need professional diagnosis. Contact a qualified solar electrician in your area.

Sources: meaning and troubleshooting verified against the manufacturer's documentation — Troubleshooting for Growatt TL&MTL (Ver1.2) 2013-7-15, Growatt New Energy ('it means the internal reference voltage fault. Restart the inverter, if the error still exists, please contact Growatt service to replace an inverter.')