What does Growatt error 300 mean?
300 means the grid voltage is too low or too high, so the on-grid inverter stopped feeding power. When the voltage is normal again, the inverter restarts by itself.
Why does code 300 appear?
- The area's voltage is low or high.
- At midday many solar homes export together and push the line voltage up.
- The AC cable from inverter to meter is too thin or too long.
- A loose neutral or earth wire.
What can you safely check for 300?
- Wait a while. The inverter restarts by itself once the voltage is normal.
- Notice whether it happens daily at the same time (such as midday) or only sometimes.
Safety: never reach into an electrical panel, board, gas pipe or the inside of an inverter yourself. You can get a shock or release gas. This is a mistri's job.
When should you call a mistri?
If 300 shows every day, have a solar mistri check the AC cable size, connections and voltage. Only the installer should change grid settings. An inverter carries DC current from the panels and battery that can kill, even after the mains is off. Never open the inverter cover or the DC wires yourself.