What you will see

  • Inverter will not start after rain or fog
  • Error 203 clears by late morning
  • Error 203 stays on dry days

Why it happens

Water in a connector or DC breaker, a cracked cable, rodent damage or a damaged panel lowers insulation to earth.

The inverter checks this before every start and will not connect until it is safe.

Diagram

Damp morning, weak insulation

Dry day

Panels and cablesWell insulated
→
InverterStarts

After rain or fog

Wet DC breaker or connectorLeaks to earth
→
InverterWaits, Error 203

If Error 203 stays on dry days, there is likely damage to find.

Applies to Growatt MIN, MOD, MID and SPH inverters.

What you can check yourself

  • Note whether it only happens on wet or foggy days
  • From a safe position, check whether the DC breaker box looks wet or open to rain
  • Look for cables lying in water or chewed

What not to do

  • Do not open the DC breaker box or unplug MC4 connectors
  • Do not spray water on cables to test

When to call us

  • Insulation test each string
  • Check earthing of frames and inverter
  • Dry or replace wet breakers and connectors

Monsoon and fog

Isolation faults rise across Punjab in the monsoon and on foggy Lahore and Faisalabad mornings. We test each string to find the wet or damaged part.

Send us

photos of the alarm, weather at the time, and the DC breaker box