Warning 401 on a Growatt inverter: Inverter communicates with Meter abnormal
Short answer
On a Growatt inverter, Warning 401 means: Inverter communicates with Meter abnormal. The inverter keeps running with some functions stopped. An engineer is needed to fix the cause. The wording differs by model range — each is shown below.
Reviewed 24 September 2026 · 2 sources
What it means
On the MIN 2500-6000TL-X
The manual says: Inverter communicates with Meter abnormal.
Part involved: Energy meter / CT clamp communication.
Likely causes:
- Meter off or comms wiring.
On the SPH 3000-6000TL BL-UP (48 V battery hybrid)
The manual says: SP-CT/Meter Communication fault.
Part involved: Energy meter / CT clamp communication.
Likely causes:
- SP-CT/Meter Communication fault.
Is it safe?
| Does the inverter stop? | Partly |
|---|---|
| Severity | Warning |
| Engineer needed? | Yes |
The inverter keeps running with some functions stopped.
Resetting itself: yes - clears when communication is restored.
Manual reset: no.
What you can check
- Read and note the exact code and time from the inverter display or app (screenshot).
- Check the meter's display is lit (look only).
- Note any recent electrical work near the meter/consumer unit.
- Growatt's manual says 'restart inverter'. A homeowner can switch the inverter off and on at its AC isolator/breaker; leave DC switching to the installer unless the manual step says to switch DC off immediately (Error 202).
What the engineer will check
- Check meter RS485/Modbus wiring polarity and termination.
- Check CT orientation (arrow towards grid/house per manual) and seating.
- Check meter address/baud settings.
- Check export-limit setting (G99) - some inverters stop if export control is on and meter lost.
Who to ask for: PV/battery installer.
Certification: Installer or electrician for meter/CT/comms cabling; homeowner can handle Wi-Fi/router issues.
What you might notice
Sources
- Growatt MIN 2500-6000TL-X Installation & Operation (User) Manual, general EN 2022-06 ↗ · EN 202206 · page PDF p.23 · Reviewed 24 September 2026
- Growatt SPH 3000-6000TL BL-UP User Manual EN 202512 ↗ · EN 202512 · page PDF p.61 · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026