W31Warning

DEYE inverter error W31

Battery Communication Warning

Warningthe red LED flashes and the inverter keeps running. Deal with it before it escalates.

Also applies to:SUN-5K-SG01HP3-EU-AM2SUN-6K-SG01HP3-EU-AM2SUN-8K-SG01HP3-EU-AM2SUN-10K-SG01HP3-EU-AM2SUN-12K-SG01HP3-EU-AM2SUN-15K-SG01HP3-EU-AM2SUN-20K-SG01HP3-EU-AM2SUN-25K-SG01HP3-EU-AM2+9

What it means

Battery Communication WarningBattery_comm_warn - abnormal communication between the inverter and the battery.

Cause: The BMS connection is unstable, or the BMS data is abnormal.

How to fix it

  1. Check whether the BMS connection is stable
  2. Check whether the BMS data is abnormal.

Source: 037_BManual_SUN-5_6_8_10_12_15_20_25K-SG01HP3-EU-AM2_20260224_en_9ef2717c.pdf, p.48 · 050_BManual_SUN-29.9_30_35_40_50K-SG01HP3-EU-BM3_4_20260224_en_544e1b2f.pdf, p.49 · 062_BManual__SUN-60_70_75_80K-SG02HP3-EU-EM6_20260224_en_38cbc9f6.pdf, p.49

Frequently asked questions

What does error W31 mean on a DEYE inverter?
W31 means: Battery Communication Warning. The BMS connection is unstable, or the BMS data is abnormal.
Is error W31 a fault or a warning?
W31 is a warning: the red LED flashes and the unit keeps running. Fix the underlying condition before it escalates.
How do I clear or fix error W31?
1. Check whether the BMS connection is stable.

Related error codes

Prefer the full written guide? Read the complete DEYE inverter error-code guide

Compiled from official DEYE user manuals. Always consult your device manual and a qualified technician before performing repairs.