27Fault

DEYE inverter error 27 (F027)

DC end insulation error

Also displayed as F027 / F27 on some models.

Fault — the inverter cuts its output and the red LED stays solid until the fault is cleared.

The exact meaning depends on your model:

SUN G01P3-EU-BM8 Series

InverterFault

Also applies to:SUN-120K-G01P3-EU-BM8SUN-125K-G01P3-EU-BM8SUN-130K-G01P3-EU-BM8SUN-135K-G01P3-EU-BM8SUN-136K-G01P3-EU-BM8SUN-7K-G02P1-EU-AM2SUN-7.5K-G02P1-EU-AM2SUN-8K-G02P1-EU-AM2+3

What it means

DC end insulation error — An insulation error was detected at the DC end. The manual notes this code has hardly ever appeared in the field.

Cause: The insulation at the DC end of the power stage fell below the acceptable level.

How to fix it

Restart the inverter; if the code persists after the restart, contact your installer or Deye service and provide the inverter serial number, the installation date and the displayed error code.

Source: 041_BManual_SUN-120_125_130_135_136K-G01P3-EU-BM8_20251021_en_a2166559.pdf, p.62 · 065_BManual_SUN-7_7.5_8K-G02P1-EU-AM2_20260625_en_4466f08b.pdf, p.52 · 032_BManual_SUN-9_10_10.5K-G02P1-EU-AM2_20260625_en_df0f2106.pdf, p.52

SUN G03/G01P3-AM8 Series

InverterFault

Also applies to:SUN-60K-G03SUN-70K-G03SUN-75K-G03SUN-80K-G03SUN-90K-G03SUN-100K-G03SUN-110K-G03SUN-60K-G01P3-EU-AM8-LV+7

What it means

DC end insulation error — An insulation error was detected at the DC end.

Cause: The insulation at the DC end of the power stage fell below the acceptable level.

How to fix it

Restart the inverter; if the fault is not ruled out, contact the installer or the manufacturer's customer service.

Source: 033_BManual_SUN-70_75_80_90_100_110K-G03_20260702_en_a9db1e1b.pdf, p.62 · 042_BManual_SUN-120_125_130_135_136K-G01P3-EU-AM8_20260702_en_05f936e3.pdf, p.61 · 060_BManual_SUN-60_70_75K-G01P3-EU-AM8-LV_20260701_en_f559aeec.pdf, p.61 · +1 more official manuals

SUN G04/G05/G06 3-Phase

InverterFault

Also applies to:SUN-6K-G06-LV-P1SUN-8K-G06-LV-P1SUN-6K-G06P3-EU-BM2-LV-P1SUN-8K-G06P3-EU-BM2-LV-P1SUN-10K-G05-LVSUN-12K-G05-LVSUN-15K-G05-LVSUN-15K-G06P3-EU-BM2-P1+27

What it means

DC end insulation error — Insulation error detected at the DC end.

Cause: The insulation impedance at the DC terminal end fell below the limit.

How to fix it

Restart the inverter; if the fault is not ruled out, contact the installer or manufacturer customer service.

Source: 063_BManual_SUN-6K-G06-LV-P1_20250923_en_30a96699.pdf, p.57

SUN G04P1/G05P1 Series

InverterFault

Also applies to:SUN-1K-G04P1-EU-AM1SUN-1.5K-G04P1-EU-AM1SUN-2K-G04P1-EU-AM1SUN-2.2K-G04P1-EU-AM1SUN-2.5K-G04P1-EU-AM1SUN-2.7K-G04P1-EU-AM1SUN-3K-G04P1-EU-AM1SUN-3.3K-G04P1-EU-AM1+36

What it means

DC end insulation error — Insulation error detected at the DC end.

Cause: The insulation impedance at the DC terminal end fell below the limit.

How to fix it

Deye states this code has hardly ever appeared in the field; contact your installer or Deye service if it occurs.

Source: 031_BManual_SUN-1_1.5_2_2.2_2.5_2.7_3_3.3_3.6_4K-G04P1-EU-AM1_20260624_en_15adc00c.pdf, p.54 · 036_BManual_SUN-3_4_5_6_7_8_9_10_12_15K-G06P3-EU-BM2_20250506_en_0eb78440.pdf, p.57

SUN SG01HP3/SG02HP3 Hybrid

InverterFault

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

DC Insulation Fault (Internal) — DC_Insulation_Fault - internal DC insulation fault.

Cause: The inverter's DC insulation monitoring reported a fault.

How to fix it

Restart the inverter 3 times and restore the factory settings.

Source: 037_BManual_SUN-5_6_8_10_12_15_20_25K-SG01HP3-EU-AM2_20260224_en_9ef2717c.pdf, p.50 · 050_BManual_SUN-29.9_30_35_40_50K-SG01HP3-EU-BM3_4_20260224_en_544e1b2f.pdf, p.51 · 062_BManual__SUN-60_70_75_80K-SG02HP3-EU-EM6_20260224_en_38cbc9f6.pdf, p.51

RW Spring Series Battery

BatteryFault

Also applies to:RW-L2.5ARW-L5.1RW-L10.2RW-F16SE-F5SE-F5 PlusSE-F5 ProSE-F12+7

What it means

Temperature sampling fails — A temperature sensor returned an invalid reading.

Cause: An NTC temperature sensor is open-circuit, shorted, or disconnected inside the pack, so the BMS cannot read a valid temperature.

How to fix it

  1. Restart the battery.
  2. If the code persists, the sensor circuit needs service - contact Deye support.

Source: 093_Deye_RW-L2.5A_User_Manual_EN_89188fb8.pdf, p.10 · 019_Download_4a609b7e.pdf, p.10 · 021_Download_f81ba1e7.pdf, p.10 · +6 more official manuals

GB-A HV Battery

BatteryFault

Also applies to:GB-A

What it means

ALARM_ID_BMU_ADDR_REPEAT — Duplicate BMU address (the manual's description column reads 'the BMU repeatedly fails'; the alarm ID identifies a repeated BMU address).

Cause: Two battery modules (BMUs) are configured with the same address on the internal bus.

How to fix it

  1. Correct the module addressing so every BMU has a unique address, then power-cycle the system.
  2. Contact Deye support if addresses cannot be changed on site.

Source: 008_deye_ess_user_manual_gb_a_jpnen_v02_20250829_3fea617e.pdf, p.13

Frequently asked questions

What does error 27 mean on a DEYE inverter?
It depends on the model — 10 devices use code 27. On the SUN G01P3-EU-BM8 Series it means: DC end insulation error. The card for each model on this page gives its exact meaning and fix.
Is error 27 a fault or a warning?
27 is a fault code: the inverter cuts its output and the red LED stays solid until it is cleared.
How do I clear or fix error 27?
Restart the inverter; if the code persists after the restart, contact your installer or Deye service and provide the inverter serial number, the installation date and the displayed error code. The exact steps for each affected model are listed on this page.

Related error codes

Other codes on the SUN G01P3-EU-BM8 Series

All SUN G01P3-EU-BM8 Series codes All SUN G02P1-EU Series codes

Other codes on the SUN G03/G01P3-AM8 Series

All SUN G03/G01P3-AM8 Series codes

Other codes on the SUN G04/G05/G06 3-Phase

All SUN G04/G05/G06 3-Phase codes

Other codes on the SUN G04P1/G05P1 Series

All SUN G04P1/G05P1 Series codes All SUN G06P3-EU Series codes

Other codes on the SUN SG01HP3/SG02HP3 Hybrid

All SUN SG01HP3/SG02HP3 Hybrid codes

Other codes on the RW Spring Series Battery

All RW Spring Series Battery codes All SE Spring Series Battery 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.