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+18
What it means
AC lower frequency — The grid frequency is below the protection setting.
Cause: The measured grid frequency is below the configured protection limit.
How to fix it
Check the frequency protection setting.
Source: 041_BManual_SUN-120_125_130_135_136K-G01P3-EU-BM8_20251021_en_a2166559.pdf, p.63 · 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 · +4 more official manuals
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+71
What it means
AC lower frequency — The grid frequency is below the protection setting.
Cause: Grid frequency measured below the configured under-frequency protection limit.
How to fix it
Check the frequency protection setting.
Source: 063_BManual_SUN-6K-G06-LV-P1_20250923_en_30a96699.pdf, p.58 · 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.58
Also applies to:SUN-3.6K-SG05LP1-EU-SM2-PSUN-5K-SG05LP1-EU-SM2-PSUN-6K-SG05LP1-EU-SM2-PSUN-7K-SG05LP1-EU-SM2-PSUN-7.6K-SG05LP1-EU-SM2-PSUN-8K-SG05LP1-EU-SM2-PSUN-10K-SG05LP1-EU-SM2-PSUN-7.6K-SG01LP1-EU+21
What it means
AC lower frequency — Grid frequency out of range: the AC frequency is too low.
Cause: The grid frequency is below the range in the specification, or the AC cables are not firmly and correctly connected.
How to fix it
- 1Check that the frequency is in the range of the specification and that the AC cables are firmly and correctly connected.
- 2Seek help from Deye if the inverter cannot go back to the normal state.
Source: 039_BManual_SUN-3.6_5_6_7_7.6_8_10K-SG05LP1-EU-SM2-P_20260428_en_70c401a6.pdf, p.50 · 043_BManual_SUN-12_14_16K-SG01LP1-EU_20260519_en_703e15ac.pdf, p.46 · 052_BManual_SUN-_3.6-6_K-OG01LP1-EU-AM2_20260406_en_dc31b173.pdf, p.46 · +4 more official manuals
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
Grid Underfrequency — AC_UnderFreq_Fault - grid frequency out of range (too low).
Cause: The grid frequency is below the range given in the specification.
How to fix it
- 1Check whether the frequency is in the range of the specification
- 2Check whether the AC cables are firmly and correctly connected.
Source: 037_BManual_SUN-5_6_8_10_12_15_20_25K-SG01HP3-EU-AM2_20260224_en_9ef2717c.pdf, p.51 · 050_BManual_SUN-29.9_30_35_40_50K-SG01HP3-EU-BM3_4_20260224_en_544e1b2f.pdf, p.52 · 062_BManual__SUN-60_70_75_80K-SG02HP3-EU-EM6_20260224_en_38cbc9f6.pdf, p.52
Also applies to:SUN-5K-SG02LP2-US-AM2SUN-6K-SG02LP2-US-AM2SUN-7.6K-SG02LP2-US-AM2SUN-8K-SG02LP2-US-AM2SUN-10K-SG02LP2-US-AM3SUN-12K-SG02LP2-US-AM3SUN-5K-SG04LP3-EUSUN-6K-SG04LP3-EU+15
What it means
AC Underfrequency — AC lower frequency - grid frequency out of range (too low).
Cause: The grid frequency is below the range given in the specification.
How to fix it
- 1Check whether the frequency is in the range of the specification
- 2Check whether the AC cables are firmly and correctly connected
- 3Seek help from us if it cannot go back to the normal state.
Source: 059_BManual_SUN-5_6_7.6_8_10_12K-SG02LP2-US-AM2_AM3_20260406_en_fb6a30c7.pdf, p.55 · 038_BManual_SUN-5_6_8_10_12K-SG04LP3-EU_20260319_en_081932c1.pdf, p.47 · 040_BManual_SUN-3_4_5_6_8_10_12K-SG05LP3-EU-SM2_20260319_en_b0183b7d.pdf, p.47 · +1 more official manuals
Energy storage systemFault Also applies to:AI-W5.1-5P3-EU-B-ESSAI-W5.1-6P3-EU-B-ESSAI-W5.1-8P3-EU-B-ESSAI-W5.1-10P3-EU-B-ESSAI-W5.1-12P3-EU-B-ESS
What it means
AC lower frequency — Grid frequency out of range (too low).
Cause: The grid frequency is below the range configured in the specification, or the AC cables are loose/incorrectly connected.
How to fix it
- 1Check that the grid frequency is within the specified range and that the AC cables are firmly and correctly connected.
- 2Seek help from Deye if it does not recover.
Source: 002_Download_4e90fe7a.pdf, p.48
Energy storage systemFault Also applies to:GB-SL5K-EUGB-SL6K-EUGB-SL8K-EUGB-SL10K-EUGB-SL12K-EUGB-SL15K-EUGB-SL20K-EUGB-SL Pro 5K-EU+6
What it means
AC_UnderFreq_Fault — Grid frequency out of range (too low).
Cause: The grid frequency is below the range configured in the specification, or the AC cables are loose/incorrectly connected.
How to fix it
- 1Check that the grid frequency is within the specified range and that the AC cables are firmly and correctly connected.
- 2Seek help from Deye if it does not recover.
Source: 081_deye_gb_sl_pro_user_manual_46fa941a.pdf, p.50 · 010_Download_cc05df18.pdf, p.45
Also applies to:RW-L2.5ARW-L5.1RW-L10.2RW-F16SE-F5SE-F5 PlusSE-F5 ProSE-F12+7
What it means
Heat error — The heating function failed.
Cause: The heating film did not warm the cells as commanded or the heating circuit reported an abnormal state - a fault in the heater or its control circuit.
How to fix it
- 1Restart the battery.
- 2If heating still fails in cold conditions, 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
Also applies to:GB-A
What it means
ALARM_ID_BMU_COMM_ERROR — The BMU communication is faulty.
Cause: The internal bus between the BMS and one or more battery modules (BMUs) dropped - module wiring or a module board fault.
How to fix it
- 1Check the inter-module communication cabling and restart the system.
- 2If the fault persists, contact Deye support.
Source: 008_deye_ess_user_manual_gb_a_jpnen_v02_20250829_3fea617e.pdf, p.14