DTC Detection Debugging Guide¶

What to Look For in Home Assistant Logs¶

After reducing log verbosity, the DTC detection process is now clearly visible with these markers:

✅ Success Path¶

INFO - Starting automatic inverter type detection
INFO - ✓ DTC Detection - Read DTC code: 5400 from holding register 30000
INFO - ✓ DTC Detection - Matched DTC code 5400 to profile 'mod_6000_15000tl3_xh'
INFO - ✓ Auto-detected from DTC code 5400: MOD 6000-15000TL3-XH

⚠️ Failure Indicators¶

DTC Read Failed:

INFO - Starting automatic inverter type detection
WARNING - Failed to read DTC code from register 30000: [error details]
INFO - DTC and model name detection failed, trying register-based detection...

DTC Returns Zero:

INFO - Starting automatic inverter type detection
WARNING - DTC code register 30000 returned 0 or invalid value: 0
INFO - DTC and model name detection failed, trying register-based detection...

Unknown DTC Code:

INFO - ✓ DTC Detection - Read DTC code: 9999 from holding register 30000
WARNING - ✗ DTC Detection - Unknown DTC code: 9999 (not in supported models)
INFO - DTC and model name detection failed, trying register-based detection...

Valid DTC Codes¶

DTC codes are read from holding register 30000 (VPP models) or register 43 (legacy models). Each code maps to a specific profile.

Model names below follow Growatt VPP 2.03 protocol documentation, Table 3-1.

Reading the Status column¶

The DTC is read from your inverter, so it identifies the model reliably. Whether the profile we point that model at is correct for it is a separate question:

Status	Meaning
✅ Confirmed	A real device reporting this DTC has been seen running this profile, and the confirmation is traceable to an issue or register scan.
⚠️ Unconfirmed	The mapping comes from Growatt's model table only. It has never been checked against hardware. Sensors may be missing, or present but meaningless.

An unconfirmed mapping is not necessarily wrong — most are probably fine. It means nobody has verified it. If your model shows ⚠️, a register scan attached to a GitHub issue is what turns it into ✅.

These statuses live in DTC_REGISTRY in auto_detection.py, which is the single source of truth; this page is checked against it by the test suite.

Legacy Protocol (register 43, no VPP support)¶

DTC Code	Model Series	Profile	Status
210	MIC 2500-5500MTL-S	mic_2500_5500mtl_s	✅ Confirmed (#304)
2049	TL3-S 3000-15000	tl3_s_3000_15000	✅ Confirmed (#299)

SPF Series — Off-Grid (register 43)¶

⚠️ Off-grid inverters will reset if VPP registers (30000+, 31000+) are accessed. The integration skips those ranges automatically when an SPF DTC is detected.

DTC Code	Model Series	Profile	Status
3400	SPF 3000-6000 ES PLUS	spf_3000_6000_es_plus	⚠️ Unconfirmed
3401	SPF 3000-6000 ES PLUS (variant)	spf_3000_6000_es_plus	⚠️ Unconfirmed
3402	SPF 3000-6000 ES PLUS (variant)	spf_3000_6000_es_plus	⚠️ Unconfirmed
3403	SPF 3000-6000 ES PLUS (variant)	spf_3000_6000_es_plus	⚠️ Unconfirmed

SPH / SPA Series — Single-Phase Hybrid¶

SPA owners, please read. SPA models are AC-coupled battery storage with no solar DC inputs. Every SPA code below currently maps to an SPH profile, which includes PV sensors — so you will see PV entities that read zero permanently. They are not faulty; your inverter has no MPPT inputs for them to measure. A dedicated SPA profile is in progress (#360).

DTC Code	Model Series	Profile	Status
3501	SPH 3000-6000TL BL	sph_3000_6000_v201	⚠️ Unconfirmed
3502	SPH 3000-6000TL BL-UP	sph_3000_6000_v201	✅ Confirmed (#337)
3503	SPH 3000-6000TL HU	sph_3000_6000_v201	⚠️ Unconfirmed
3504	SPH 3000-6000TL HUB	sph_3000_6000_v201	✅ Confirmed (#286)
3601	SPH 4-10KTL3 BH-UP	sph_tl3_3000_10000_v201	✅ Confirmed (#210)
3701	SPA 1000-3000TL BL	sph_3000_6000_v201	⚠️ Unconfirmed — SPH profile on SPA hardware
3715	SPA 3000-6000TL AU	sph_3000_6000_v201	⚠️ Unconfirmed — SPH profile on SPA hardware
3716	SPA 3000-6000TL AUB	sph_3000_6000_v201	⚠️ Unconfirmed — SPH profile on SPA hardware
3725	SPA 4-10KTL3 BH-UP	spa_tl3_4000_10000_v201	✅ Confirmed — register layout verified on hardware
3735	SPA 3000TL BL-UP	sph_3000_6000_v201	⚠️ Unconfirmed — SPH profile on SPA hardware
21303	SPH/SPM 8000-10000TL-HU	sph_8000_10000_hu	✅ Confirmed (scan #303)

SPE Series — Single-Phase Hybrid (SPF protocol, 8-12 kW)¶

DTC Code	Model Series	Profile	Status
64541	SPE 8000-12000 ES	spe_8000_12000_es	✅ Confirmed (scan #212)

MIN / MIC Series — Single-Phase Grid-Tied / Hybrid¶

DTC Code	Model Series	Profile	Status
5100	MIN 2500-6000TL-XH/XH2/XHE/XA	tl_xh_3000_10000_v201	✅ Confirmed (#71)
5200	MIC 600-3300TL-X/X2/X2(Pro); MIN 2500-6000TL-X/X2/X2(Pro)/X2(Pro.E)	min_3000_6000_tl_x_v201	⚠️ Unconfirmed — refined at runtime by per-MPPT energy check
5201	MIN 7-10KTL-X/X2/X2(E)	min_7000_10000_tl_x_v201	✅ Confirmed (MIN 10000TL-X, DTC from legacy holding 43)

MOD / MID / MAC Series — Three-Phase Hybrid / Grid-Tied¶

DTC Code	Model Series	Profile	Status
5400	MOD 3-10KTL3-XH/BP; MID 11-30KTL3-XH; MID 8-15KTL3-XHL/JP	mod_6000_15000tl3_xh_v201	✅ Confirmed (#313, #362)
5401	MOD 3-15KTL3-HU; MID 33-50KTL3-HU	mod_6000_15000tl3_xh_v201	✅ Confirmed (scan #228)
5001	MID 17-25KTL3-X; MID 20-30KTL3-X2; MID 25-30KTL3-X2 Pro/X2 Pro.E; MID 33-50KTL3-X2/X2 Pro/X2 Pro.E; MID 30-40KTL3-X; MID 33-36KTL3-X(Pro.E); MID 3-33KTL3-X3	mid_15000_25000tl3_x_v201	✅ Confirmed (#242)
5002	MOD 3-15KTL3-X; MOD 3-15KTL3-X2(Pro); MOD 12-20KTL3-X2; MOD 12-20KTL3-X2(E); MOD 3-33KTL3-X3	mid_15000_25000tl3_x_v201	⚠️ Unconfirmed
5003	MAC 30-70KTL3-X; MAC 15-36KTL3-XL; MAC 50-70KTL3-X2; MAC 30-36KTL3-XL2	mid_15000_25000tl3_x_v201	⚠️ Unconfirmed — no dedicated MAC profile

MAX / MAX-X Series — Large Commercial Grid-Tied¶

No MAX device has been seen by this integration. These map to the MID profile as the closest available — per Table 3-1, MAX/MAX-X do not use battery or energy-storage registers, so they belong with the grid-tied group above. All four are unverified guesses. If you own one, a register scan would be genuinely valuable.

DTC Code	Model Series	Profile	Status
5000	MAX 50-100KTL3 LV/MV	mid_15000_25000tl3_x_v201	⚠️ Unconfirmed — no MAX profile exists
5500	MAX 175-253KTL3-X HV	mid_15000_25000tl3_x_v201	⚠️ Unconfirmed — no MAX profile exists
5501	MAX 80-150KTL3-X LV/MV; MAX 100-150KYL3-X2 LV/MV	mid_15000_25000tl3_x_v201	⚠️ Unconfirmed — no MAX profile exists
5502	MAX 320-350KTL3-X	mid_15000_25000tl3_x_v201	⚠️ Unconfirmed — no MAX profile exists

WIT / WIS Series — Three-Phase Commercial Hybrid¶

DTC Code	Model Series	Profile	Status
5601	WIT 29.9-50K-XHU	wit_29900_50000tl3_xhu	✅ Confirmed (scan #338)
5600	WIS 100K-AM; WIT 50-100K-H/HE/HU/A/AE/AU (incl. -US); WIT 28-55K-H/HE/HU/A/AE/AU-US L2	wit_29900_50000tl3_xhu	⚠️ Unconfirmed — interim; VPP 31200+ not available on 100K-HU (#349)
5603	WIT 4-15kW	wit_4000_15000tl3	✅ Confirmed (#335)
5800	WIS 210K	mid_15000_25000tl3_x_v201	⚠️ Unconfirmed — uses MID profile
5801	WIS 215K-AM	mid_15000_25000tl3_x_v201	⚠️ Unconfirmed — uses MID profile

How to View Logs in Home Assistant¶

Method 1: Via UI¶

Go to Settings → System → Logs
Search for "DTC Detection"
Look for ✓ or ✗ markers

Method 2: Via Log File¶

# View live logs
tail -f /config/home-assistant.log | grep "DTC"

# Search recent logs
grep "DTC Detection" /config/home-assistant.log | tail -20

# Full detection sequence
grep -A 5 "Starting automatic inverter type detection" /config/home-assistant.log | tail -30

Common Issues and Solutions¶

Issue 1: DTC Read Fails Immediately¶

Symptom:

WARNING - Failed to read DTC code from register 30000: [ModbusIOException]

Possible Causes: - Emulator not running or not accessible - Wrong host/port in HA configuration - Firewall blocking connection - Modbus device ID mismatch

Debug Steps:

# Test from HA machine
python3 test_modbus_dtc.py --host <emulator-ip> --port 502

# Check network connectivity
ping <emulator-ip>
telnet <emulator-ip> 502

Issue 2: DTC Returns Zero¶

Symptom:

WARNING - DTC code register 30000 returned 0 or invalid value: 0

Possible Causes: - Emulator profile doesn't define DTC default value - Register 30000 not implemented in holding registers - Reading from wrong register type (input vs holding)

Debug Steps: 1. Check emulator is serving register 30000:

python3 test_dtc_code.py

2. Verify it's a HOLDING register (not input) 3. Check MOD profile has default: 5400 for register 30000

Issue 3: Connection Works in Modbus Poll but Not HA¶

Symptom: - Modbus Poll can read DTC code 5400 - HA logs show "Failed to read DTC code"

Possible Causes: - Device ID mismatch (HA using different ID than Modbus Poll) - Timeout too short in HA - Register address offset issue

Debug Steps: 1. Check device ID in both tools: - Modbus Poll: usually shown in connection settings - HA: check config entry or use device_id=1 2. Increase timeout in HA config 3. Verify register address is exactly 30000 (not 30001 or 29999)

Issue 4: Unknown DTC Code¶

Symptom:

WARNING - ✗ DTC Detection - Unknown DTC code: 5400 (not in supported models)

Possible Causes: - Integration doesn't have 5400 mapped to a profile - Old version of integration

Solution: Check auto_detection.py has this mapping:

dtc_map = {
    ...
    5400: 'mod_6000_15000tl3_xh',  # MOD-XH\MID-XH
    ...
}

Testing DTC Detection¶

Test 1: Verify Emulator Serves DTC¶

python3 test_dtc_code.py

Expected output:

✓ Model loaded: MOD 6000-15000TL3-XH
✓ Simulated value: 5400
✓ CORRECT! DTC code 5400 for MOD series

Test 2: Test Modbus Connection¶

python3 test_modbus_dtc.py --host localhost --port 502

Expected output:

✓ Connected successfully
✓ Valid DTC code: MOD-XH/MID-XH
Value: 5400

Test 3: Watch HA Logs Live¶

# In one terminal - watch logs
tail -f /config/home-assistant.log | grep -E "DTC|auto.*detect"

# In another terminal - reload integration
# (via HA UI: Settings → Integrations → Growatt → Reload)

What Changed¶

Before (Verbose):¶

INFO - Fixed config entry to store register map key: MOD_6000_15000TL3_XH
INFO - Identified register map as: MOD_6000_15000TL3_XH
INFO - Initialized Growatt client with register map: MOD_6000_15000TL3_XH
INFO - Midnight callback registered for daily total resets
INFO - Read serial number: GRW12345678
INFO - Read firmware version: 1.39
INFO - Read inverter type: MOD-15000TL3-XH
INFO - Read protocol version: VPP 2.01
INFO - Detected 3-phase hybrid - SPH TL3 or MOD series
INFO - Detected 31200 range (VPP Protocol) - MOD series

After (Clean):¶

INFO - Starting automatic inverter type detection
INFO - ✓ DTC Detection - Read DTC code: 5400 from holding register 30000
INFO - ✓ DTC Detection - Matched DTC code 5400 to profile 'mod_6000_15000tl3_xh'
INFO - ✓ Auto-detected from DTC code 5400: MOD 6000-15000TL3-XH
INFO - Midnight reset triggered - storing previous day totals

Routine operations are now at DEBUG level - enable debug logging if needed:

logger:
  default: info
  logs:
    custom_components.growatt_modbus: debug