Pre-Commissioning Process for CHINT Meters

Document Information 
 
 Version : 1.0 
 Last Updated : 2026-04-04 
 Target Audience : Field Operations Team, Development Team, Remote Commissioning Team 
 
 
 Table of Contents 
 
 Introduction 
 Team Roles and Responsibilities 
 Equipment and Software Requirements 
 Pre-Commissioning Workflow 
 Converter Tool Guide 
 Troubleshooting Guide 
 Safety and Best Practices 
 Inventory Management 
 Future Enhancements 
 
 
 Introduction 
 Purpose of Pre-Commissioning 
 Pre-commissioning is the process of converting CHINT DDSU666/DTSU666 meters from their native DL/T645 protocol to Modbus RTU protocol and assigning unique Modbus addresses before the meters are installed at customer sites. 
 Why Pre-Commissioning Matters 
 Problem : Fresh CHINT meters operate on the Chinese DL/T645 protocol and default to Modbus address 1 after conversion. If meters are converted on-site: 
 
 Address collisions occur when multiple meters default to address 1 
 Production disruption happens when using the production USB-RS485 adapter for conversion (interrupts live meters) 
 Field complexity increases with protocol conversion and addressing at customer locations 
 
 Solution : Pre-commission all meters in a controlled lab environment before field deployment. 
 Benefits 
 ✅ Zero Downtime : Field installation becomes plug-and-play (physical connection only)
✅ No Address Conflicts : Each meter arrives with unique, pre-assigned Modbus address
✅ Quality Control : Test meter communication before shipping
✅ Simplified Installation : Field team doesn't need protocol conversion tools
✅ Audit Trail : Complete inventory tracking from procurement to commissioning 
 
 Team Roles and Responsibilities 
 Development Team 
 Responsibilities : 
 
 Assign Modbus addresses based on site requirements and numbering scheme 
 Maintain master meter inventory spreadsheet 
 Build and distribute converter.exe updates 
 Provide escalation support for complex technical issues 
 Plan and design system upgrades 
 
 Tools Used : 
 
 Master Inventory Spreadsheet (Nextcloud Sheets) 
 PyInstaller (for building Windows executable) 
 
 
 Field Operations Team 
 Responsibilities : 
 
 Execute lab conversion of meters from DL/T645 → Modbus RTU 
 Assign Modbus addresses per Development Team's mapping 
 Test meter responses after conversion 
 Update inventory status (Assigned → Converted → Shipped) 
 Label meters physically with assigned Modbus address 
 Package and ship pre-configured meters to sites 
 
 Tools Used : 
 
 converter.exe (Windows GUI application) 
 USB-RS485 adapter (dedicated lab adapter, NOT production) 
 Meter Inventory Spreadsheet (Nextcloud Sheets) 
 Physical label maker/stickers 
 
 Training Required : 
 
 Converter tool operation (see Converter Tool Guide ) 
 Inventory management workflow 
 Basic RS485 wiring (A+/B- terminals) 
 
 
 Field Installation Team 
 Responsibilities : 
 
 Mount meter at customer location 
 Wire power connections (L1/L2/L3/N) 
 Wire current transformers (if three-phase meter) 
 Connect to existing Modbus RS485 bus (A+/B- terminals) 
 Verify meter powers up and displays readings 
 Notify Remote Commissioning Team when installation complete 
 
 Tools Used : 
 
 Standard electrical installation tools 
 Multimeter for continuity checks 
 
 Training Required : 
 
 Meter mounting procedures 
 RS485 bus connection (parallel wiring to existing meters) 
 Safety protocols for live electrical work 
 
 
 Remote Commissioning Team 
 Responsibilities : 
 
 Connect to Raspberry Pi remotely via ZeroTier + SSH 
 Add meter entry to production config file (config.prod.yaml) 
 Deploy configuration changes using automated script 
 Monitor service restart and verify meter logging 
 Update inventory status (Installed → Commissioned) 
 Notify stakeholders when meter is live 
 
 Tools Used : 
 
 ZeroTier VPN client 
 SSH client (Terminal, PuTTY, etc.) 
 Text editor (nano, vim) 
 add_meter.sh CLI helper script (recommended) 
 
 Training Required : 
 
 SSH basics and remote access 
 YAML syntax for meter configuration 
 Deployment script usage 
 Log monitoring with systemctl/journalctl 
 
 
 Equipment and Software Requirements 
 Hardware (Field Operations Team) 
 
 
 
 Item 
 Specification 
 Purpose 
 Notes 
 
 
 
 
 USB-RS485 Adapter 
 CH340, FTDI, or PL2303 chipset 
 Connect Windows PC to meter 
 CRITICAL : Use dedicated lab adapter, NOT production adapter 
 
 
 Windows PC/Laptop 
 Windows 7/10/11 
 Run converter.exe GUI 
 Must have USB port 
 
 
 Power Supply 
 230V AC (single-phase) or 3-phase 
 Power meter during conversion 
 Match meter type 
 
 
 RS485 Wiring 
 2-wire twisted pair 
 Connect adapter to meter A+/B- terminals 
 Keep wiring short (<2 meters) 
 
 
 Label Maker 
 Any type 
 Create Modbus address labels 
 Physical labels prevent confusion 
 
 
 
 Software (Field Operations Team) 
 
 
 
 Item 
 Location 
 Version 
 Purpose 
 
 
 
 
 converter.exe 
 Nextcloud: /Field_Operations/Tools/converter_v1.0.exe 
 v1.0 
 Protocol conversion and address assignment 
 
 
 USB Driver 
 Manufacturer website 
 Latest 
 CH340/FTDI/PL2303 driver for Windows 
 
 
 Meter Inventory 
 Nextcloud Sheets (shared link) + Excel backup on Nextcloud 
 Current 
 Track meter status 
 
 
 
 Download Links : 
 
 CH340 Driver: http://www.wch.cn/downloads/CH341SER_EXE.html 
 FTDI Driver: https://ftdichip.com/drivers/vcp-drivers/ 
 PL2303 Driver: http://www.prolific.com.tw/US/ShowProduct.aspx?p_id=225 
 
 
 Pre-Commissioning Workflow 
 Overview: 5-Phase Process 
 Phase 1: Address Assignment (Development Team)
 ↓
Phase 2: Lab Conversion (Field Operations Team)
 ↓
Phase 3: Pre-Dispatch Testing (Field Operations Team)
 ↓
Phase 4: Field Installation (Field Installation Team)
 ↓
Phase 5: Remote Commissioning (Remote Commissioning Team)
 
 
 Phase 1: Address Assignment (Development Team) 
 Duration : 15-30 minutes per batch 
 Steps : 
 
 
 Receive Procurement List 
 
 New meters arrive from supplier 
 Record 12-digit serial numbers from meter labels 
 Note meter types (DDSU666 single-phase or DTSU666 three-phase) 
 
 
 
 Assign Modbus Addresses 
 
 Follow numbering scheme:
 
 Single-phase (DDSU666) : IDs 02 to 99 (90 meters max per site) 
 Three-phase (DTSU666) : IDs 100 and above (unlimited) 
 
 
 CRITICAL RULE : Never use address 1 (factory default, causes conflicts) 
 
 Example Assignment : 
 Site: Office Building A
- Meter Serial 200322016690 → Address 02 (Floor 1 Reception)
- Meter Serial 200322016691 → Address 03 (Floor 1 Office)
- Meter Serial 200322016692 → Address 04 (Floor 2 Office)
- Meter Serial 200415023456 → Address 100 (Main 3-Phase Supply)
 
 
 
 Update Master Inventory Spreadsheet 
 
 Open Nextcloud Sheets inventory (link in team resources) 
 Add new rows for each meter:
 
 Meter Serial Number (12 digits) 
 Meter Type (DDSU666 or DTSU666) 
 Site Name 
 Building/Customer Name 
 Assigned Modbus Address 
 Status: "Assigned" 
 Date Assigned: Today's date 
 Assigned By: Your name 
 
 
 
 
 
 Send Assignment List to Field Operations Team 
 
 Export assignment list as PDF or share Nextcloud Sheets link 
 Include any special instructions (e.g., priority meters, site notes) 
 
 
 
 
 Phase 2: Lab Conversion (Field Operations Team) 
 Duration : 5-10 minutes per meter
 Location : Lab/Office environment
 Tools : Windows PC, converter.exe, USB-RS485 adapter 
 Steps : 
 2.1 Physical Setup 
 
 
 Connect Meter to Power 
 
 Single-phase: Connect L (live) and N (neutral) 
 Three-phase: Connect L1, L2, L3, and N 
 Verify meter LCD powers on and displays readings 
 
 
 
 Connect USB-RS485 Adapter 
 
 Locate meter's RS485 terminals (usually labeled A+/B- or 485A/485B) 
 Connect adapter's A+ wire to meter's A+ terminal 
 Connect adapter's B- wire to meter's B- terminal 
 Polarity matters! Incorrect wiring causes "No response" errors 
 
 
 
 Connect Adapter to Windows PC 
 
 Plug USB end into PC USB port 
 Windows should detect and install driver automatically 
 If not, install driver manually (see Equipment section) 
 
 
 
 2.2 Launch Converter Tool 
 
 Run converter.exe 
 
 Double-click converter_v1.0.exe from Nextcloud download 
 GUI window opens with title "DLT645 to Modbus Converter" 
 Initial status shows red "● Disconnected" 
 
 
 
 2.3 Configure Connection 
 
 
 Detect Serial Port 
 
 Click "⟳ Refresh" button 
 Dropdown populates with available ports (e.g., COM3 , COM4 ) 
 If no ports appear:
 
 Check USB cable connection 
 Verify driver installed (Windows Device Manager → Ports) 
 Try different USB port 
 
 
 
 
 
 Select Port and Baud Rate 
 
 Select detected port from dropdown (e.g., COM3 ) 
 Baud rate: Keep default 2400 (DLT645 standard) 
 
 
 
 Connect to Port 
 
 Click "Connect" button 
 Status changes to green "● Connected" 
 All action buttons become enabled 
 Log shows: [HH:MM:SS] Connected → COM3 @ 2400 baud 
 
 
 
 2.4 Enter Meter Details 
 
 
 DLT645 Station Address (12 digits) 
 
 Find on meter label or LCD display 
 Example: 200322016690 
 Must be exactly 12 digits (tool validates) 
 
 
 
 Target Modbus Address (from assignment list) 
 
 Refer to Master Inventory for assigned address 
 Example: Address 02 for first single-phase meter 
 Valid range: 1-247 (but avoid address 1) 
 
 
 
 Reverse Address Bytes (checkbox) 
 
 Keep checked by default 
 Tool will auto-retry with this toggled if conversion fails 
 
 
 
 2.5 Execute Conversion (Recommended: Use "Full Process") 
 Option A: Full Process (Recommended for Field Operations) 
 
 Click "▶ Full Process" button 
 Tool automatically performs:
 
 Step 1/2 : Convert protocol (DLT645 → Modbus RTU) 
 Step 2/2 : Change Modbus address to target value 
 
 
 Watch log panel for progress:
 [14:23:15] ═══ Full Process Started ═══
[14:23:15] [1/2] Converting protocol — station=200322016690
[14:23:15] TX: FE FE FE FE 68 02 03 20 01 66 90...
[14:23:27] ✓ Protocol conversion done.
[14:23:27] [2/2] Changing Modbus address: 1 → 10
[14:23:30] ✓ Address set to 10.
[14:23:30] ═══ Full Process Complete ═══
 
 
 Success indicators :
 
 ✓ checkmarks for both steps 
 No ✗ errors in log 
 "Full Process Complete" message 
 
 
 
 Option B: Manual Step-by-Step (for troubleshooting) 
 If Full Process fails, try manual steps: 
 
 
 Convert Protocol First 
 
 Click "Convert Protocol" button 
 Tool sends DLT645 protocol-switch command 
 Wait 2-5 minutes for meter to respond 
 Log shows: ✓ Protocol conversion done. 
 
 
 
 Scan for Current Address (optional) 
 
 Click "🔍 Scan" button 
 Tool tests all 247 Modbus addresses (takes ~90 seconds) 
 Log shows: ✓ Meter found at Modbus address 1 
 "Current Modbus Address" field auto-updates 
 
 
 
 Change Address 
 
 Ensure "Current Modbus Address" is correct (usually 1 after conversion) 
 Enter "Target Modbus Address" (from assignment list) 
 Click "Change Modbus Addr" button 
 Log shows: ✓ Address changed to 10. 
 
 
 
 2.6 Update Inventory 
 
 Open Nextcloud Sheets Inventory 
 Find meter row (search by serial number) 
 Update fields :
 
 Status: Change "Assigned" → "Converted" 
 Date Converted: Today's date 
 Converted By: Your name 
 Notes: Add any issues encountered (e.g., "Required reverse byte toggle") 
 
 
 
 2.7 Label Meter Physically 
 
 Create Label (using label maker or sticker)
 
 Text: Modbus Address: 02 (use actual assigned address) 
 Include site name if space permits 
 
 
 Affix Label to Meter 
 
 Place on front panel or top cover 
 Ensure visible after installation 
 Prevents confusion during field installation 
 
 
 
 2.8 Disconnect and Repeat 
 
 
 Disconnect from Meter 
 
 Click "Disconnect" button in converter tool 
 Status returns to red "● Disconnected" 
 Unplug USB-RS485 adapter from PC 
 Disconnect adapter from meter terminals 
 Power off meter 
 
 
 
 Repeat for Next Meter 
 
 Proceed to next meter in batch 
 Follow steps 2.1-2.7 for each meter 
 
 
 
 
 Phase 3: Pre-Dispatch Testing (Field Operations Team) 
 Duration : 5 minutes per meter
 Purpose : Verify meter responds at assigned Modbus address before shipping 
 Steps : 
 
 
 Setup Test Bus 
 
 Connect 2-3 converted meters to same RS485 bus 
 Use twisted pair wiring (parallel connection) 
 Ensure meters have different addresses (e.g., 10, 11, 12) 
 
 
 
 Test Communication (Manual Method) 
 
 Connect USB-RS485 adapter to test bus 
 Open converter tool 
 Change baud rate to 9600 (Modbus standard) 
 Use "Scan" function to detect meters 
 Verify each meter responds at its assigned address 
 
 
 
 Alternative: Use NFE Test Script 
 
 If Raspberry Pi available for testing 
 Copy test_modbus_read.py script to test Pi 
 Edit script to test specific meter ID 
 Run: python3 test_modbus_read.py 
 Verify readings returned (voltage, current, power) 
 
 
 
 Record Test Results 
 
 Update inventory spreadsheet:
 
 Add checkmark or "Tested OK" in Notes column 
 If test fails, mark as "Retest Required" and escalate to Development Team 
 
 
 
 
 
 Package for Shipping 
 
 Power off meter 
 Ensure address label is visible 
 Package securely with protective materials 
 Include shipping label with site name 
 
 
 
 
 Phase 4: Field Installation (Field Installation Team) 
 Duration : 30-60 minutes per meter (excluding electrical prep)
 Location : Customer site
 Safety : Follow all electrical safety protocols 
 Steps : 
 4.1 Pre-Installation Checks 
 
 
 Verify Meter Received 
 
 Confirm meter serial number matches work order 
 Verify Modbus address label matches site plan 
 Inspect for shipping damage 
 
 
 
 Review Site Plan 
 
 Identify installation location 
 Locate existing Modbus RS485 bus terminals 
 Note power source (single-phase or three-phase) 
 
 
 
 4.2 Physical Installation 
 
 
 Mount Meter (per manufacturer instructions) 
 
 Use DIN rail mounting or wall mount bracket 
 Ensure meter is accessible for reading and maintenance 
 Keep away from excessive heat and moisture 
 
 
 
 Wire Power Connections 
 Single-Phase (DDSU666) : 
 
 Connect Line (L) from customer's circuit breaker 
 Connect Neutral (N) from customer's neutral bar 
 Verify polarity with multimeter 
 
 Three-Phase (DTSU666) : 
 
 Connect L1, L2, L3 from customer's supply 
 Connect Neutral (N) from neutral bar 
 If using current transformers (CTs):
 
 Install CTs on each phase conductor 
 Connect CT secondaries to meter CT terminals (K1/L1, K2/L2, K3/L3) 
 Ensure CT orientation matches current flow direction 
 
 
 
 
 
 Wire Modbus RS485 Bus 
 
 CRITICAL : This step must NOT interrupt existing meters 
 Locate existing RS485 bus terminals (A+/B- or 485A/485B) 
 Connect new meter's A+ terminal to bus A+ (parallel) 
 Connect new meter's B- terminal to bus B- (parallel) 
 Use twisted pair cable (CAT5 or dedicated RS485 cable) 
 Keep total bus length under 1200 meters 
 Use 120Ω termination resistor if meter is at end of bus 
 
 
 
 4.3 Power-Up and Verify 
 
 
 Energize Meter 
 
 Turn on customer circuit breaker 
 Meter LCD should illuminate and display readings 
 Verify voltage readings match expected values (230V ±10% single-phase, 400V ±10% three-phase) 
 
 
 
 Quick Communication Test (Optional) 
 
 If laptop with converter tool available:
 
 Connect USB-RS485 adapter to bus (parallel, don't disconnect existing) 
 Set baud rate to 9600 
 Use "Scan" to verify meter responds at assigned address 
 Disconnect adapter when done 
 
 
 If no laptop: Skip this step (Remote Commissioning Team will verify) 
 
 
 
 Notify Remote Commissioning Team 
 
 Send message: "Meter [Serial Number] installed at [Site Name], ready for commissioning" 
 Include photo of meter with label visible (for audit trail) 
 Update inventory:
 
 Status: "Converted" → "Installed" 
 Date Installed: Today's date 
 Installed By: Your name 
 
 
 
 
 
 
 Phase 5: Remote Commissioning (Remote Commissioning Team) 
 Duration : 10-15 minutes per meter
 Location : Remote (via ZeroTier VPN + SSH) 
 Prerequisites : 
 
 Receive notification from Field Installation Team 
 ZeroTier VPN client installed and connected to network ID: 2873fd00f2d70904 
 SSH access to production Raspberry Pi: nfetestpi2@10.135.127.86 
 
 Steps : 
 5.1 Connect to Raspberry Pi 
 
 
 Start ZeroTier VPN 
 
 Ensure ZeroTier client is running 
 Verify connected to "my-first-network" (ID: 2873fd00f2d70904) 
 Check ZeroTier shows "ONLINE" status 
 
 
 
 SSH to Production Pi 
 ssh nfetestpi2@10.135.127.86
 
 
 Enter password when prompted 
 Or use SSH key if configured (passwordless) 
 
 
 
 5.2 Add Meter to Configuration (Option A: Manual Edit) 
 For users comfortable with YAML editing : 
 
 
 Edit Staging Config 
 nano ~/nfe-modbus-energy-logger/config/config.prod.yaml
 
 
 
 Add Meter Entry 
 Scroll to the meters: section and add new entry: 
 Single-Phase Meter Example : 
 meters:
 # ... existing meters ...

 - id: 2 # Assigned Modbus address
 name: "floor1_reception" # Descriptive name (lowercase, underscores)
 type: "1phase" # Meter type
 enabled: true # Enable logging
 
 Three-Phase Meter Example : 
 meters:
 # ... existing meters ...

 - id: 100 # Assigned Modbus address
 name: "main_supply" # Descriptive name
 type: "3phase" # Meter type
 enabled: true # Enable logging
 
 Naming Conventions : 
 
 Use lowercase letters 
 Use underscores instead of spaces 
 Make names descriptive but concise 
 Examples: floor2_office , hvac_panel , server_room 
 
 
 
 Save and Exit 
 
 Press Ctrl+O to save 
 Press Enter to confirm filename 
 Press Ctrl+X to exit nano 
 
 
 
 5.2 Add Meter to Configuration (Option B: CLI Helper Script - RECOMMENDED) 
 For automated validation and safety : 
 
 
 Run Helper Script 
 ~/nfe-modbus-energy-logger-prod/scripts/add_meter.sh
 
 
 
 Answer Interactive Prompts 
 Enter Meter ID (2-247): 2
Enter Meter Name: floor1_reception
Enter Meter Type (1phase/3phase): 1phase
Enable meter? (yes/no): yes

About to add:
 ID: 2
 Name: floor1_reception
 Type: 1phase
 Enabled: true

Proceed? (yes/no): yes
 
 
 
 Script Automatically : 
 
 Validates input (address range, type, duplicate ID check) 
 Backs up current config 
 Appends meter to YAML 
 Runs deployment script 
 Monitors service restart 
 Verifies meter logging 
 Reports success or failure 
 
 
 
 Review Output 
 ✅ Meter 2 (floor1_reception) successfully added and logging
📁 Data directory: ~/nfe-modbus-energy-logger-prod/data/meter_010/
📊 CSV file: meter_010_2026-04-04.csv
 
 
 
 5.3 Deploy to Production (Manual Method Only) 
 Skip this if you used add_meter.sh script (already done) 
 
 
 Run Deployment Script 
 ~/nfe-modbus-energy-logger/scripts/deploy.sh
 
 
 
 Script Actions : 
 
 Backs up production directory 
 Syncs staging code to production 
 Runs pre-flight test (30-second dry run) 
 Restarts meter.service 
 Verifies service started successfully 
 Auto-rollback if service fails 
 
 
 
 Monitor Deployment 
 
 Watch for "Deployment complete" message 
 Check for any error messages 
 If errors occur, script auto-rolls back 
 
 
 
 5.4 Monitor Service Restart 
 
 
 Watch Service Logs 
 sudo journalctl -u meter.service -f
 
 
 
 Look for Meter Initialization 
 [timestamp] ✅ Initialized meter 10 (floor1_reception, 1phase)
[timestamp] 🚀 Starting multi-meter logger
[timestamp] Poll interval: 10s
[timestamp] Log interval: 900s (15 minutes)
[timestamp] Active meters: 3
 
 
 
 Press Ctrl+C to stop watching logs 
 
 
 5.5 Verify Meter Logging 
 
 
 Check Data Directory Created 
 ls -lh ~/nfe-modbus-energy-logger-prod/data/
 
 
 Should show new directory: meter_010/ (or corresponding ID) 
 
 
 
 Check CSV File Started 
 ls -lh ~/nfe-modbus-energy-logger-prod/data/meter_010/
 
 
 Should show CSV file: meter_010_2026-04-04.csv (today's date) 
 
 
 
 View Recent Log Entries 
 tail -20 ~/nfe-modbus-energy-logger-prod/data/meter_010/meter_010_2026-04-04.csv
 
 
 Should show recent readings with timestamps 
 Verify data fields populated (not all zeros or empty) 
 
 
 
 Sample Output : 
 timestamp,meter_id,V_L1_V,I_L1_A,P_total_kW,E_total_kWh,...
2026-04-04 15:15:00,10,234.5,2.1,0.49,12345.6,...
2026-04-04 15:30:00,10,235.1,2.3,0.53,12345.8,...
 
 
 
 5.6 Update Inventory and Notify 
 
 
 Update Inventory Spreadsheet 
 
 Status: "Installed" → "Commissioned" 
 Date Commissioned: Today's date 
 Commissioned By: Your name 
 Notes: Add any observations (e.g., "All readings nominal") 
 
 
 
 Verify Backup Enabled (if configured) 
 
 Check backup service runs successfully:
 sudo journalctl -u backup.service -n 50
 
 
 Verify meter CSV files being backed up to Nextcloud 
 
 
 
 Notify Stakeholders 
 
 Send confirmation message: "Meter [Serial Number] commissioned at [Site Name] - logging active" 
 Include link to meter data directory or dashboard (if available) 
 
 
 
 
 Converter Tool Guide 
 GUI Overview 
 ┌─────────────────────────────────────────────────────────┐
│ DLT645 to Modbus Converter │
├─────────────────────────────────────────────────────────┤
│ Serial Port: [COM3 ▼] [⟳ Refresh] [Connect] │
│ Baud Rate: [2400 ▼] │
│ Status: ● Connected │
├─────────────────────────────────────────────────────────┤
│ DLT645 Station Address (12 digits): │
│ [200322016690 ] │
│ │
│ Current Modbus Address: [1 ] [🔍 Scan] │
│ Target Modbus Address: [10 ] │
│ │
│ ☑ Reverse address bytes │
├─────────────────────────────────────────────────────────┤
│ [Convert Protocol] [Change Modbus Addr] [▶ Full Process]│
├─────────────────────────────────────────────────────────┤
│ Log Panel (scrollable): │
│ [14:23:15] Connected → COM3 @ 2400 baud │
│ [14:23:25] Converting protocol — station=200322016690 │
│ [14:23:27] ✓ Protocol conversion done. │
│ [14:23:30] ✓ Address changed to 10. │
│ │
└─────────────────────────────────────────────────────────┘
 
 Input Field Descriptions 
 
 
 
 Field 
 Description 
 Valid Values 
 Example 
 
 
 
 
 Serial Port 
 USB-RS485 adapter COM port 
 Auto-detected ports 
 COM3 
 
 
 Baud Rate 
 Communication speed 
 1200, 2400, 4800, 9600, 19200 
 2400 (DLT645 default) 
 
 
 DLT645 Station Address 
 Meter's 12-digit serial number 
 000000000000 - 999999999999 
 200322016690 
 
 
 Current Modbus Address 
 Address meter currently responds to 
 1-247 
 1 (factory default) 
 
 
 Target Modbus Address 
 New address to assign 
 1-247 
 10 (from assignment list) 
 
 
 Reverse Address Bytes 
 Toggle byte order for firmware compatibility 
 Checked/Unchecked 
 ☑ Checked (recommended) 
 
 
 
 Button Functions 
 
 
 
 Button 
 Function 
 When to Use 
 Duration 
 
 
 
 
 ⟳ Refresh 
 Re-scan for serial ports 
 USB adapter just connected 
 Instant 
 
 
 Connect 
 Open selected serial port 
 Before any conversion operations 
 Instant 
 
 
 Disconnect 
 Close serial port 
 After conversion complete 
 Instant 
 
 
 Convert Protocol 
 Send DLT645 protocol-switch command 
 Standalone protocol conversion 
 2-5 minutes 
 
 
 🔍 Scan 
 Search all 247 Modbus addresses 
 Find current meter address 
 ~90 seconds 
 
 
 Change Modbus Addr 
 Write new address to meter 
 After protocol conversion 
 5-10 seconds 
 
 
 ▶ Full Process 
 Automated conversion + address change 
 RECOMMENDED for Field Operations 
 5-10 minutes 
 
 
 
 Success Indicators 
 Look for these in the log panel : 
 ✅ Protocol Conversion Success : 
 [14:23:27] ✓ Protocol conversion done.
 
 ✅ Address Change Success : 
 [14:23:30] ✓ Address set to 10.
 
 ✅ Full Process Success : 
 [14:23:30] ═══ Full Process Complete ═══
 
 ✅ Meter Discovery Success : 
 [14:23:45] ✓ Meter found at Modbus address 1. 'Current Modbus Address' updated.
 
 Error Indicators 
 ❌ Communication Errors : 
 [14:23:27] ✗ No response — check wiring / address / baud rate.
 
 ❌ Validation Errors : 
 Validation Error: Station address must be exactly 12 digits.
Validation Error: Modbus address must be an integer 1–247.
 
 ❌ Port Errors : 
 Error: No port selected. Click ⟳ Refresh first.
Connection Error: [SerialException message]
 
 
 Troubleshooting Guide 
 Problem: No Serial Ports Detected 
 Symptoms : 
 
 Dropdown shows "No ports found" or is empty 
 "⟳ Refresh" button doesn't populate ports 
 
 Causes and Solutions : 
 
 
 USB Adapter Not Connected 
 
 ✅ Solution : Plug USB adapter into PC USB port 
 Click "⟳ Refresh" again 
 
 
 
 Driver Not Installed 
 
 ✅ Solution : Install USB-RS485 driver for your adapter chipset 
 Check Windows Device Manager → Ports (COM & LPT) 
 If device shows yellow warning icon, driver missing 
 Download and install correct driver (see Equipment section) 
 Restart PC if required 
 Click "⟳ Refresh" after driver installed 
 
 
 
 Faulty USB Cable or Adapter 
 
 ✅ Solution : Try different USB port 
 Try different USB cable 
 Test adapter on another PC 
 Replace adapter if confirmed faulty 
 
 
 
 Windows Security Blocking 
 
 ✅ Solution : Run converter.exe as Administrator 
 Right-click → "Run as administrator" 
 
 
 
 
 Problem: "No Response" During Protocol Conversion 
 Symptoms : 
 
 Log shows: [HH:MM:SS] ✗ No response. 
 Tool retries with reverse byte toggle automatically 
 
 Causes and Solutions : 
 
 
 Incorrect Station Address 
 
 ✅ Solution : Double-check 12-digit serial number on meter label 
 Ensure no typos (easy to confuse 0/O, 1/I, 6/8) 
 Verify number matches meter (not packaging) 
 
 
 
 Wiring Problem (Most Common) 
 
 ✅ Solution : Check RS485 connections 
 Verify A+ to A+, B- to B- (not swapped) 
 Tighten terminal screws (loose connections cause intermittent failures) 
 Use twisted pair cable (not individual wires) 
 Keep wiring short (<2 meters) 
 
 
 
 Incorrect Baud Rate 
 
 ✅ Solution : Confirm baud rate is 2400 for DLT645 meters 
 Some meters may use different rates (try 1200, 4800) 
 
 
 
 Meter Not Powered 
 
 ✅ Solution : Verify meter LCD is illuminated 
 Check power connections (L/N for single-phase, L1/L2/L3/N for three-phase) 
 Use multimeter to verify voltage at terminals 
 
 
 
 RS485 Bus Termination Issue 
 
 ✅ Solution : If multiple meters on same bus, add 120Ω termination resistor across A+/B- at each end 
 
 
 
 Reverse Byte Order Required 
 
 ✅ Solution : Tool auto-retries with reverse toggle 
 Manually toggle "Reverse address bytes" checkbox and retry 
 
 
 
 Meter Already in Modbus Mode 
 
 ✅ Solution : Meter may already be converted (from previous attempt) 
 Change baud rate to 9600 
 Use "Scan" function to find current address 
 Skip to "Change Modbus Addr" step if needed 
 
 
 
 
 Problem: Scan Finds No Modbus Address 
 Symptoms : 
 
 After protocol conversion, scan completes but finds no meter 
 Log shows: ⚠ No meter responded on Modbus addresses 1-247. 
 
 Causes and Solutions : 
 
 
 Protocol Conversion Failed 
 
 ✅ Solution : Meter still in DLT645 mode 
 Return to "Convert Protocol" step 
 Try manual conversion with longer timeout 
 Power cycle meter (turn off, wait 10 seconds, turn on) 
 Retry conversion 
 
 
 
 Incorrect Baud Rate for Modbus 
 
 ✅ Solution : After conversion, meter uses 9600 baud for Modbus 
 Change baud rate dropdown to 9600 
 Retry scan 
 
 
 
 Meter Needs Time to Restart 
 
 ✅ Solution : Wait 5 minutes after protocol conversion 
 Power cycle meter 
 Retry scan 
 
 
 
 
 Problem: Address Change Fails 
 Symptoms : 
 
 Log shows: ✗ Address change failed. 
 Meter doesn't respond at new address 
 
 Causes and Solutions : 
 
 
 Wrong Register Address for Meter Type 
 
 ✅ Solution : 
 DDSU666 (single-phase) uses register 0x0006 
 DTSU666 (three-phase) uses register 0x002E 
 Converter GUI currently supports single-phase only 
 For three-phase, use CLI version:
 python3 converter_cli.py change --port COM3 --current 1 --target 10 --type 3phase
 
 
 
 
 
 Meter Not in Modbus Mode 
 
 ✅ Solution : Ensure protocol conversion succeeded first 
 Use "Scan" to verify meter responds in Modbus mode 
 
 
 
 Current Address Incorrect 
 
 ✅ Solution : Use "Scan" function to discover actual current address 
 Update "Current Modbus Address" field with scanned value 
 Retry address change 
 
 
 
 
 Problem: Meter Doesn't Respond After Conversion 
 Symptoms : 
 
 Conversion appears successful in log 
 But meter doesn't respond in Modbus mode later 
 
 Causes and Solutions : 
 
 
 Conversion Incomplete (False Positive) 
 
 ✅ Solution : Some meters acknowledge command but don't actually switch 
 Power cycle meter (off for 30 seconds, then on) 
 Wait 5 minutes after power-on 
 Retry scan 
 
 
 
 Firmware Requires Extended Timing 
 
 ✅ Solution : Use CLI version with extended timeout:
 python3 converter_cli.py convert --port COM3 --station 200322016690 --reverse --extended
 
 
 
 
 
 Meter Reverted to DLT645 Mode 
 
 ✅ Solution : Some meters revert to factory default after power loss 
 This is rare but possible 
 Repeat full conversion process 
 Test immediately after conversion before power cycling 
 
 
 
 
 Escalation: When to Contact Development Team 
 Contact Development Team if: 
 
 Meter doesn't respond after 3 conversion attempts 
 Error messages not covered in this guide 
 Physical damage suspected (meter LCD dead, RS485 terminals broken) 
 Firmware version incompatibility suspected 
 Need CLI script for three-phase meter address change 
 converter.exe crashes or freezes 
 
 Escalation Information to Provide : 
 
 Meter serial number 
 Meter type (DDSU666 or DTSU666) 
 Complete log output from converter tool (screenshot) 
 Steps already attempted 
 Observations (LCD displays, unusual behavior) 
 
 
 Safety and Best Practices 
 General Safety 
 ⚠️ Electrical Safety : 
 
 Only qualified electricians perform power wiring (Phase 4) 
 De-energize circuits before connecting meter to live power 
 Use lockout/tagout (LOTO) procedures 
 Verify voltage with multimeter before assuming power is off 
 Wear appropriate personal protective equipment (PPE) 
 
 ⚠️ RS485 Bus Safety : 
 
 Never connect/disconnect RS485 wiring with power applied (can damage meter) 
 Use ESD (electrostatic discharge) precautions when handling meter electronics 
 Keep RS485 bus wiring away from high-voltage conductors (>50V) 
 
 Conversion Best Practices 
 ✅ One Meter at a Time : 
 
 Convert meters individually (don't connect multiple unconverted meters to same bus) 
 This prevents address conflicts during conversion 
 
 ✅ Document Before Converting : 
 
 Update inventory BEFORE starting conversion 
 Record meter serial number, type, and assigned address 
 This prevents confusion if interrupted mid-process 
 
 ✅ Test Before Shipping : 
 
 Always perform Phase 3 Pre-Dispatch Testing 
 Catch issues in lab, not at customer site 
 Reduces field failures and rework 
 
 ✅ Never Reuse Addresses on Same Site : 
 
 Each meter must have unique address 
 Keep site-specific address map 
 Even if meter replaced, don't reuse old address immediately (wait until removed from config) 
 
 ✅ Physical Labeling is Mandatory : 
 
 Label prevents installation errors 
 Field Installation Team relies on label (may not have inventory access) 
 Use durable labels (water-resistant, doesn't fade) 
 
 ✅ Keep Conversion Logs : 
 
 Take screenshot of successful conversion log 
 Store in Nextcloud or local folder 
 Useful for audit trail and troubleshooting 
 Include meter serial number in filename (e.g., conversion_200322016690_success.png ) 
 
 
 Inventory Management 
 Master Inventory Spreadsheet 
 Primary Location : Nextcloud Sheets (shared link - request from Development Team)
 Backup Location : Nextcloud /Field_Operations/Templates/METER_INVENTORY_TEMPLATE.xlsx 
 Required Columns 
 
 
 
 Column Name 
 Data Type 
 Purpose 
 Example 
 
 
 
 
 Meter Serial Number 
 Text (12 digits) 
 Unique meter identifier 
 200322016690 
 
 
 Meter Type 
 Text 
 Single or three-phase 
 DDSU666 or DTSU666 
 
 
 Site Name 
 Text 
 Customer site 
 Office Building A 
 
 
 Building/Customer 
 Text 
 Specific location or customer name 
 Floor 1 Reception 
 
 
 Assigned Modbus Address 
 Number (1-247) 
 Pre-assigned unique address 
 10 
 
 
 Status 
 Dropdown 
 Current workflow stage 
 Assigned, Converted, Shipped, Installed, Commissioned 
 
 
 Date Assigned 
 Date 
 When address assigned 
 2026-04-01 
 
 
 Date Converted 
 Date 
 When protocol conversion completed 
 2026-04-02 
 
 
 Date Installed 
 Date 
 When physically installed at site 
 2026-04-03 
 
 
 Date Commissioned 
 Date 
 When added to NFE config and logging 
 2026-04-04 
 
 
 Converted By 
 Text 
 Field Ops team member name 
 Jane Doe 
 
 
 Installed By 
 Text 
 Field Installation team member 
 John Smith 
 
 
 Commissioned By 
 Text 
 Remote Commissioning team member 
 Alice Johnson 
 
 
 Notes 
 Text 
 Issues, observations, special instructions 
 Required reverse byte toggle 
 
 
 
 Status Workflow 
 Unassigned → Assigned → Converted → Shipped → Installed → Commissioned
 ↓ ↓ ↓ ↓ ↓ ↓
 (New) (Dev Team) (Field Ops) (Field Ops) (Field Inst) (Remote Comm)
 
 Status Definitions : 
 
 Unassigned : New meter received from supplier, no address assigned yet 
 Assigned : Development Team assigned Modbus address, ready for conversion 
 Converted : Field Operations Team completed protocol conversion and address assignment 
 Shipped : Meter packaged and sent to customer site 
 Installed : Field Installation Team physically installed meter and wired to bus 
 Commissioned : Remote Commissioning Team added to NFE config and verified logging 
 
 Conditional Formatting (Nextcloud Sheets) 
 Setup in Nextcloud Sheets : 
 
 
 Status Column Color Coding : 
 
 Unassigned: Gray background 
 Assigned: Yellow background (action required by Field Ops) 
 Converted: Light blue (ready to ship) 
 Shipped: Blue (in transit) 
 Installed: Orange (action required by Remote Comm) 
 Commissioned: Green (complete) 
 
 
 
 Overdue Highlighting : 
 
 If "Status = Assigned" and "Date Assigned" > 7 days ago → Red text (conversion overdue) 
 If "Status = Installed" and "Date Installed" > 2 days ago → Red text (commissioning overdue) 
 
 
 
 Address Range Validation : 
 
 If "Meter Type = DDSU666" and "Assigned Modbus Address" < 10 or > 99 → Red background (invalid) 
 If "Meter Type = DTSU666" and "Assigned Modbus Address" < 100 → Red background (invalid) 
 
 
 
 Data Validation (Nextcloud Sheets) 
 Setup in Nextcloud Sheets : 
 
 
 Status Dropdown : 
 
 Column: Status 
 Criteria: List from a range: Unassigned, Assigned, Converted, Shipped, Installed, Commissioned 
 Reject invalid input 
 
 
 
 Meter Type Dropdown : 
 
 Column: Meter Type 
 Criteria: List from a range: DDSU666, DTSU666 
 Reject invalid input 
 
 
 
 Address Range Validation : 
 
 Column: Assigned Modbus Address 
 Criteria: Number between 1 and 247 
 Warning on invalid input (not rejection, to allow temporary placeholders) 
 
 
 
 Audit Trail Requirements 
 What to Track : 
 
 Every status change must include date and operator name 
 Notes column should capture any deviations from standard process 
 Conversion logs (screenshots) stored in Nextcloud with meter serial in filename 
 
 Retention : 
 
 Keep inventory records for lifetime of deployment 
 Archive old entries when meters decommissioned 
 Export monthly backup to Excel and store in Nextcloud 
 
 
 Future Enhancements 
 Planned for Phase 2 : 
 
 
 Web-Based Commissioning Portal 
 
 Browser-based UI for adding meters to NFE config 
 No SSH required for Remote Commissioning Team 
 Authentication and audit logging 
 Real-time dashboard showing meter status 
 
 
 
 Automated Meter Discovery on Modbus Bus 
 
 Raspberry Pi scans bus for new meters automatically 
 Suggests config entries for detected meters 
 Reduces manual configuration errors 
 
 
 
 Inventory Management Database 
 
 Centralized database replacing Nextcloud Sheets 
 API integration between converter tool and inventory 
 Auto-update status on successful conversions 
 Real-time sync across all teams 
 
 
 
 Converter Tool Enhancements : 
 
 Batch operations (convert multiple meters in sequence) 
 Save/load meter assignment lists 
 Auto-populate from inventory database 
 Persistent configuration (remember last settings) 
 Auto-generated conversion reports (PDF) 
 
 
 
 Mobile App for Field Installation 
 
 Scan meter barcode/QR code 
 Verify address label matches inventory 
 Guided installation checklist 
 Photo documentation for audit trail 
 
 
 
 Automated Alerting : 
 
 Notify Remote Commissioning when meter installed 
 Alert if meter stops logging after commissioning 
 Daily summary of meters pending action 
 
 
 
 Fleet Management Dashboard : 
 
 Web dashboard showing all meters across all sites 
 Real-time status (online/offline) 
 Energy consumption graphs 
 Maintenance scheduling 
 
 
 
 How to Request Features : 
 
 Contact Development Team (CTO) 
 Describe use case and priority 
 Features prioritized based on team feedback and ROI 
 
 
 Appendix 
 Glossary 
 
 DL/T645 : Chinese national standard for electrical meter communication protocol 
 Modbus RTU : Industry-standard serial communication protocol for industrial devices 
 RS485 : Differential serial communication standard (A+/B- or Data+/Data-) 
 Station Address : 12-digit unique identifier for DL/T645 meters (meter serial number) 
 Modbus Slave Address : 1-byte address (1-247) for Modbus devices on same bus 
 USB-RS485 Adapter : Device converting USB to RS485 differential signals 
 Baud Rate : Communication speed in bits per second (bps) 
 Protocol Conversion : One-time operation switching meter from DL/T645 to Modbus mode 
 ZeroTier : Virtual private network (VPN) software for secure remote access 
 SSH : Secure Shell protocol for remote command-line access 
 
 Quick Reference Card 
 Converter Tool Quick Steps : 
 
 Connect meter power and USB-RS485 adapter 
 Run converter.exe → Refresh → Select port → Connect 
 Enter 12-digit station address (from meter label) 
 Enter target Modbus address (from inventory) 
 Click "▶ Full Process" 
 Wait for "✓ Full Process Complete" 
 Update inventory status to "Converted" 
 Label meter with address sticker 
 
 Common Mistakes to Avoid : 
 
 ❌ Using address 1 (always use 10+ for single-phase, 100+ for three-phase) 
 ❌ Swapping A+/B- wiring (causes "No response" errors) 
 ❌ Forgetting to change baud rate to 9600 after conversion (for Modbus scan) 
 ❌ Skipping physical label (causes installation errors) 
 ❌ Not updating inventory (breaks audit trail) 
 
 
 Document Version History : 
 
 v1.0 (2026-04-04): Initial release - Complete pre-commissioning workflow 
 
 Document Owner : Development Team
 Review Cycle : Quarterly or as needed for process updates