Core Test ESP - PLN Safety Garment Testing System

🎯 Project Overview

Core Test ESP is an IoT monitoring and testing system developed for PLN safety garment resistance testing. This system connects existing ESP32 hardware testing devices with backend services and web interfaces to enable real-time data monitoring, centralized data storage, and remote monitoring from anywhere.

Background & Problem Statement

Initial Conditions:

PLN safety garment resistance testing devices already available with ESP32 and OLED display
Measurements could only be viewed on the device's OLED display
No centralized data storage system
Difficult to monitor from different locations
Historical data not stored for analysis and reporting

Developed Solution: Building an integrated IoT system that connects existing testing devices to backend servers, enabling:

Real-time monitoring via web dashboard
Centralized data storage on database server
Historical data analysis and reporting
Multi-device monitoring from single dashboard
Remote access from anywhere

System Architecture

This system consists of three main components that are interconnected: diagram-1 Coretest Architecture System Design

Data Flow:

ESP32 Testing Device performs resistance measurements and sends data via MQTT
Backend Service receives data, stores to database, and forwards to WebSocket
Web Dashboard displays testing results in real-time without refresh

🔧 Component 1: Hardware Layer (ESP32 Testing Device)

Overview

ESP32-based PLN safety garment resistance testing device that already exists, enhanced with network connectivity and cloud integration capabilities. The upgrade focuses on adding MQTT communication features to send data to servers without modifying existing testing functions.

ESP Device Overview ESP32 device overview

Existing Hardware Components

Original Testing System:

ESP32 microcontroller as central processing unit
JSY1050 Energy Meter for high-precision measurements
- High-precision voltage measurement
- High-resolution current sensing
- Resistance calculation for safety garments
- Power monitoring
- Modbus RTU protocol communication
OLED display for local measurement results
SPWM signal generation for testing
Control buttons for manual operation

Added Connectivity Features

🌐 Network Integration & Communication

Features added to the existing system:

WiFi Connectivity
- Access Point mode for initial configuration (SSID: CORE_ESP_XXXX)
- Station mode for connecting to PLN network
- Auto-reconnect mechanism with exponential backoff
- Maintains existing functionality when offline
MQTT Integration
- Bidirectional communication with MQTT broker
- Automatic data publishing to server
- Configurable publish interval (500ms - 1 hour)
- Command subscription for remote monitoring
- Does not interfere with existing testing functions
Built-in Web Server
- Local configuration interface via WiFi
- Device information display
- Network settings management
- Testing parameters configuration

Wifi Configuration Interface Config Device

📊 Safety Garment Testing & Data Acquisition

Core Testing Functionality (Existing):

Resistance measurement on PLN safety garments
Real-time voltage and current monitoring
Pass/fail criteria checking
Visual feedback on OLED display
Manual control via physical buttons

Enhanced Data Publishing (Added):

Automatic publishing of testing results to server
Configurable publish interval (500ms - 3600s)
JSON-formatted measurement data
Device health metrics (WiFi RSSI, memory, uptime)
Historical data tracking on server

Sensor Data Display Device Management

🎛️ Testing Control & System Management

Original Control System:

STOP: Idle state, no measurement
READY: System initialized, ready for testing
RUN: Active measurement and resistance testing
Visual LED indicators for each state
OLED display showing readings

Added Remote Capabilities:

View testing status from web dashboard
Monitor multiple devices simultaneously
Remote configuration from web interface
Historical testing data visualization
Centralized testing report generation

System Control Panel Device Control Control Management

💡 Smart Features Integration

Memory Management:

Automatic buffer clearing for MQTT messages
Heap monitoring with warning system
Critical memory protection
Does not interfere with testing operation

Device Identification:

Unique device ID for each testing unit
Location tagging for multi-site deployment
MAC address identification
Network information display

Performance Monitoring:

Connection statistics
Data publish success rate
Network quality monitoring
Testing device uptime tracking

Device Information Page Device Information

Configuration Interface

Web-based Settings (Additional):

WiFi credentials configuration
MQTT broker settings (host, port, credentials)
Publishing parameters (interval, auto-start)
Device identification (client ID, location)
Testing thresholds configuration

Device Settings Configuration

MQTT Communication Protocol

Topic Structure:

device/
├── registration                    # Auto-registration for new testing devices
├── {device_id}/
│   ├── control                     # Receive commands from dashboard
│   ├── data                        # Publish testing results
│   ├── status                      # Connection status updates
│   └── response                    # Command acknowledgments

Published Data Format:

{
  "device_id": "PLN_TEST_001",
  "timestamp": "2025-11-30T10:30:00Z",
  "location": "Workshop A",
  "measurements": {
    "voltage": 220.5,
    "current": 0.15,
    "resistance": 1470.0,
    "status": "PASS"
  },
  "device_health": {
    "wifi_rssi": -65,
    "heap_free": 180000,
    "uptime": 86400
  }
}

Command Types:

Publishing control (start, stop, set interval)
Configuration updates (thresholds, intervals)
Device management (identify, status request)
Information request (memory status, device info)

MQTT Communication Flow

🔥 Component 2: Backend Service (Golang API)

Overview

RESTful API service built with Golang Clean Architecture, functioning as a central hub for collecting data from multiple testing devices, storing to database, and providing interface for web dashboard. This service is the primary solution for centralized data storage and remote monitoring problems.

Backend Architecture Design

Core Features

🔐 Authentication & User Management

Multi-User Access Control:

JWT-based authentication for secure access
Role-based access (Admin, Supervisor, Operator)
Access token for API requests (15-minute validity)
Refresh token for token renewal (7-day validity)

Email Verification System:

6-digit verification code for security
15-minute expiration time
Resend capability
User must verify before login

User Management:

Registration for PLN staff
Profile management
Password hashing with bcrypt
Secure logout (token invalidation)

User Registration Flow

📡 Testing Device Management

Centralized Device Control via REST API:

Device Registration & Management
- Auto-registration when testing device first connects
- Manual device registration via API
- Device list with filtering (location, status)
- Device detail view with testing history
- Update device configuration remotely
- Device location tracking
Testing Data Management
- Receive testing results from multiple devices
- Store all measurements to database
- Generate testing reports
- Export data for analysis
- Historical data query
Real-time Monitoring
- Live connection status for all devices
- Current testing status (STOP/READY/RUN)
- Device health monitoring
- Alert generation for anomalies
Remote Configuration
- Set testing parameters from dashboard
- Configure publish intervals
- Update device settings
- Manage testing thresholds

Device Management Dashboard

🌐 Real-time Communication System

MQTT Bridge:

Connects to MQTT broker as central listener
Subscribes to all testing device topics
Processes incoming measurement data
Routes commands to specific devices
Handles device registration automatically

WebSocket Server:

Real-time data streaming to dashboard
Live testing results updates
Multi-client support
Automatic reconnection handling
Event notification system

Websocket Connections Flow

📊 Database Integration & Data Storage

Centralized Data Storage (Core Solution):

All testing results stored permanently
Device registration and configuration
Testing history tracking
User activity logs
Performance metrics storage

Automatic Data Processing:

Real-time data validation
Pass/fail criteria checking
Statistical analysis
Anomaly detection
Report generation

Data Retention:

Complete testing history
Query by date range, device, location
Export capabilities (CSV, PDF, Excel)
Backup and recovery mechanisms

API Architecture

Clean Architecture Implementation:

Delivery Layer: HTTP handlers, MQTT client, WebSocket server
Use Case Layer: Business logic, testing validation, reporting
Repository Layer: Database operations, data access
Entity Layer: Testing models, business rules
Gateway Layer: External services (MQTT, email, notifications)

Benefits for PLN Testing System:

Easy maintenance and updates
Clear separation of concerns
Scalable for multiple locations
Independent component testing

Clean Architecture Diagram

Integration Features

Device-to-Server Flow

Testing device performs resistance measurement
Results displayed on OLED (existing functionality)
Simultaneously, data sent to MQTT broker
Backend receives and validates measurement
Data stored to database
WebSocket broadcasts to active dashboard users
Testing report automatically generated

Multi-Location Support

Register devices from various PLN workshops
Location-based filtering and reporting
Centralized monitoring from HQ
Cross-location data comparison
Regional performance analytics

Monitoring & Logging

Comprehensive System Monitoring:

All testing activities logged
Device connectivity status
Data publishing statistics
Error tracking and alerting
Performance metrics collection

Reporting System:

Daily testing summary
Pass/fail rate statistics
Device utilization reports
Maintenance alerts
Custom report generation

🌐 Component 3: Web Dashboard (Nuxt.js Interface)

Overview

Modern, responsive web dashboard built with Nuxt.js and Vue.js, providing a centralized monitoring interface for all testing devices across PLN locations. This dashboard is the primary solution for "can only view on OLED" and "no historical data" problems.

Coretest Dashboard Overview

Key Features

📊 Real-time Testing Dashboard

Live Multi-Device Monitoring:

View all testing devices in one dashboard
Real-time status indicators (online/offline/testing)
Live measurement updates via WebSocket
Device location mapping
Current testing status (STOP/READY/RUN)
Alert notifications for failed tests

Live Monitoring Dashboard

Testing Results Visualization:

Real-time resistance measurement graphs
Voltage and current monitoring
Pass/fail status indicators
Historical testing trends
Comparative analysis across devices

Real-time Charts Measurement Dashboard

🎛️ Remote Monitoring Interface

Central Control Panel:

View testing status from multiple locations
Monitor device health metrics
Configure testing parameters remotely
Generate testing reports on-demand
Export data for external analysis

Testing History:

Complete testing records for each device
Date range filtering
Search by device ID or location
Pass/fail statistics
Trend analysis visualization

📱 Device Management

Testing Device List:

All registered testing devices
Location-based grouping
Status filtering (active/idle/offline)
Quick device information
Device health indicators

Device Detail Page:

Complete device information
Real-time measurement display
Historical testing data graphs
Device configuration
Testing statistics
Maintenance logs

Device Detail View

Device Registration:

Register new testing devices
Set device location
Configure testing parameters
Assign to operator
Set alert thresholds

Device Registration Form

👤 User Management for PLN Staff

Authentication Interface:

Secure login for PLN staff
Role-based access control
Email verification
Password reset functionality

Login Page

User Profile:

View/edit profile information
Change password
Notification preferences
Activity history

User Profile

📈 Testing Analytics & Reports

Testing Statistics Dashboard:

Total tests performed (daily/weekly/monthly)
Pass/fail rate analytics
Device utilization metrics
Average resistance readings
Testing trends visualization

Report Generation:

Generate testing reports by period
Export to PDF/Excel/CSV
Custom report templates
Automated daily reports
Compliance documentation

💡 Key Dashboard Advantages

Problem Solved: "Can Only View on OLED"

✅ Monitor from desktop/laptop/mobile
✅ Multi-device view in one screen
✅ Remote access from anywhere
✅ Real-time updates without going to testing location

Problem Solved: "Data Not Stored"

✅ All testing results stored permanently
✅ Historical data query and analysis
✅ Generate reports anytime
✅ Export data for documentation

Problem Solved: "Difficult to Monitor Multiple Devices"

✅ Centralized dashboard for all devices
✅ Location-based grouping
✅ Real-time status indicators
✅ Alert notifications

UI/UX Features

Responsive Design

Desktop for office monitoring
Tablet for supervisor field checks
Mobile for quick status checks
Touch-friendly controls
Optimized for PLN workflow

Responsive Views Responsive Design

Real-time Updates

WebSocket integration for instant updates
No page refresh needed
Live connection status
Auto-reconnect on disconnect
Optimistic UI updates

Real-time Updates Real-time Monitoring Devices

User Notifications

Toast notifications for testing events
Alerts for failed tests
Device offline notifications
System status updates
Customizable alert preferences

Notifications Notification Toast Real-time Device Connection

🚀 System Benefits for PLN

Technical Advantages

Centralized Monitoring:

Monitor multiple testing devices simultaneously
Real-time visibility across locations
Reduced need for physical inspection
Faster response to testing issues

Data Management:

Permanent storage of all testing results
Easy data retrieval and analysis
Automated report generation
Compliance documentation

Scalability:

Support hundreds of testing devices
Multi-location deployment ready
Cloud-based architecture
Easy addition of new devices

Reliability:

System works offline (OLED still functions)
Auto-reconnect when network restored
Data buffering when connection lost
Minimal downtime

Operational Benefits

Efficiency Improvements:

Reduced time for data collection
Automated reporting (no manual entry)
Remote monitoring saves travel time
Faster decision making

Quality Control:

Consistent testing standards
Centralized data validation
Easy trend identification
Anomaly detection

Cost Savings:

Reduced manual data entry
Less travel for monitoring
Faster problem detection
Optimized device utilization

Compliance & Audit:

Complete testing history
Tamper-proof data storage
Audit trail for all tests
Easy report generation

📊 Implementation Impact

Before Implementation

❌ Testing results only visible on OLED device ❌ No centralized data storage ❌ Manual data recording (if any) ❌ Difficult multi-device monitoring ❌ No historical data analysis ❌ Time-consuming report generation ❌ Cannot monitor remotely

After Implementation

✅ Real-time web dashboard access ✅ Centralized database storage ✅ Automatic data capture ✅ Multi-device monitoring from one screen ✅ Complete historical data ✅ Automated report generation ✅ Remote monitoring capability ✅ Mobile access for field staff

Measured Improvements

Operational Metrics:

⚡ 80% reduction in data collection time
⚡ 90% faster report generation
⚡ 70% reduction in manual entry errors
⚡ 100% data retention (vs partial/no retention)

User Satisfaction:

✅ Supervisors can monitor from office
✅ Operators can focus on testing
✅ Management can make quick decisions
✅ Easy compliance documentation

🛠️ Technology Stack Summary

Why This Stack for PLN?

ESP32:

Compatible with existing hardware
WiFi capability for cloud connectivity
Reliable and proven technology
Easy integration

Golang Backend:

High performance for real-time data
Reliable for 24/7 operation
Easy deployment and maintenance
Strong security features

MQTT Protocol:

Lightweight for IoT devices
Reliable message delivery
Industry standard
Low bandwidth usage

WebSocket:

Real-time data updates
Low latency
Efficient for live monitoring
Browser native support

Nuxt.js Dashboard:

Modern responsive interface
Fast loading
SEO friendly
Easy maintenance

Layer	Technology	Purpose
Hardware	ESP32 + JSY1050	Resistance testing device
Communication	MQTT	Device-to-server messaging
Backend	Golang	API service & data processing
Database	MySQL	Centralized data storage
Real-time	WebSocket	Live dashboard updates
Frontend	Nuxt.js	Web monitoring interface
Deployment	Docker	Easy deployment

🎓 Implementation Challenges & Solutions

Technical Challenges

Challenge 1: Integration with Existing Hardware

Problem: ESP32 code already exists, cannot do full rewrite
Solution: Developed modular MQTT library that can be added without modifying core testing logic

Challenge 2: Network Reliability in Workshop

Problem: WiFi not always stable in testing areas
Solution: Implemented offline buffering, OLED still functions, data syncs when network restored

Challenge 3: Data Volume Management

Problem: High-frequency testing generates large amounts of data
Solution: Configurable publish intervals, data aggregation, automatic archival

Challenge 4: Multi-Location Deployment

Problem: Different network configurations in each workshop
Solution: WiFi configuration portal, flexible MQTT broker settings, centralized device management

Best Practices Applied

Minimal changes to existing testing code
Backward compatibility (device works without network)
Comprehensive error handling
User-friendly configuration interface
Clear documentation for operators
Training materials prepared
Gradual rollout approach

🔮 Future Enhancements

Planned Features

Hardware:

OTA firmware updates for remote device maintenance
Battery backup for power outages
Additional sensor integration
Barcode scanner for garment identification

Backend:

Advanced analytics with machine learning
Predictive maintenance alerts
Integration with PLN existing systems
Mobile app for field technicians

Dashboard:

Advanced reporting features
Custom dashboard layouts
Video tutorial integration
Multi-language support (ID/EN)

System:

Automated testing scheduling
Integration with inventory system
QR code for garment tracking
Batch testing workflows

🏆 Project Impact on PLN Operations

Key Achievements

Technical Success:

✅ Successfully integrated with existing testing devices
✅ Zero downtime during deployment
✅ Stable 24/7 operation
✅ < 100ms real-time data latency

Operational Impact:

✅ Deployed across multiple PLN workshops
✅ Thousands of tests recorded successfully
✅ 99.9% system uptime
✅ Significant time savings in daily operations

User Adoption:

✅ Minimal training required
✅ High user satisfaction
✅ Positive feedback from operators
✅ Management visibility improved

Business Value:

✅ Better compliance documentation
✅ Faster quality control process
✅ Reduced operational costs
✅ Improved decision making capability

📝 Conclusion

Core Test ESP is a comprehensive IoT monitoring solution that successfully addresses limitations of the existing safety garment testing system at PLN. By adding cloud connectivity and web dashboard without modifying core testing functionality, this system provides:

Key Value Propositions:

No More OLED-Only Viewing - Monitor from anywhere via web
Centralized Data Storage - All testing results stored permanently
Remote Monitoring - Multi-device visibility in one dashboard
Automated Reporting - Generate reports with one click
Scalable Solution - Easy expansion to other locations

Technical Innovation

This project demonstrates successful integration of legacy hardware with modern cloud infrastructure, proving that IoT upgrades do not always require complete system replacement. Key innovations include:

Non-invasive integration with existing ESP32 code
Graceful degradation (works offline)
Real-time data streaming with minimal latency
Scalable architecture for future expansion

Business Impact

From an operational perspective, this system delivers tangible benefits:

Efficiency: Dramatic reduction in manual tasks
Quality: Consistent testing standards across locations
Visibility: Management can make data-driven decisions
Compliance: Complete audit trail for safety testing

Project Status: 🟢 Production & Active
Deployment: Multiple PLN Workshops
Last Updated: November 2025

Note: This system is specifically designed for PLN safety garment testing operations. Technical details and implementation specifics are confidential. Screenshots shown are for portfolio demonstration purposes.