Smart Hopper Monitoring System

How the System Works

The Smart Hopper Monitoring System combines a radar level sensor, an analog acquisition module, an IoT gateway, and a relay output module to control a bucket elevator automatically.

1. A radar level sensor measures hopper fill level continuously and sends a 4 to 20 mA analog signal
2. An analog acquisition module reads that signal and passes it to the IoT gateway over Modbus RTU (RS485)
3. The IoT gateway processes the data, displays it on its dashboard, and sends control signals to the relay output module
4. The relay output module starts or stops the bucket elevator based on high-level and low-level thresholds: high level stops the elevator, low level starts it

Level Sensor

Rocksensor Radar RLT6900L, Lens Antenna

• Continuous, non-contact level measurement for bulk solids in dusty environments
• Uses 80 GHz FMCW radar for level measurement
• Resolution: 1 mm
• Accuracy: plus or minus 5 mm
• Range: up to 120 m
• Protection rating: IP67
• Lens antenna generates a focused radar beam
• Swivelling antenna holder allows optimized sensor alignment
• Air purge provision maintains reliable measurement under dusty conditions
• Isolated transmit and receive signals enable full-range measurement with minimal dead zone

IoT Gateway (With Integrated HMI)

Primary features:

• 10.1-inch industrial HMI based on the Raspberry Pi CM4 platform
• 12 to 24V DC supply, 2 USB 2.0 ports, digital I/O
• Cloud connectivity through WiFi, 4G LTE, and Ethernet
• Industrial communication interfaces, including Modbus serial (RS485) and Ethernet

Key functions:

• Displays real-time hopper levels
• Processes sensor and relay logic
• Logs process data locally
• Supports remote monitoring and configuration

Dashboard

Key features:

• Configurable upper and lower thresholds
• Relay action mapping
• Automatic reset conditions
• Real-time hopper visualization with live level indication
• Configurable hopper dimensions

The dashboard splits into a Configuration UI, where thresholds and relay actions are set, and a Visualization view, showing hopper diagrams, current fill levels, process min and max ranges, high and low limits, and live bucket elevator status for both the main hopper and the mixer hopper.

Historical Data

The system logs a real-time hopper level trend for each hopper, plotting material level against time with high-level (HL) and low-level (LL) threshold lines clearly marked, so operators can review fill and drain patterns over time rather than relying on memory or spot checks.

Why It Matters

Intelligent Automated Level Control:

• Continuous monitoring
• Real-time visibility
• Automatic material handling
• Reduced downtime
• Scalable architecture