Nuclear Belt Scale
The Model 500 Nuclear Belt Scale uses gamma radiation to measure the weight and flow rate of bulk materials on conveyor belts — accurately and without contact.
Turn belt weight data into better throughput decisions
Know your tonnage in real time
Continuous mass flow data for train and barge loading, stockpile management, and production reporting — without stopping the belt.
Catch process upsets immediately
See feed rate deviations as they happen — not after a shift report reveals a problem.
No contact, no downtime
Non-contact measurement means no wear, no maintenance windows, and no interruptions to material flow.
Applications
Coal
In coal mines and power plants, the Model 500 provides continuous, accurate mass flow measurement on conveyor belts. Real-time weight data supports train and barge loading, stockpile management, blending operations, and plant efficiency reporting — all without interrupting material flow.
Cement, Minerals, & Other Products
The Model 500 is used in cement manufacturing, mineral processing, sand processing, and household waste recycling to monitor raw material feed rates and finished product throughput. Its non-contact design eliminates maintenance issues common with mechanical belt scales in dusty, abrasive environments.
Mining & Minerals
In mining operations, the Model 500 provides continuous mass flow measurement of ore, concentrate, and tailings on conveyor belts — supporting production reporting, stockpile management, and process control without contact with the material.
Biomass & Waste-to-Energy
The Model 500 measures bulk material weight in biomass and waste-to-energy facilities, providing accurate feed rate data for combustion control and regulatory reporting.
Case Study
Capital Sand — Frac Sand Processing
Capital Sand installed ETI Model 500 Nuclear Belt Scales on multiple conveyor belts at their frac sand processing facility. The non-contact design handles the abrasive, high-silica environment without the wear and maintenance issues common with mechanical belt scales — delivering continuous, accurate mass flow data for production reporting and loadout management.
View all case studiesKey Benefits
How It Works
The scale operates on the principle of gamma energy attenuation. A sealed radioactive source and detector are mounted across the conveyor. The radiation passes through the material and is measured below the belt. An industrial computer processes these signals and displays real-time weight data.
Dual Gamma Sources
Two sealed radioactive sources are mounted to the conveyor frame: a low-energy Am-241 source and a high-energy Cs-137 source. Both irradiate the full material stream on the belt simultaneously.
Material Attenuation
Gamma energy is attenuated as it passes through the bulk material. The degree of attenuation is proportional to the areal density — mass per unit area — of the material on the belt.
Scintillation Detection
A scintillation detector mounted below the belt senses the transmitted gamma energy and converts it to electrical signals for processing.
Signal Processing
An industrial computer processes the detector signals, applying calibration factors to convert the attenuation measurement into accurate weight-per-unit-length readings.
Real-Time Display
Processed weight data is displayed numerically and graphically in the operator interface and output to plant control systems via analog connections or direct database access.
Source and detector assembly across an operating conveyor belt
Gamma attenuation measurement through the conveyor stream
Technical Specifications
U.S. Patent # 7,243,414B2
System Components
The analyzer system consists of:
- Model 500 Single-Gamma Analyzer (SGA)Fixed nuclear gauging device using sealed radioactive sources (one to three energy sources depending on application). Source shield mounts above the conveyor belt and collimates a conical fan radiation beam through the material. A radiation energy-sensitive detector mounts in the beam path below the belt. Weight: 350 lbs. (159 kg). Not compatible with PVC or steel-reinforced conveyor belts — belt specifications must be reviewed prior to installation.
- Model 900 Data Acquisition Unit (DAU)NEMA 4 electronics enclosure with fully digitized data acquisition and control electronics, UPS, detector temperature control and monitoring, I/O modules, circuit breakers, and managed network switch. Wall-mountable. Dimensions: 36 in. H × 30 in. W × 13 in. D (91 × 76 × 33 cm). Weight: 170 lbs. (77 kg). Max cable run to analyzer: 328 ft. (100 m).
- Interconnecting CablingComplete set of signal cables, power cables, and special connectors between the SGA and DAU. Maximum cable length: 328 ft. (100 m).
- ETI DataView Software PackageMonitors all aspects of the analyzer: spectral shape, count rate, resolution, dead time, detector temperature, belt speed, DAU temperature, calibration parameters, and final data. View data from 3-second measurements to daily totals with configurable tabular and graphical displays.
Measured Parameters
- Material Weight
- Mass Flow Rate
Data Outputs
- Analog Outputs4 channels, configurable for 0–20 mA or 4–20 mA signals
- Digital Outputs4 channels, configurable for 24 VDC signals
- Modbus TCP/IPStandard industrial communication protocol
- SQL DatabaseDirect database access for Plant Information systems
Plant Integration
Readings are taken every 3 seconds and averaged over 60 seconds. Output is available via analog connections or direct database access for seamless integration into plant control systems. ETI DataView client software provides real-time dashboards, historical trending, and batch reporting on any plant workstation.
Data Outputs
- Analog Outputs4 channels, configurable for 0–20 mA or 4–20 mA signals
- Digital Outputs4 channels, configurable for 24 VDC signals
- Modbus TCP/IPStandard industrial communication protocol
- SQL DatabaseDirect database access for Plant Information systems
ETI DataView showing real-time belt weight measurements with user-selectable time period averages alongside a continuous trend chart.
One year of service included
Every ETI system ships with one full year of support — unlimited phone, email, and remote VPN access, plus one scheduled site visit for inspection, calibration, and NRC-required leak tests.
Ready to optimize your process?
Contact our engineers to discuss how this analyzer can improve your operation.