Overview of the PMS Bolt Load Cell
The BoltSafe PMS (Periodic Monitoring System) bolt load cell is a specialized load sensor designed to periodically monitor bolt load in bolted joints. It allows real-time checks with the use of a handheld reader and probe, eliminating the need for cables through a non-contact inductive interface. This technology provides accurate bolt load readings, enhancing structural safety and reliability while reducing costs in installation and maintenance.
How the PMS Bolt Load Cell Works
Each PMS load sensor is equipped with an ASIC (Application-Specific Integrated Circuit) that handles signal processing and digital communication. Every load cell has a unique serial number for tracking and identification. The system not only measures bolt load but can also monitor sensor temperature, supporting precise load assessments. The load cell is available in both standard stainless steel and a high-strength variant that handles 15% more load without increasing size.
Applications in Structural Health Monitoring
The PMS load cell also serves as a washer in temporary constructions or structural health monitoring, helping to verify load levels and prevent structural failures. Available in sizes from M30 to M64 and 1-1/4” to 2-1/2”, the sensor sits on the non-driven side of the joint, preferably under a nut. When the bolt is tightened, it applies force to the load cell washer, causing minor deformation that alters electrical resistance. These changes allow for real-time load monitoring in demanding environments, including exposure to oil, seawater, extreme weather, and temperatures between -40°C and 80°C.
Advantages of Periodic Monitoring with PMS Load Cells
The PMS load cells are ideal for confined spaces where cables are impractical. Because the system is cable-free and reads data through a probe, users can conveniently monitor multiple sensors with the same handheld reader in sequence. The handheld reader can store data from up to 256 load cells, and measurements can be transferred to a computer for further analysis.
Compatible Readout Methods for PMS Load Cells
The PMS load cell requires the SM-200 handheld reader and PMS probe for data acquisition. The probe collects data through infrared by touching the sensor, which powers the load cell and retrieves the measurements through a non-contact interface. The handheld reader can be connected to a PC via USB to transfer data using “Report Generator” software, simplifying data storage and analysis.
