Data loggers are designed to measure static strain, a phenomenon where the subject strain does not change at all or slowly changes. As seen in load tests of large scale structures, static strain is often measured in several hundred channels and under dozens of load conditions. Data loggers are available in 2 types: stand-alone and PC-controlled. Both are oriented to automatic multi-channel measurement as intelligent, expansible systems. A data logger can stably measure micro-volt signals in strain/stress measurement indoors and outdoors.
Besides that advantage, some recently developed data loggers have a processing capability incorporated into the portable package. Advancements in electronic components, progress in multimedia in information-related fields and downsizing of equipment have generated the following demands:
- Simultaneous measurement of various static variables including strain/stress, load, pressure, acceleration, displacement, torque, voltage and temperature
- Visual presentation of the progressive status of measurement and function that enables smooth progression of measurement while accepting the engineer's judgment.
- Unattended measurement
- More compact and lightweight design
- Capability to measure not only static phenomena but also events changing at a frequency of several Hz
- Efficient measurement and data collection through Internet or Ethernet LAN