Load sensors: Capacitive load sensor features USB output
While not one of the big four process variables (pressure, flow, temperature, and level), load sensors can be very useful in process plants. For example, placing load sensors under the feet of a tank or reactor can provide one of the simplest and most accurate level measurement approaches there is. The new iLoad sensors from Loadstar provide a means of digital load and force measurement that incorporates integrated computing and communication via USB output.
The iLoad digital sensor is reportedly the first capacitive load sensor with USB output, designed to plug directly into a PC, enabling users to measure loads, forces or weights without need for any additional signal conditioning, data acquisition, or special software. The sensor appears as a virtual COM port on a PC enabling a user to read data directly using simple ASCII commands with any terminal emulator, such as HyperTerminal. Or, Loadstar offers LoadVue Lite software that takes care of all communication functions and displays loads in pounds, kilograms, or Newtons.
If an analog output is required, there is the iLoad analog sensor which is built on the same platform as the digital version but designed to interface directly to a PLC using a linear, 0.5-4.5 V dc output proportional to applied loads. No amplification or signal conditioning is required because all electronics are built into the self-contained integrated sensor.
The iLoad Series is available in 10, 50, 100, 250, and 500 lb capacities to measure compressive and tensile loads with accuracies of 0.25% to 0.025% of full scale loads. Higher capacities up to 15,000 lb are available as a special order.
—Edited by Peter Welander, process industries editor, PWelander@cfemedia.com , Control Engineering Weekly News