Vibrating Wire Strain Data Logger

The data logger handles vibrating wire strain gauges with a frequency range spanning 400 Hz to 4000 Hz, which covers the majority of foil-type strain gauges and common embedment gauges used in concrete. It uses a pluck excitation method that avoids overheating the coil on dense measurement schedules. The input accuracy is built around a time-interval measurement resolution of 0.05 µs, translating to better than 0.1 Hz resolution under stable temperature. This matters when you’re looking for microstrain changes in a rock mass over months. Storage-wise, the logger records timestamped frequency and temperature readings on a removable SD card. Most configurations allow 2 million or more data points before cycling. For power, you can run it off a 12V battery or a small solar panel — standard in remote monitoring stations. Communication options include RS-485 and optional 4G for sites where you need daily data pushes to a server. Kingmach keeps the protocol open, so you’re not locked into a single software platform. One detail often overlooked: the logger’s input channel isolation. When you connect multiple gauges, crosstalk can mask small strain signals. We separate each channel with opto-isolated front ends and a guarded switching matrix. This isn’t unique, but we’ve seen installations where cheap multiplexers corrupted data. Our design has been validated in multi-point borehole extensometer setups where all gauges share a common cable bus, and still maintain the stated resolution. Finally, physical build: a die-cast aluminum housing rated IP66 for direct burial or wall mounting. The terminal strips accept 2.5 mm² wires with captive screws, and the labeling is large enough to read in a trench with a headlamp. If your project has custom requirements — say, a different sensor excitation voltage or an extra relay output — we often modify the firmware and hardware within a few weeks.