Description
The d-GMM is a single channel Ground Movement Monitor available with high resolution and data accuracy.
The microcontroller provides linearization, temperature compensation and outputs an ASCII encoded RS485 signal digital signal. Output signals can be transmitted over 250m/900ft without distortion. Each instrument is individually calibrated to ensure that the resolution (<0.01mm) and accuracy (0.25% typical) are an order of magnitude better than for similarly priced technology.
The digital form of the signals eliminates the necessity for expensive analog-to-digital conversion and results in low cost monitoring peripherals that output data in real world units (mm and degC). The instrumental is fully compatible with d-Logger, d-Mesh and d-Reader and can be networked using the IoT gateway.
Specifications
| Borehole size | 30mm+ |
| Core Technology | Magnetostrictive displacement sensor |
| Output Signal | RS485 serial (9600,8,N,1) ASCII-encoded digital signal |
| Stroke (F.S.) | 145mm, 250mm |
| Displacement Resolution | 0.01mm with handheld readout |
| Displacement Linearity | Typically 0.25% F.S. |
| Displacement Accuracy | Better than=/- 0.5mm |
| Temperature Range | -40 to 125 degrees Celsius |
| Temperature Accuracy | +/- 2oC –Digitally trimmed at 0oC and 25oC |
| Temperature Resolution | Temperature Resolution: 0.1oC |
| Temperature coeff for eddy current sensor: | <0.01%FS/oC (0-50oC) |
