Spectre d-GMM
The Spectre d-GMM is a single-channel Ground Movement Monitor from Yieldpoint that uses a magnetostrictive displacement sensor to track borehole rock deformation, with a digital RS485 output.
- Range
- Stroke (F.S.): 145 mm or 250 mm
- Output
- RS485 serial (9600, 8, N, 1), ASCII-encoded digital signal
- Borehole size
- 30 mm+
Overview
In detail
How it works
An on-board microcontroller runs Yieldpoint's d-Tech signal processing, providing linearization and temperature compensation before outputting an ASCII-encoded RS485 digital signal in real-world units (mm and °C). Each instrument is individually calibrated, and the digital signal removes the need for analog-to-digital conversion, keeping the peripheral cost down.
Output signals can be transmitted up to 250 m / 900 ft without distortion.
Connectivity
The d-GMM is fully compatible with d-Logger, d-Mesh and d-Reader, and can be networked using the IoT gateway.
Reach out and say hi
Let us help. Tell us the site, the range you expect and what it has to talk to, and we’ll work out the right variant, cable and mounting — and quote it.
Specifications
Technical specifications
- Borehole size
- 30 mm+
- Core technology
- Magnetostrictive displacement sensor
- Output
- RS485 serial (9600, 8, N, 1), ASCII-encoded digital signal
- Range
- Stroke (F.S.): 145 mm or 250 mm
- Resolution
- 0.01 mm with handheld readout
- Displacement linearity
- Typically 0.25% F.S.
- Accuracy
- Better than ±0.5 mm
- Operating temperature
- -40°C to 125°C
- Temperature accuracy
- ±2°C, digitally trimmed at 0°C and 25°C
- Temperature resolution
- 0.1°C
- Temperature coefficient (eddy current sensor)
Related
Often specified alongside
ESS Earth
Resistance Wire Extensometer RWE
- Application
- Underground hard rock and coal mine displacement monitoring
- Monitoring points
- Pillars, stope walls, roof
Geosystems
JM Series Vibrating Wire Jointmeter
- Range
- 25, 50, 100, 150, 200, 250, 300 mm (200/250/300 mm not available for JM-E)
- Accuracy
Ready to specify?
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