METALLIC TIME DOMAIN REFLECTOMETRY (TDR) SYSTEM
- Description
- Characteristics
- Solutions
-
METALLIC TIME DOMAIN REFLECTOMETRY (TDR) SYSTEM
Metallic Time Domain Reflectometry (TDR) System is a simple and economical way of detecting and interpreting rock and soil mass response to underground and surface mining using coaxial cables grouted in boreholes. TDR can be used effectively to locate rock and soil mass movements.
TDR involves the installation of a coaxial cable in a borehole filled with grout that matches existing soil or rock conditions. A TDR unit is employed to generate a voltage pulse along the cable and receive reflections. Reflections are generated by cable deformations, abrasions and severing. Crimps at known locations along the cable are used to provide depth datum.
As movement occurs, the reflections along the cable change as the cable deforms. By connecting the TDR200 to a PC through Type A Micro B USB cable, TDR reflections can be interpreted by software, thereby inferring location, type and rate of earth movement. TDR systems can be combined with data loggers and multiplexers to allow remote readings of multiple cables.
-
Technical specifications
- Tensile Strength 113 kg
- Maximum Tensile Force 1100 N (247 lbf)
- Minimum Bending Radius, Single Bending 50.8 mm (2 in.)
- Minimum Bending Radius, Repeated Bending 127 mm (5 in.)
- Bending Moment 3.8 Nm (33.633 lb-in)
- Installation Temperature -40 to +60 °C (-40 to 140 °F)
- Operation Temperature -55 to +85 °C (-67 to 185 °F)
- Storage Temperature -70 to +85 °C (-94 to 185 °F)
- Inner Conductor Copper-Clad Aluminium Wire, 4.8 mm (0.19 in.)
- Dielectric Foam Polyethylene, 12.9 mm (0.51 in.)
- Outer Conductor Corrugated Copper, 13.9 mm (0.55 in.)
- Jacket Material Polyethylene, PE 15.8 mm (0.62 mm)
- Weight 0.22 kg/m (0.148 lb/ft)
- Characteristic Impedance 50 ± 1 Ω
- Relative Propagation Velocity 88%
- Capacitance 78 pF/m (23.1 pF/ft)
- Inductance 0.19 μH/m (0.058 μH/ft)
- Maximum Operating Frequency 8.8 GHz
- Jacket Spark Test RMS 8000 V
- Peak Power Rating 40 kW
- DC Resistance, Inner Conductor 1.48 Ω/km (0.451 Ω/1000ft)
- DC Resistance, Outer Conductor 2.69 Ω/km (0.82 Ω/1000ft)
-
The vibrating wire piezometer is precisely used for:
- Monitoring rock and soil movement
- Monitoring subsidence above abandoned underground mines
- High wall slope monitoring in open pit mines
- Determination of cable fault location, i.e. distance to fault
Leave a request — we will find
a solution for your facility
We will contact you, discuss the details and find a format
that is mutually beneficial.