Piezoelectric detector upper casing 1.5-meter cable

Structure of the piezoelectric geophone

A piezoelectric geophone converts mechanical vibrations (seismic waves) into electrical signals through the inverse piezoelectric effect of a piezoelectric crystal (such as quartz or piezoelectric ceramic). Its typical structure includes:

Upper casing: Protects the internal piezoelectric element, usually made of metal (such as aluminum alloy) or engineering plastic, with waterproof, dustproof, and impact-resistant properties;

Cable: Connects the upper casing to the signal acquisition equipment, transmits electrical signals, and provides mechanical fixation for the geophone.

1.5-meter cable specifications

Length: 1.5 meters (customizable length, adjustable according to exploration needs);

Conductor: Multi-stranded tinned copper wire (cross-sectional area usually 0.1~0.5 mm²), excellent conductivity, and oxidation resistance;

Insulation layer: Polyethylene (PE) or polyvinyl chloride (PVC), wear-resistant, and good insulation;

Shielding layer: Aluminum foil or copper mesh shielding, anti-electromagnetic interference (EMI), improves signal purity;

Sheath: Polyurethane (PU) or rubber, waterproof, oil-resistant, and bend-resistant, suitable for outdoor environments.

Function and role

1. Signal transmission

Connects the geophone's upper casing to ground acquisition equipment (such as a seismograph), stably transmitting the weak electrical signals (microvolt level) generated by the piezoelectric crystal to the backend circuit;

The 1.5-meter length is suitable for near-surface high-density exploration (such as urban shallow geological surveys), avoiding signal attenuation (voltage drop caused by cable resistance) and noise introduction caused by long cables.

2. Mechanical fixation and protection

The cable can be fixed to the ground surface using clamps, cable ties, etc., to prevent the geophone from shifting due to external forces (such as wind or human touch), ensuring the accuracy of signal acquisition;

The waterproof sheath protects the internal wires, preventing short circuits caused by humid environments (such as swamps or post-rain construction scenarios).

3. Anti-interference design

The shielding layer suppresses electromagnetic interference in urban environments (such as power lines and communication signals), improving the signal-to-noise ratio (SNR);

Low capacitance design (cable capacitance <50pF/m) reduces high-frequency signal loss, suitable for high-frequency seismic wave (such as >100Hz) detection.

Application scenarios

1. Urban engineering exploration

Underground cavity detection: Detecting karst caves and goafs under urban roads and building foundations. The 1.5-meter cable supports dense deployment of geophones (such as spacing of 1~2 meters), improving lateral resolution;

Subway/pipeline survey: Short-distance cables avoid signal delays between the geophone and acquisition equipment, accurately locating shallow stratigraphic interfaces (such as bedrock depth and thickness of loose sedimentary layers).

2. Environmental vibration monitoring

Monitoring the intensity of vibrations generated by urban construction (such as pile driving and blasting), assessing the impact on surrounding buildings. The 1.5-meter cable facilitates the placement of geophones close to the vibration source;

When used with wireless acquisition equipment, the short cable can be directly connected to nodal seismographs (such as the SmartSolo series), simplifying the wiring process.

3. Earthquake early warning and microseismic monitoring

Deploying geophone arrays in seismically active areas. The 1.5-meter cable reduces the impact of cable weight on the geophone coupling effect, improving the ability to capture weak first arrival waves (P-waves).