LEMI-036

Product type:
Intermagnet 1-second standard flux-gate magnetometer

Product description:
High resolution and precision
Low noise level
Guaranteed low time shift of the acquired data
Low temperature offset
Convenience of installation and service
Automatic operation control
Satellite synchronization
RS – 422 output
IAGA2002 formatted 1-sec and 1-min data
Deep suppression of the power mains interference
3 years operational guarantee

Application description:
Fluxgate magnetometer (FGM) LEMI-036 was specially developed for the super-sensitive measurements of 3 components of Earth magnetic field induction and their variations per the new 1-second INTERMAGNET standard. The signals with periods from 1 to 100.000 seconds and more may be collected with a reasonable error. In order to realize this design, major attention was paid to such principal FGM characteristics and parameters as frequency response and sampling synchronization accuracy as well as thermal and temporal stability and noise level. To fulfill such mutually contradictory requirements as a speed of response and deep suppression of industrial noise, the specific combination of analog and digital filters was realized in this instrument. The magnetic sensor of fluxgate type, which mainly determines magnetometer stability and noise level, was manufactured with high-tech glass ceramics having close to zero thermal expansion factor using well-proven technology, which implements recent findings in the excitation circuit construction and operation mode. Using the best available voltage references and passive components provides excellent stability of the FGM electronics.

This FGM can be installed into empty boreholes with a diameter of 0.2 m and more. The fluxgate sensor is fixed at the suspended platform to automatically keep the horizontal level.
The instrument operates with an external computer, which controls magnetometer operation and stores acquired data. Communication between a computer and LEMI-036 is provided by the RS-422 digital interface. The instrument has a GPS receiver for data sampling synchronization and FGM location coordinates determination.

Highlights:
Low noise

Product image:

Specifications:

• Measured range of magnetic field variations: ±4000 nT
• (with analogue outputs available)
• Automated offset compensation band along each magnetic component: ± 70000 nT
• Resolution along each component
• in the 1-second and 1-minute data files: 0.01 nT
• in the 0.1-second file: 0.001 nT
• Temperature drift: < 0.5 nT/°C
• Frequency band: DC-3.5 Hz
• Output noise in frequency band (0.01 – 1) Hz: < 0.01 nT rms
• Magnetic sensor components orthogonality: < 30 min of arc
• Range of sensor tilt compensation:< 8 deg of arc
• Sampling rate
• at the magnetometer digital output: 10 per second
• after PC software digital filtration: 1 per second
• 1 per minute
• Error of synchronization with UTC time: < 10 ms
• Digital output: RS 422
• Analogue outputs：Single-ended, ± 4V
• GPS timing and co-ordinates determination
• Operating temperature range： -5 to +40°C
• Power supply：12 V
• Power consumption：<4 W
• Physical dimensions
• sensor：160×360 mm
• electronic unit：402x160x91 mm
• Weight
• Sensor with cable：6.9 kg
• Electronic unit with power supply/interface test cable：3.9 kg
• GPS antenna with test cable and support：0.8 kg
• Cables
• Sensor cable：up to 50 m

Additional Information: