High end stable variometer for geomagnetic observatory use.
General description
The danish produced magnetometer has proven its stability for many years and is now being produced by DTU Space.
20 FGE magnetometers have been running in Greenland, many on remote islands, for more than 20 years.
More than 200 magnetometers of this kind are installed at observatories worldwide.
The fluxgate magnetometer type FGM-FGE is suitable for digital recording of the magnetic field at observatories and in the field.
The main idea has been to construct a reliable and very stable instrument that is easy to set up and operate. In order to avoid drift due to tilt of the instrument pier, which is often the main cause of baseline drift, a special version of the magnetometer is available in which the sensors are suspended by two crossed bronze bands to compensate for the tilt.
The FGM-FGE magnetometer has analog outputs enabling the user to adapt the instrument to their own data logging systems. An optional build-in AD-converter is also available.
Features
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3 linear core sensors mounted on a marble cube for good mechanical stability.
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Compensation coils on quartz base for highest temperature stability.
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Highly stable digitally controlled compensation of main field. Very good long-term stability.
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Nonmagnetic electronics which may be placed close to the sensor head in a temperature controlled room to avoid any temperature drift.
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2 built-in temperature sensors.
Optional features
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Battery operation. 10-18 VDC, 3 W
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Build-in 16 bit AD-converter (Adam module)
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Extension sensor cable up to 100 meter
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Low temperature (-30 °C) version of suspended magnetometer
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Non-suspended version is available
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Spare Magnetometer electronic FGE, works with all old versions of the FGM-magnetometer
Specifications
|
Analog output: |
±10V |
|
Dynamic range: |
User specified (100-1000 nT/Volt) |
|
Resolution: |
0.1 nT |
|
Compensation field range: |
+-64 000 nT |
|
Compensation field steps: |
150 nT |
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Misalignment of sensor axis: |
< 2 mrad |
|
Long time drift: |
< 3 nT/year |
|
Temp. coeff. of sensor: |
< 0.3 nT/°C |
|
Temp. coeff. of electronics: |
< 0.1 nT/°C |
|
Temperature resolution: |
0.1 °C |
| Band pass: |
DC to 1 Hz |
Spec. of optional suspension
| Range of compensation: |
± 0.5° |
| Factor of compensation: |
> 200 |
General information
Size of non-suspended system:
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300 x ø270 mm 9.5 kg |
Size of suspended system:
|
550 x ø270 mm 20 kg |
Size of electronics:
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160x90x360 mm 3.0 kg |
Power requirements:
|
230 VAC, 3W |
| Operating temperature: |
0 to 60°C |
Responsible:
Lars W. Pedersen