Ground Plane/Surface Current Type Magnetic Field (B-Dot) Sensors

Ground Plane/Surface Current Type Magnetic Field (B-Dot) Sensors

Description

PRODYN ground plane/surface current type magnetic field sensors can be used as a B-DOT sensor or to measure the time rate-of-change of surface current density because the magnetic field over a conductive sheet is related to surface current density.

The sensors consists of a half-cylinder loop on a base plate that when mounted to a conducting surface produces a voltage output in response to a time variant B field. Each sensor has a parallel-series wiring configuration that cancels the electric field induced signals and makes the sensor’s output signal the result of only the magnetic field. The equation pertinent to this device when used as a B-Dot sensor is provided on the datasheet.

Points to Note:

  • Axial v radial: sensors are available with axial or radial output.
  • BS series v B series:  a smaller sensor base plate facilitates mounting and connector placement on the BS series.  Otherwise these are identical.
  • Purging: each sensor is equipped for purging with a gas such as dry air, nitrogen or SF6.
  • Power: an external power source is not required since each sensor is a passive device

 

Model B-15 (up to 300 K rad)

The PRODYN Model B-15 B-Dot current probe was designed to measure current in an intense radiation field (up to 300 K rad). The B-15 has two identical loops with opposite polarity to allow signals to be added, thus providing common-mode rejection capability. Accuracy in manufacturing produces consistent results of better than 5%. Other body styles with different hole patterns are available.

Prodyn B15 free-field magnetic field sensor

 Equivalent Area (Aeq)Frequency Response (3 dB Point)Maximum Output (peak)Output ConnectorMass
B151.7 x 10-6> 500 MHz> 400 V100 Ω Twinax (modified GR-874)43 g

Model BS25 (high frequency)

The PRODYN Model BS25 is a half loop high frequency sensor.  The loop area is encapsulated to provide breakdown resistance and protection from the environment.

Prodyn BS25 ground plane magnetic field sensor

 

 Equivalent Area (Aeq)Frequency Response (3 dB Point)Risetime (tr 10-90)Maximum Output (peak)Output Connector
BS254.5 x 10-611 GHz<0.032 ns± 500 V RMSSMA (Male)

 

MODELS BS40, BS50, BS70 & BS80

These precision high frequency multi-gap type ground plane sensors are designed to measure the time rate of change of surface current density or as a B-Dot sensor. The sensor consists of a half-cylinder loop on a base plate that when mounted to a conducting surface produces a voltage output in response to a time variant B-field. The sensors have a parallel-series wiring configuration that cancels the electric field induced signals and makes the sensors output signal the result of only the magnetic field.

Prodyn BS40-BS80 B-Dot magnetic field sensors

 Equivalent Area (Aeq)Frequency Response (3 dB Point)Risetime (tr 10-90)Maximum Output (peak)Output Connector
BS401 x 10-2> 230 MHz< 1.5 ns± 5 kVType N Female
BS501 x 10-3> 700 MHz< 0.5 ns± 5 kVType N Female
BS701 x 10-4> 1.8 GHz< 0.2 ns± 1.5 kVSMA Female
BS801 x 10-5> 5 GHz< 0.07 ns± 100 VSMA Female

Models B30, B40, B50, B70(r) & B80(r)

PRODYN ground plane/surface current type magnetic field sensors can be used as a B-DOT sensor or to measure the time rate-of-change of surface current density because the magnetic field over a conductive sheet is related to surface current density.

The sensors consists of a half-cylinder loop on a base plate that when mounted to a conducting surface produces a voltage output in response to a time variant B field. Each sensor has a parallel-series wiring configuration that cancels the electric field induced signals and makes the sensor’s output signal the result of only the magnetic field. The equation pertinent to this device when used as a B-Dot sensor is provided on the datasheet.

Points to Note:

  • Axial v radial: sensors are available with axial or radial output.
  • BS series v B series:  a smaller sensor base plate facilitates mounting and connector placement on the BS series.  Otherwise these are identical.
  • Purging:-each sensor is equipped for purging with a gas such as dry air, nitrogen or SF6.
  • Power: an external power source is not required since each sensor is a passive device

 

Model B-15 (up to 300 K rad)

The PRODYN Model B-15 B-Dot current probe was designed to measure current in an intense radiation field (up to 300 K rad). The B-15 has two identical loops with opposite polarity to allow signals to be added, thus providing common-mode rejection capability. Accuracy in manufacturing produces consistent results of better than 5%. Other body styles with different hole patterns are available.

Prodyn B15 free-field magnetic field sensor

Edit
B15
Equivalent Area (Aeq) 1.7 x 10-6 m²
Frequency Response (3 dB Point) > 500 MHz
Maximum Output (peak) > 400V
Output Connector 100Ω Twinax (modified GR-874)
Mass 43g

Model BS25 (high frequency)

The PRODYN Model BS25 is a half loop high frequency sensor.  The loop area is encapsulated to provide breakdown resistance and protection from the environment.

Prodyn BS25 ground plane magnetic field sensor

Edit
BS25
Equivalent Area (Aeq) 4.5 x 10-6 m²
Frequency Response (3 dB Point) 11GHz
Risetime (tr 10-90) <0.032ns
Maximum Output (peak) ± 500V RMS
Output Connector SMA (male)

 

MODELS BS40, BS50, BS70 & BS80

These precision high frequency multi-gap type ground plane sensors are designed to measure the time rate of change of surface current density or as a B-Dot sensor. The sensor consists of a half-cylinder loop on a base plate that when mounted to a conducting surface produces a voltage output in response to a time variant B-field. The sensors have a parallel-series wiring configuration that cancels the electric field induced signals and makes the sensors output signal the result of only the magnetic field.

Prodyn B30-B80R B-Dot magnetic field sensors

 Equivalent Area (Aeq)Frequency Response (3 dB Point)Risetime (tr 10-90)Maximum Output (peak)Output ConnectorMass
B301 x 10-1> 78 MHz< 4.5 ns± 5 kV50 Ω GR-87426 kg
B401 x 10-2> 230 MHz< 1.5 ns± 5 kVType N Female4.5 kg
B501 x 10-3> 700 MHz< 0.5 ns± 5 kVType N female2.7 kg
B70(R)1 x 10-4> 1.8 GHz< 0.2 ns± 1 kVFemale SMA80 g
B80(R)1 x 10-57.5 GHz< 0.045 ns± 250 VFemale SMA15 g

Datasheets