BARTINGTON INSTRUMENTS
Page 5 of 8
OM3836/2
• Ensure that the cables are shielded to prevent them picking up electromagnetic
interference.
• The cable shield should be connected to power supply ground at the power supply end
(either through the connector body, or by connecting the shield to the power ground
wire).
• The connecting cable to the sensor should be a five-core screened cable. Two cores will
be used for positive and negative power supply lines, one core for output signal, one
core for signal common, and one for power supply ground.
5.2. Connection to Power Supply/Acquisition Unit
Caution:
When providing your own power supply, do not exceed the voltage rating, provide
sufficient current, and ensure correct polarity is respected, see
DS3836
.
Caution:
Connect the Mag646 electronics board before the supply is energized, as this
prevents high surge currents which could cause damage.
Note:
Apply the positive and negative supplies simultaneously, and avoid leaving the
electronics board connected to one polarity only.
The analogue output of the sensors as well as the power supply connectors are available on the
outline drawing
DR2945
.
Where no Bartington power supply or acquisition unit is used, some basic recommendations for
integration of the sensor are available in
AN0042
.
6. Using the Mag646
6.1. Mag646 Operation
Once the electronics is fully connected to both sensor head and power supply/acquisition unit,
the supply can be switched on. The sensor will provide an analogue output which is proportional
to the field measured. Please refer to
DS3836
for the sensor’s scaling factor.
Testing of the sensor’s response can be done, as an example, by moving the sensor in the Earth’s
field and ensuring that the signal varies in relation to orientation. In the horizontal plane, a
minimum value is obtained when the axis is in the magnetic East-West direction, and maximum
when pointing Magnetic North.