Shielding - Delphin Expert Logger Manual

Expert Logger
. Earth loops can however occur between the sensors of different channels
of a module.
To avoid such loops, we recommend the use of earth-free sensors or sig-
nal sources.
Potential differences
See also
Measuring device—computer earth loop
Most of the device's interfaces are galvanically isolated towards each other
and towards the central device. The earth loop through the communication
circuit as shown in the example does not occur with this device.
Use these interfaces to connect the device to PCs, PLCs or to other man-
ufacturers' equipment.
Galvanic isolation
See also

6.4 Shielding

Measurement signals can be disrupted by the occurrence of magnetic and
electric fields in the measuring circuits, for example generated by neigh-
bouring current-carrying circuits. Shielded cables should therefore always
be used for sensor circuitry and kept at least 50 cm away from other cur-
rent-carrying circuits.
The smaller the sensor signal and/or the higher the sensor impedance, the
more important good shielding becomes for a low noise, accurate reading.
To prevent
example).
a) Sensors without earth
Earthing of the shield is in this case one-sided and directly at the device
(PE connection on the power supply).
See also Earthing.
b) Sensors with earthing
Delphin Technology AG
.
earth loops
, earth the shield on one side of the circuit only (see
.
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Expert Logger Manual
Januar 2018