Specifications
Current
Range |
10 kA -
1000 kA (Other range upon request) |
Accuracy |
+/- 1% (< 0,1% for
high current range) |
Components |
Sensor
as a buffered speciality fiber;
Laser diode and detector;
Electronic slide-in card for computer;
Analog output of +/- 5V;
Other options upon costumer request |
Applications
- Electricity research laboratories
- Electric power stations
- Electric power industry
- Plasma current research
- Field trials
Technical Background
The motivation for developing a product based on
fiberoptic was to have a contactless
current measurement device with wide frequency response, which is not
subject to
electromagnetic interference or high voltage problems.
Faraday-Effect
The plan of
polarisation of linearly polarised light traversing a medium
is rotated by the magnetic field component along the direction of
light
propagation.
If the sensing fiber completely surrounds a net current I the
Farraday effect rotation F can be written F = n V I,
where n is the number of fiber turns and V the
Verdet constant in appropriate units 4.7 10-6
rad/Ampere.
In optical fibers to get a
high accuracy in measurement of polarisation rotation is greatly
complicated by the changes in the state of polarisation of the light
probageting through the fiber, because of the inavitable presence of the
birefringence in the fiber. The elemination of this Distortions in a speciality fiber is the
innovation of the product. |