Principle; Notes On Electromagnetism; The Emitter; The Receiver - Chauvin Arnoux LOCATO 110 Mode D'emploi

Notes on electromagnetism

An electrical current of intensity (i) passing through a conductor creates
a magnetic field (H) surrounding this conductor throughout its length.
The magnitude (H) of this magnetic field is proportional to the value of
this current (i).
A coil picking up this magnetic field (H) will therefore supply a strong
signal if:
- The current (i) is strong
- The coil is close to the conducting wire
NB : - According to the direction of the current (i) passing through the
wire, the magnetic field (H) turns in one direction or the other.
- The magnetic fields (H) of two currents (i) in opposing directions
cancel each other out.
This is the case for example in supply and return wires which are in the
same cable, or placed in parallel, side by side, in an installation.
The LOCAT Emitter
Connected to a live circuit, the Emitter creates a current at a specific
frequency Fe = 3500 Hz.
This current generates a magnetic field of the same frequency Fe
throughout the path of the current.
The LOCAT Receiver
This Receiver identifies, locates the conductor being traced by means of
the magnetic field picked up by its frequency Fe.
The Receiver contains a sensor sensitive to the magnetic field. It is very
selective, which means it is only sensitive to this particular frequency Fe.
When measuring the intensity of the magnetic field, it indicates in fact the
proximity of the corresponding conductor. By moving the Receiver in front
of a group of cables, a connecting terminal or a set of circuit breakers, the
one which supplies the Emitter can quickly be found because the frequency
current Fe is passing through it and the Receiver gives its strongest
reading when close to it.

The advantages

The advantages follow from its operating principle and are numerous.
- The most important is that identification by the Receiver is at a distance
(up to 3 m approx.) and even through a wall (up to 50 cm thick).
- The current of frequency Fe cannot spread to cables other than those
of the direct supply circuit of the Emitter.
- This current of frequency Fe is the same all through the supply circuit,
therefore finding the cables with the Receiver is as easy at 100 metres
from the Emitter connection as at 1 metre.
- The specifications of the pulsed current (5 mA at 3500 Hz) are such that
there is no risk of magnetic disturbance of even very sensitive electronic
equipment. For example, the radiation created is quite negligible by
comparison with that of a domestic dimmer switch.

PRINCIPLE

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