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Direction for Use (GB) / Gebrauchsanleitung (D)
Converter
CON 011
Direction for use
The demodulator at the output of the oscillator generates a low
−
frequent signal from the
amplitude modulated HF– signal. The following units serve the purpose of linearization and
amplification of the signal. The output connectors OUT and
⊥
provide a signal proportional to
the actual distance between sensor head and target material.
1.3
Installation and Comissioning
1.3.1
Hints for installation and connection
To ensure the electromagnetic compatibility of the eddy current measuring chain, we
recommend using double screened twisted pair cable for connecting the signal converter to the
measuring amplifier. For direct connections to the converter, cables of type LiYCY – CY
2x2x0,25 mm
@
should preferably be used. Master connection cable may be any multicore cable
with a corresponding cable structure. We recommend to connect the outer screen of the cable
to protective earth/measuring ground close to the measuring amplifier directly at the cable inlet
of the control cubicle. Moreover, the outer screen of the cable should be connected to protective
earth as often as possible i.e. at every intermediate distribution frame or cable gland.
An extremely high electromagnetic compatibility can be achieved by connecting the cable
screen to protective ground at either side of the cable – provided that no compensating current
goes over the screen. The signal converter CON 011 is provided with a specific cable gland M16
which allows proper connection of the screen to the CON housing, see Fig 5 and Fig 7. In case
of high disturbances it might be useful to connect the screen only to the housing of the CON.
The internal cable screens must be fed through the cable glands of the CON and then precisely
cut off, refer to the wiring scheme Fig 7. In the control cubicle, close to the measuring amplifier,
the screen has to be connected to 0V / common. Connection of the wires is to make according
to Fig 5.
In case that only cables of type LiYCY
−
CY 2x2x0,25mm
@
are used, the maximum cable length
is 400m, if longer cables are used an intermediate distributor must be set close to the converter
and cables with a higher cross section used for connection to the measuring amplifier (e.g.
LiYCY
−
CY n x 2 x 1,5 mm
@
).
•
Measuring cables have to be installed according to general standards for measuring and
control cables and, if possible, in metallic cable channels or tubes. It must be observed that
the measuring cables are arranged orthogonally.
•
Close CON housing carefully and observe the correct position of the rubber sealing ring.
•
At special applications, where high static discharges(> 6kV) could occur, it must be checked
whether the ground connection via the mounting screws are sufficient. In this case it could
be useful to connect the CON housing to protective earth with an extra cable.
1.3.2
Inherently safe installation
On the following conditions, the sensors PR 6422 ... PR 6426 together with the CON 011 signal
converter may be used for applications in hazardous areas for zone 0, protection class
”Inherently safety” – EEx ia IIC T6 :