JUMO 202755/20, Руководство по эксплуатации

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3 Inductive conductivity measurement
8
3.2 Function
of the
transmitter The transmitter has been designed for use on site. A rugged housing protects
the electronics and the electrical connections from corrosive environmental
conditions (IP67 enclosure). As standard, the device has one analog signal
output each for conductivity/concentration and temperature respectively.
Further processing of the standard signals can take place in a suitable display/
control device, or, for example, directly in a PLC.
The output signals are electrically isolated from one another and from the
medium.
of the
measuring cell The conductivity is measured using an inductive probe. A sinusoidal a.c.
voltage feeds the transmitting coil. Depending on the conductivity of the liquid
to be measured, a current is induced in the receiver coil. This current is
proportional to the conductivity of the medium. The cell constant of the
inductive probe depends on its geometry. The cell constant can also be
affected by components in the immediate vicinity.
(1) Temperature sensor, exposed (1a) optionally:
internal temperature sensor
(2) Measuring cell body in PP (3) Measurement coils
(4) Liquid loop
(2)
(1)
(3)
(4)
(1a)