Smartec CLD18

2

Endress+Hauser

Function and system design

Measuring principle

Inductive conductivity measurement

An oscillator (1) generates an alternating magnetic field in the primary coil (2), which induces a

current flow (3) in the medium. The strength of the current depends on the conductivity and thus on

the ion concentration in the medium. The current flow in the medium, in turn, generates a magnetic

field in the secondary coil (4). The resulting induced current is measured by the receiver (5) and used

to determine the conductivity.

1

5

4

3

2

A0004894

 1

Inductive conductivity measurement

1

Oscillator

2

Primary coil

3

Current flow in the medium

4

Secondary coil

5

Receiver

Advantages of inductive conductivity measurement:

• No electrodes and therefore no polarization effects

• Accurate measurement in media with a high degree of pollution and a tendency to form buildup

• Complete galvanic isolation of the measurement and the medium

Input

Measured variables

Conductivity

Temperature

Measuring range

Conductivity:

Recommended range: 200 μS/cm to 1000 mS/cm

(uncompensated)

Temperature:

–10 to 130 °C (14 to 266 °F)