Wartung/Maintenance
12
4.3
Manufacturer's certificate
This is to certify that the measuring instrument
has been radio interference-suppressed in accordance with the regulations as decreed
in the Official Journal BMPT 243 / 1991 with supplement 46 / 1992 and EN 55 011.91=
DIN VDE 0875, part 11, k 07.92 an d EN 50 081-1
The German Post Office was advised that this instrument has been brought into circulation
and was granted the right to inspect the series for conformance with the regulations.
5.
Maintenance
5.1
Maintenance notes
When the measuring cell CLS 51 is used for
media separation in CIP applications, the risk
of surface soiling is very low since the conti-
nuous change from base to acid and vice ver-
sa does not permit coatings to form.
5.2
Testing notes
For simulation purposes, a wire loop is threa-
ded through the centre hole in the sensor.
The simulation resistance (a single resistor or
a decade resistor) is then connected to this
wire loop.
(Hier fehlt die engl.Übersetzung)
Refer to the following table for the simulation
resistances to be used for the different con-
ductivity ranges.
The simulation resistance for intermediate va-
lues can be calculated using the following for-
mula:
1
R =
⋅ k
conductivity
Conductivity in S / cm produces R in Ω
Conductivity in mS / cm produces R in kΩ
Conductivity in µS / cm produces R in MΩ
k (cell constant) = 6
CLS 51
Display /
measuring range
120 µS / cm
240 µS / cm
600 µS / cm
1200 µS / cm
2400 µS / cm
6 mS / cm
12 mS / cm
24 mS / cm
60 mS / cm
120 mS / cm
240 mS / cm
600 mS / cm
1200 mS / cm
Note:
The display value matches the simu-
lation value only if:
• the temperature is 25 °C or
field V1 / H0 has been selected for
measured value display (display
in V1 / H0);
• if precision resistors with a toler-
ance of 0.1 % are used for simula-
tion;
• if the contact resistances of the
wire loop and soldering joint are a
part of the permissible tolerance.
CLS 51
Simulation
resistance
50 kΩ
25 kΩ
10 kΩ
5 kΩ
2.5 kΩ
1 kΩ
Ω
500
Ω
250
Ω
100
Ω
50
Ω
25
Ω
10
Ω
5