AFRISO KP EX Series, Руководство по эксплуатации

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Selection criteria
EN
RF ... EX / KP ... EX / PF ... EX
5.3.3 Ambient temperature
The accuracy information shown on the dial applies to an ambient tempe-
rature of +20 °C. Different temperatures have an influence on the
accuracy; the influence depends on the measuring system.
According to EN 837-1, a deviation of the indication caused by tempera-
ture influences is permissible up to the following value with reference to
the full scale value:
• Bourdon tube pressure gauges: 0.04 %/K
• Capsule pressure gauges: 0,06 %/K
• Diaphragm pressure gauges: 0.08 %/K
1. Protect the pressure gauge from atmospheric influences in outdoor
applications in order to avoid freezing of the product at temperatures
below 0 °C.
The viscosity of the filling liquid in products with liquid filling increases at
decreasing temperatures. This causes a considerable delay in indication.
5.3.4 Corrosive atmosphere
1. In the case of a corrosive atmosphere, use suitable housings and
assemblies made of resistant materials, for example, special surface
treatments.
5.4 Overload
Overloads cause tension in the elastic measuring element which decreases
its services life and deteriorates the measuring accuracy.
1. Use products whose full scale value is greater than the maximum static
pressure.
- The product is less sensitive to overload and load changes.
2. Install an overpressure safety device if, for operational reasons, the range
must be smaller than the maximum operating pressure.
3. Use products whose full scale value is greater than the maximum differen-
tial pressure.