Selection Criteria; Pressure Surges - Afriso Rf Ex Serie Betriebsanleitung

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Selection criteria

UNSUITABLE PRODUCT
• Only use pressure gauges which are suitable for the actual operating condi-
tions (for example, measuring range, ambient conditions, medium, materials,
overpressure safety).
• Verify that the selection criteria as per EN 837-2 as well as all directives,
standards and safety regulations pertaining to the application of the pressure
gauge are adhered to.
Failure to follow these instructions can result in death, serious injury or
equipment damage.
5.1 Range
Select the range in such a way that the maximum pressure load does not
exceed 75 % of the full scale value in the case of static load and 65 % of the
full scale value in the case of dynamic load.
- This prolongs the service life of the product (as per EN 837-2).
5.2 Properties of the medium
5.2.1

Pressure surges

Pressure surges must not exceed the application range of the products.
The measuring element must not be subjected to pressure surges or sud-
den pressure changes. Such changes considerably reduce the service
life of the product. For example, pressure surges occur if the product is
mounted to a pump, as indicated by major oscillations of the pointer.
Reduce such pressure surges by installing a damper or an overload
protection device between the pressure source and the elastic measur-
ing element.
Throttle elements considerably reduce the inlet cross section which leads
to a delay of the pressure change in the measuring element. The suscep-
tibility to dirt is a disadvantage of such arrangements.
Damping elements at the movement delay the pointer motion and cause
increased wear of the movement.
Liquid filling causes a damping of the measuring element and decreases
the wear of the moving parts.
Selection criteria
WARNING
RF ... EX / KP ... EX
EN
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