Pressure Regulator Setting

[Instnapp]

Hi Good Day,

I have a 535H pressure regulator with a bench range setting from 2-10 PSI.Can I be able to set at the regulator at the low end 2PSI setting OR would its repeatability be affected?

Appreciate your feedback.

 

[EmmanuelTop]

Someone correct me if I am wrong, but regulator accuracy depends on the actual flow, not on the mechanical set pressure. As the flow increases, the droop (= offset from the set point) increases and the actual regulated pressure decreases.

Dejan IVANOVIC
Process Engineer, MSChE

 

[danw2]

Correct, regulated pressures drops off with increasing flow. Droop is inherent with a proportional only mechanical regulator.

Make sure that the regulated output pressure is set at a 'working' flow rate. An output adjustment at zero flow rate will bump to a different level when flowing.

 

[EmmanuelTop]

Instnapp, you can refer to B.Liptak's "Instrument Engineer's Handbook Vol.2 - Process Control and Optimization", Chapter 7.7 Pressure regulators. It provides the formula for calculating set point offset as a function of flow.


Dejan IVANOVIC
Process Engineer, MSChE