RMS Engineering

1. Introduction

To give the best performance, KROHNE pressure transmitters must be installed in a correct way. Important instructions should be taken into consideration. In this article we will explain the installation instructions for Differential Pressure Transmitter OPTIBAR DP-7060.

The article cover the following topics:

• General installation guidelines
• Installation with Manifolds
• Installation with capillary
• Measurement Setup For Flow Measurements
• Measurement setup for level measurement

2. General installation guidelines

• Before mounting of the device, please check the correct position of the high (H) and low (L) pressure side. You can see the designations (H / L) in the figure below.
• The process connections of the differential pressure transmitter are usually 1/4-18 NPT (female) at a distance of 54 mm / 2.13". Through optional oval flange adapters the connections 1/2-14 NPT (female) are also selectable.

3. Installation with Manifolds

Manifolds allow for easy installation and commissioning of the transmitter. They separate the device from the process side and ensure simple control of the measuring point. They are available as 3-way and 5-way versions. The integrated equalize valve allows pressure equalization between the high (H) and low (L) pressure side during commissioning. With the manifold, it is possible to disassemble the differential pressure transmitter without interrupting the process. This means higher system availability and even simpler commissioning or maintenance purposes. The 3-way manifold with double-sided flange adapters allows a mechanically robust connection between the differential pressure transmitter and, for example, the impulse lines or the flange adapters of a averaging pitot tube. With a 5-way manifold, two additional valves allow to blow out of the impulse lines and the calibration of the differential pressure transmitter in place.

4. Installation with capillary

•  Avoid using capillary with applications that require longer lengths of capillary to facilitate the installation like tall tanks and vessel, resulting in head temperature effects that are often too great to “tune” out.
  

5. Measurement Setup For Flow Measurements 

- Gases and Liquids with solids content:

• Include the pressure tapping points above or to the side on the process line.
• The device must be mounted above the chosen tapping point.

  - Vapours and Pure Liquids:

• Include the pressure tapping points to the side on the process line.
• The device must be mounted at the same height or underneath the tapping points. 
• In steam applications, fill the impulse lines and/or condensate vessels with an appropriate liquid.