5. Commissioning, operation
Protect the diaphragm monitoring system from heat sources (e.g. pipes or tanks). Do
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not expose the instruments to direct solar irradiation while in operation!
Protected against soot, vapour, dust, corrosive gases, coarse dirt and wide
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fluctuations in ambient temperature. Consider possible restrictions on the ambient
temperature range caused by mating connector used.
5.2.2
Installation
The installation of the diaphragm monitoring system must be carried out in accordance
with the specifications of the respective process connection. Other installation types, e.g.
direct welding, are not permissible and are considered as improper use.
Remove the protective cap not until shortly before installation
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Avoid any contact with or mechanical loading of the diaphragm. Scratches on the
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diaphragm (e.g. from sharp-edged objects) are the main causes of corrosion.
Sealing of the process connection
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- Select suitable sealing for the respective application and diaphragm seal version.
- Centre sealing on the sealing face.
- The diaphragm movement must not be limited due to the sealing.
- When using soft or PTFE sealings, observe the instructions of the sealing manufac-
turer, particularly with regard to tightening torque and load cycles.
For installation, the appropriate fastenings must be used. Mount these with the
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prescribed tightening torque.
5.3 Mounting instructions for diaphragm seal systems with EHEDG and 3-A
Observe the following instructions, especially for EHEDG-certified and 3-A-compliant
instruments.
To maintain the EHEDG certification, one of the EHEDG-recommended process
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connections must be used. These are marked with the logo in the data sheet.
To maintain the conformity to the 3-A standard, a 3-A-compliant process connection
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must be used. These are marked with the logo in the data sheet.
Mount the diaphragm seal system with minimal dead space and able to be cleaned
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easily.
The mounting position of the diaphragm seal system, welding socket and
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instrumentation T-piece should be designed to be self-draining.
The mounting position must not form a draining point or cause a basin to be formed.
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With the process connection via an instrumentation T-piece, the branch L of the
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T-piece must not be longer than the diameter D of the T-piece (L ≤ D).
WIKA operating instructions, model DMSU21A
EN
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