Endress+Hauser Proline Promag H 500, Руководство по эксплуатации

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Proline Promag H 500 PROFIBUS DP Installation
Hauser 29
4. Reinstall the sensor in the pipe, and in doing so make sure that the seal is clean and
in the right position.
‣
If thin-walled pipes carrying food are welded correctly:
Disassemble the sensor and seal even if the seal is not damaged by the heat when
mounted.
It must be possible to open the pipe by at least 8 mm (0.31 in) to permit disassembly.
Mounting the seals
Comply with the following instructions when installing seals:
1. In the case of metal process connections, the screws must be tightened securely. The
process connection forms a metal connection with the sensor, which ensures a
defined compression of the seal.
2. In the case of plastic process connections, observe the maximum torques for
lubricated threads: 7 Nm (5.2 lbf ft); always insert a seal between the connection and
the counterflange in the case of plastic flanges.
3. Depending on the application the seals should be replaced periodically, particularly if
gasket seals are used (aseptic version)! The interval between changes depends on the
frequency of the cleaning cycles, the cleaning temperature and the medium
temperature. Replacement seals can be ordered as an accessory →  232.
Mounting grounding rings (DN 2 to 25 (1/12 to 1"))
Pay attention to the information on potential equalization .
In the case of plastic process connections (e.g. flange connections or adhesive fittings),
additional ground rings must be used to ensure potential matching between the sensor
and the medium. If grounding rings are not installed, this can affect the measuring
accuracy or cause the destruction of the sensor as a result of the electrochemical
decomposition of the electrodes.
• Depending on the option ordered, plastic disks are used instead of grounding rings
on some process connections. These plastic disks only act as "spacers" and do not
have any potential matching function. Furthermore, they also perform a significant
sealing function at the sensor/process connection interface. Therefore, in the case
of process connections without metal grounding rings, these plastic disks/seals
should never be removed and should always be installed!
• Grounding rings can be ordered separately as an accessory from Hauser
→  232. When ordering make sure that the grounding rings are compatible with
the material used for the electrodes, as otherwise there is the danger that the
electrodes could be destroyed by electrochemical corrosion!
Material specifications →  224.
• Grounding rings, including seals, are mounted inside the process connections.
Therefore the installation length is not affected.