Endress+Hauser Proline Promag H 200, Краткое руководство по эксплуатации

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Proline Promag H 200 Electrical connection
Hauser 29
7.2.2 Ensuring potential equalization
!
CAUTION
Electrode damage can result in the complete failure of the device!
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Make sure that the fluid and sensor have the same electrical potential.
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Pay attention to internal grounding concepts in the company.
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Pay attention to the pipe material or grounding.
Connection examples for standard situations
Metal process connections
Potential matching usually takes place via the metallic process connections in contact with
medium which are directly mounted on the measuring transmitter. This usually means that
additional potential matching measures are unnecessary.
Connection example in special situations
Plastic process connections
If the process connections are made of a synthetic material, additional ground rings or process
connections with an integrated ground electrode must be used to ensure the potential between
the sensor and fluid is matched. No potential matching can affect the accuracy of the
measurements or cause the destruction of the sensor through the electrochemical decomposition
of the electrodes.
When using ground rings, note the following points:
• Depending on the option ordered, plastic disks may be installed at the process connections
instead of ground rings. These plastic disks serve only as spacers and have no potential
matching function. In addition, they provide a sealing function at the sensor/process
connection interface. For this reason, with process connections without metal ground rings,
these plastic disks/seals must not be removed, or must always be installed.
• Ground rings can be ordered separately from Hauser as accessories. When placing
the order, make certain that the ground rings are compatible with the material used for the
electrodes. Otherwise, there is a risk that the electrodes may be destroyed by electrochemical
corrosion!
• Ground rings, including the seals, are mounted within the process connections. Therefore,
the fitting length is not affected.