Endress+Hauser Proline Promag 55S, Техническая информация

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Proline Promag 55S
Hauser 11
Plastic pipes and isolating lined pipes
Normally, potential is matched using the reference electrodes in the measuring tube. However, in exceptional
cases it is possible that, due to the grounding plan of a system, matching currents flow over the reference elec-
trodes. This can lead to destruction of the sensor, e.g. through electro-chemical decomposition of the electro-
des. In such cases, e.g. for fiberglass or PVC pipings, it is therefore
essential that you use additional ground
disks for potential equalization. This applies also to two-phase or two-component flow, where the fluid is not
well mixed or its constituents are not mixable.
"
Caution!
• Risk of damage by electrochemical corrosion. Note the electrochemical insulation rating, if the ground disks
and measuring electrodes are made of different materials.
• Also, observe company-internal grounding guidelines.
A0004377
Potential equalization/ground disks in the case of plastic pipes or isolating lined pipes
(ground cable: copper wire at least 6 mm
2
/ 10 AWG)
Plastic pipes and isolating lined pipes
In such cases, install the measuring instrument without potential in the piping:
• When installing the measuring device, make sure that there is an electrical connection between the two
piping runs (copper wire, at least 6 mm
2
/ 10 AWG).
• When using ground disks in plastic or isolating lined pipes, ensure that they are electrically connected with
each other (copper wire at least 6 mm
2
/ 10 AWG).
• Make sure that the mounting material used does not establish a conductive connection between the pipe
and the measuring device and that the mounting material withstands the torques applied when the threaded
fasteners are tightened during installation.
• Check the galvanic isolation using an insulation tester (protection against contact).
• Also comply with the regulations applicable to potential-free installation.
!
Note!
For the remote version, both the sensor and the transmitter must be installed so that they are potential-free.
A0004378
Potential equalization and cathodic protection (connecting cable: copper wire at least 6 mm
2
/ 10 AWG)
1 Isolation transformer power supply
2 Electrically insulated
1
2 2