Endress+Hauser Proline Promag H 500, Руководство по эксплуатации

Страница: 54 / 240

Electrical connection Proline Promag H 500 PROFIBUS DP
54 Hauser
7.4.2 Connection example, standard scenario
Metal process connections
Potential equalization is generally via the metal process connections that are in contact
with the medium and mounted directly on the sensor. Therefore there is generally no need
for additional potential equalization measures.
7.4.3 Connection example in special situations
Plastic process connections
In the case of plastic process connections, additional grounding rings or process
connections with an integrated grounding electrode must be used to ensure potential
matching between the sensor and the fluid. If there is no potential matching, this can
affect the measuring accuracy or cause the destruction of the sensor as a result of the
electrochemical decomposition of the electrodes.
Note the following when using grounding rings:
• 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/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 . 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!
• Grounding rings, including seals, are mounted inside the process connections. Therefore
the installation length is not affected.
Potential equalization via additional grounding ring
1
3 2
4
2
A0028971
1 Hexagonal-headed bolts of process connection
2 O-ring seals
3 Plastic disk (spacer) or grounding ring
4 Sensor