Xylem Magflux Electromagnetic Flow Meter - Manual (Page 116)

116 EN 3.05 MagFlux Manual 1212
Electromagnetic Flow Meter
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Question:
The tubes are made of plastic. Do I need grounding rings?
Answer:
It is a very good question, but there isn't a straight forward answer. It
depends on the sensor type, the size and several other parameters.
The issue is that the liquid and the sensor must have the same voltage
potential.
MJK flow meters with DN ≤ 50 must always be equipped with ground-
ing rings. MJK flow meters with DN > 50 have a built-in ground elec-
trode that makes grounding rings superfluous.
Coated metal tubes always require grounding rings.
If the conductivity is less than 100 µS/cm, grounding rings are recom-
mended.
When in doubt, always contact your local MJK representative or the
MJK hot lines and describe your installation.
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Question:
Are the relays potential-free?
Answer:
Yes, they are.
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Question:
Does the sensor/flow meter comply with IP68?
Answer:
It will once you employ a wall mounting kit, a special cable and a gel
potting kit to protect the electrical connections.
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Question:
Can I use a MagFlux flow meter to measure non-conductive liq-
uids such as diesel oil?
Answer:
No. The electromagnetic principle presupposes conductivity.
The con-
ductivity limit is 5 µS/cm.
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