Onicon F-3500 - Installing Grounding Rings

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F-3500 Insertion Electromagnetic Flow Meter Manual 02/18 - 0665-11 Page 15
3.2.6 Installing Grounding Rings
* Additional straight run may be required upstream of the upstream grounding ring based
on the nature of the upstream obstruction. Refer to the chart in Section 3.1 on page 11 of this
manual to determine how much straight run is required.
Grounding rings are used to suppress electrical interference at the installation location for
electromagnetic ow meters. They are provided in pairs and are installed upstream and downstream
of the ow meter. The use of grounding rings signicantly reduces electrical noise and may be
necessary for proper operation of ow meters installed in lined or non-conductive pipes.
Installation Instructions
1. Install the rings upstream and downstream of the meter as shown above.
(Please note that the straight run requirements shown above are only for locating the
grounding rings with respect to the F-3500 ow meter. The complete straight run
requirements for this meter are found in Section 3.1 on page 11 of this manual.)
2. Install each grounding ring sandwiched between (2) ANSI Class 150 anges and (2)
gaskets.
3. Center each gasket on the grounding ring surface. Do not allow the gasket to protrude
into the ow stream.
4. Use the torque specications provided with the gaskets when tightening the ange
bolts.
5. Wire the two grounding rings together as shown and connect them to the ow meter
earth wire. Connect this to a known good earth connection. See Section 3.2.5 on
page 21 of this manual for additional information on identifying an acceptable earth
connection.
Typical Installation In Non-conductive Pipe
5 DIA
10 DIA
Gaskets (4 pl)
Grounding Rings (2pl)
*