Yokogawa ADMAG AXF - Manual (Page 49)

IM 01E20D01-01E 4-15
4. WIRING
The electromotive force of the magnetic flowmeter is
minute and it is easy to be affected by noise. And also
that reference electric potential is the same as the
measuring fluid potential. Therefore, the reference
electric potential (terminal potential) of the flowtube
and the converter also need to be the same as the
measuring fluid. Moreover, that the potential must be
the same with ground. The magnetic flowmeter is
equipped with an grounding ring that makes a connec-
tion with the charge of the measured fluid for ground-
ing and protects the lining.
Be sure to ground according to Figure 4.2.19.
• Class D requirements (ground resistance.
100 ⍀ or less).
• TIIS Flameproof type: Class C requirements
(ground resistance, 10 ⍀ or less) or Class A
requirements (ground resistance, 10 ⍀ or less)
• Explosion proof type except TIIS: Domestic
electrical requirements as regulated in each
country.
Grounding ring
600 V vinyl insulated
electric cable
(2 mm
2 or larger)
F0430.EPS
In case grounding rings
are used. In case grounding rings are
not used.
(Available only for metal piping)
Figure 4.2.19 Protective Grounding Terminal Location
(8) Installing the Cover (Size 2.5 to 1000 mm
(0.1 to 40 in.))
Install the cover to the flowtube by turning it in the
direction of the arrow as shown below. Tighten the
cover locking screw counterclockwise using a hexago-
nal wrench (nominal size 3) to lock the cover.
F0431.EPS
Figure 4.2.20 Installing the Terminal Box Cover (Remote
Flowtube)