Yokogawa AXFA14G/C - Manual (Page 13)

IM 01E20C02-01E 4-1
4. WIRING
4. WIRING
This chapter describes the wiring on the converter side
only. For information relating to wiring on the
flowtube side, refer to the user’s manual of the AXF
Remote Flowtube (IM 01E20D01-01E).
WARNING
The wiring of the magnetic flowmeter must be
performed by expert engineer or skilled person-
nel. No operator shall be permitted to perform
procedures relating to wiring.
CAUTION
Once all wiring is complete, check the connec-
tions before applying power to the instrument.
Improper arrangements or wiring may cause a
unit malfunction or damage.
4.1 Wiring Precautions
Be sure to observe the following precautions when
wiring:
CAUTION
• In cases where the ambient temperature
exceeds 50 °C (122°F), use external heat-
resistant wiring with a maximum allowable
temperature of 70
°C (158°F) or above.
• Do not connect cables outdoors in wet weather
in order to prevent damage from condensation
and to protect the insulation.
• Do not splice the cable between the flowtube
terminal and the converter if it is too short.
Replace the short cable with a cable that is the
appropriate length.
• All the cable ends must be provided with round
crimp-on terminals and be securely wired.
• The signal cables must be routed in separate
steel conduit tubes 16 (JIS C 8305) or flexible
conduit tubes 15 (JIS C 8309).
• Always route the power and output signal
cables in separate steel conduit tubes, except
when the power supply voltage is 24 V and
four-core cables are used for wiring. Keep
conduits or flexible tubes watertight using
sealing tape.
• Ground the remote flowtube and the converter
separately.
• Cover each shield of the signal cable with vinyl
tube or vinyl tape to avoid contact between two
shields or between a shield and a case.
• When waterproof glands or union equipped
waterproof glands are used, avoid tightening
the glands with an excessive torque.
• In case of 24V power supply version, it comes
with a plug. Use this plug to cover the unused
wiring port when wiring the instrument with only
one, four-core cable.
• Be sure to turn power off before opening the
cover.
• Before turning the power on, tighten the cover
securely.
• The terminal box cover is locked by the special
screw. In case of opening the terminal box
cover, use the hexagonal wrench attached. For
handling the locking screw, refer to Figure
4.4.1.
• Be sure to lock the cover by the special screw
using the hexagonal wrench attached after
installing the cover. For handling the locking
screw, refer to Figure 4.4.12.
• Explosion protected types must be wired in
accordance with specific requirement (and, in
certain countries, legal regulations) in order to
preserve the effectiveness of their explosion
protected features.
4.2 Cables
(1) Dedicated Signal Cable (AXFC)
Outer jacket 10.5 (0.413")
Tape
Shield (C)
Insulation
Insulation
Shields (SA and SB)
Conductors (A and B)
F0401.EPS
Figure 4.2.1 Dedicated Signal Cable AXFC
The flow signal is transmitted via this dedicated cable.
The cable is constructed with double shielding over the
two conductors, and heat-resistant vinyl is used for the
outer jacket material.