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<4. WIRING>
4-1
IM 01E25D11-01EN
4. WIRING
4.1 Wiring the Remote Flowtube
This section describes the wiring of the remote
flowtube only. For information relating to the wiring
of the converter, refer to the user’s manual of the
AXFA11 Magnetic Flowmeter Remote Converter
(IM 01E20C01-01E).
WARNING
The wiring of the magnetic flowmeter must
be performed by expert engineer or skilled
personnel. No operator shall be permitted to
perform procedures relating to wiring.
CAUTION
Once all wiring is complete, check the
connections before applying power to the
instrument. Improper arrangements or wiring
may cause a unit malfunction or damage.
4.1.1 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,
e.g. inside the terminal box of the flowtube.
• 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).
• 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.
• Be sure to turn the power off before opening
the terminal box cover.
• Before turning the power on, tighten the
terminal box cover securely.
• When opening the terminal box cover, use a
hexagonal wrench (nominal size 3 mm). For
handling the locking screw, refer to Figure
4.1.7.
• Be sure to lock the cover using a hexagonal
wrench (nominal size 3 mm) after installing the
cover. For handling the locking screw, refer to
Figure 4.1.11.
• When submersible type or optional code DHC
is selected, waterproof glands, signal and
excitation cables are attached.
In order to preserve the effectiveness of
waterproof features, the terminal box cover
and waterproof glands must not be detached
from flowmeter.
IMPORTANT
Prepare the signal cable and the excitation cable
almost the same length. It is recommended to lay
them together closely.