5 wiring cautions, Wiring cautions -4, Caution – Yokogawa YTA320 User Manual
Page 27
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<5. Wiring>
5-4
IM 01C50B01-01E
5.5 Wiring Cautions
() General-use Type and Intrinsically Safe
Type
Use metal conduit wiring or a waterproof gland
(metal wiring conduit JIS F 8801) for cable wiring.
• Apply nonhardening sealant to the threads of
the wiring tap and a flexible fitting for secure
waterproofing. Figure 5.10 shows an example
of wiring on the output side. This example also
applies to the wiring on the input side.
F0510.ai
Apply a nonhardening
sealant to the threads for
waterproofing.
Wiring conduit
Tee
Flexible fitting
Drain plug
Figure 5.0 Example of Wiring Using a Wiring
Conduit
(2) TIIS Flameproof Type
Wire cables through a flameproof packing adapter,
or using a flameproof metal conduit.
■ Wiring cable through flameproof packing
adapter for only TIIS flameproof type (see
Figure 5.)
• Use only flameproof packing adapters
approved by Yokogawa.
• Apply a nonhardening sealant to the terminal
box connection port and to the threads on the
flameproof packing adapter for waterproofing.
F0511.ai
Flameproof packing adapter
Apply a nonhardening
sealant to the threads for
waterproofing.
Wiring conduit
Tee
Flexible fitting
Drain plug
Figure 5. Typical Cable Wiring Using Flameproof
Packing Adapter
• Measure the cable outer diameter in two
directions to within 0.1mm.
• Calculate the average of the two diameters, and
use packing with an internal diameter nearest to
this value from among the three provided (see
Table 5.1).
Table 5.1
Flameproof Packing and Appropriate
Cable Outer Diameters
Wiring Port
Thread
Diameter
Appropriate
Cable Outer
Diameter
(mm)
Identifying
Mark
Part
Number
G1/2
8 - 10
10.1 - 12
16
16
8 - 10
10 - 12 G9601AM
Follow the procedure below to install the flameproof
packing adapter.
1. Screw the flameproof packing adapter into
the terminal box until the O-ring touches the
terminal box wiring port (at least 6 full turns),
and tighten the lock nut.
2. Insert the cable through the union cover, the
union coupling, the gland the clamp nut, the
clamp ring, one washer, the rubber packing,
and the packing box, in that order.
3. Insert the end of the cable into the terminal box.
4. Tighten the union cover to grip the cable.
When tightening the union cover, tighten
approximately one turn past the point where
the cable will no longer move up and down.
Proper tightening is important. If it is too tight, a
circuit break in the cable may occur; if not tight
enough, the flameproof effectiveness will be
compromised.
CAUTION
Tighten the union cover approximately one turn
after the point where you can no longer shift
the cable up and down by hand. Take great
care in this step, since proper tightening is very
important.
5. Fasten the cable with tightening the clamp nut.
6. Tighten the lock nut on the union cover.
7. Connect the cable wires to each terminal.