Yokogawa AXFA14G/C - Manual (Page 8)

IM 01E20C02-01E 4-2
4. WIRING
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.
Finished diameter: 10.5 mm (0.413")
Maximum length: 100 m (330 ft)
Maximum temperature: 80
°C (176°F)
IMPORTANT
If the cable is longer than required, cut off any
extra length rather than coiling it up, and termi-
nate the conductors as shown in Figure 4.2.2.
Avoid using junction terminal boards to extend
the cable length, as this will interrupt the shield-
ing.
20 (0.8) ␾ 10.5 (0.4)
AXFC
L (Specified Dimensions)
150
± 5
8 (0.3) max.
150
± 5
70 (2.76)
60 (2.36) 90 (3.54)
(5.9) (5.9)
55 (2.17)
90 (3.54)
50 (1.97)
25 (0.98)
SA SB
A
C
B A
C
B
8(0.3) max.
White Black Red
White Black Red
F0402.EPS
Unit : mm
(approx. inch)
On the
converter
side On the
flowtube
side
Figure 4.2.2 Treatment of Dedicated Signal Cables
CAUTION
• As crimp terminals A, B, SA, SB and C have
their own electrical potentials, securely insulate
them so as not to come in contact with one
another.
• To prevent a shield from coming in contact with
another shield or the case, cover each shield
with a vinyl tube or wrap it in vinyl tape.
NOTE
Conductors A and B carry the signal from the
electrodes, and C is at the potential of the liquid
(signal common). Shields SA and SB are kept
at the same potentials as the individual elec-
trodes (these are actively driven shields.) This is
done to reduce the effect of the distributed
capacitance of the cable at long cable length.
Note that, since the signals from the individual
electrodes are impedance converted inside the
converter, errors will result if they come in
contact with any other component. Great care
must be taken in the cable end treatment.
(2) Excitation Cable/Power Cable/Output
Cable
JIS C3401 control cable equivalent
JIS C3312 power cable equivalent
14 AWG Belden 8720 equivalent
Outer Diameter:
With no gland option;
6.5 to 12 mm (0.26 to 0.47 in.)
With gland options EG, EU and EW;
10.5 or 11.5 mm (0.41 or 0.45 in.)
With gland options EP;
6 to 12 mm (0.24 to 0.47 in.)
Nominal Cross Section:
Single wire; 0.5 to 2.5 mm 2
Stranded wire; 0.5 to 1.5 mm 2
In case of power cable, Green/Yellow covered conduc-
tor shall be used only for connection to PROTECTIVE
CONDUCTOR TERMINALS. Conform to IEC227,
IEC245 or equivalent national authorization.