Wiring – Yokogawa Touch Screen GP20 User Manual
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IM 04L51B01-02EN
Installation and Wiring
Wiring
• To prevent electric shock while wiring,
make sure that the power supply is
turned off.
• If a voltage of more than 30 VAC or
60 VDC is to be applied to the output
terminals, use ring-tongue crimp-on
lugs with insulation sleeves on all
terminals to prevent the signal cables
from slipping out when the screws be-
come loose. Furthermore, use double-
insulated cables (dielectric strength
of 2300 VAC or more) for the signal
cables on which a voltage of 30 VAC
or 60 VDC or more is to be applied.
For all other signal cables, use basic
insulated cables (dielectric strength of
1390 VAC). To prevent electric shock,
attach the terminal cover after wiring
and make sure not to touch the termi-
nals.
• Applying a strong tension to the input
and output signal cables connected to
the GX/GP may damage the cables or
the GX/GP terminals. To avoid apply-
ing tension directly to the terminals,
fix all cables to the rear of the mount-
ing panel.
• To prevent fire, use signal cables with
a temperature rating of 70°C or more.
• Do not apply voltages that exceed the
following values to the input termi-
nals. Doing so may damage the GX/
GP.
GX90XA
• Maximum input voltage: ±60 VDC
• Maximum common mode voltage: ±60
VDC (under measurement category II
conditions)
GX90XD
• Maximum input voltage: +10 VDC
• Maximum common mode voltage: ±50
VDC
The GX/GP is an installation category II
product.
Precautions to Be Taken While Wiring
Take the following precautions when wiring the input signal
cables.
• With a screw terminal, we recommend that you use a
crimp-on lug with an insulation sleeve (M4 for power
supply wiring, M3 for signal wiring).
Crimp-on lug with an insulation sleeve
Recommended signal
wiring crimp-on lug
N1.25-MS3
(JST Mfg. Co., Ltd.)
• With a clamp terminal, we recommend the following
wire.
GX90XA
Cross-sectional area
0.05 mm
2
to 1.5 mm
2
(AWG30 to 16)
Stripped wire length
5 to 6 mm
GX90XD
Cross-sectional area
0.2 mm
2
to 1.5 mm
2
(AWG24 to 16)
Stripped wire length
9 to 10 mm
RS-422/485 (/C3 option)
Cross-sectional area
0.08 mm
2
to 1.5 mm
2
(AWG28 to 16)
Stripped wire length
6 to 7 mm
FAIL output/status output (/FL option)
Cross-sectional area
0.33 mm
2
to 2.0 mm
2
(AWG22 to 14)
Stripped wire length
10 to 11 mm
• Take measures to prevent noise from entering the
measurement circuit.
• Move the measurement circuit away from the power
cable (power circuit) and ground circuit.
• Ideally, the object being measured should not
generate noise. However, if this is unavoidable,
isolate the measurement circuit from the object.
Also, ground the object being measured.
• Shielded wires should be used to minimize the noise
caused by electrostatic induction. Connect the shield
to the ground terminal of the GX/GP as necessary
(make sure you are not grounding at two points).
• To minimize noise caused by electromagnetic
induction, twist the measurement circuit wires at
short, equal intervals.
• Make sure to earth ground the protective ground
terminal through minimum resistance (less than 100 Ω).
• When using internal reference junction compensation
on the thermocouple input, take measures to stabilize
the temperature at the input terminal.
• Always use the terminal cover.
• Do not use thick wires which may cause large heat
dissipation (we recommend a cross sectional area of
0.5 mm
2
or less).
• Make sure that the ambient temperature remains
reasonably stable. Large temperature fluctuations
can occur if a nearby fan turns on or off.
• Connecting the input wires in parallel with other
devices can cause signal degradation, affecting all
connected devices. If you need to make a parallel
connection, then
• Turn the burnout detection function off.
• Ground the instruments to the same point.
• Do not turn ON or OFF another instrument during
operation. This can have adverse effects on the
other instruments.
• RTDs cannot be wired in parallel.
Wiring Procedure
A terminal cover is screwed in place on the I/O terminal
block. A label indicating the terminal arrangement is
affixed to the cover.
1. Turn off the GX/GP, and remove the terminal cover.
2. Connect the signal cables to the terminals.
Recommended
torque for
tightening the
screws
Screw terminal
(M3)
0.5 to 0.6 N•m
Clamp terminal
GX90XA: 0.4 N•m
GX90XD: 0.5 N•m
3. Attach the terminal cover and fasten it with screws. The
appropriate tightening torque for the screws is 0.6 N•m.
Note
With a clamp terminal, if you use a single wire whose
diameter is 0.3 mm or less, you may not be able to clamp
the wire securely to the terminal. Take measures to
securely clamp the wire such as by folding the conductor
section that will be connected to the clamp terminal in half.