Yokogawa µR20000 - Manual (Page 15)

15
IM 04P02B01-02E
Input Signal Wiring
WARNING
• To prevent electric shock while wiring, ensure that the power supply source is
turned OFF.
CAUTION
• The input terminals of this instrument are specific to this instrument. Do
not connect the input terminals of the µR1000, µR1800 or other models, as
malfunction may result.
• If a strong tension is applied to the cable wired to the recorder, the terminals of
the recorder and/or the cable can be damaged. In order to prevent tension from
being applied directly on the terminals, fasten all wiring cables to the rear of the
mounting panel.
• Do not apply a voltage exceeding the following value to the input terminals as
this may damage the recorder.
• Maximum input voltage
Voltage range less than or equal to 200 mVDC, TC, RTD, and DI: ±10 VDC
Ranges other than those listed above: ±60 VDC
• Maximum common-mode voltage
±60 VDC (under measurement category II conditions)
• The recorder is an INSTALLATION CATEGORY II product.
Precautions to Be Taken While Wiring
Take the following precautions when wring the input signal cables.
It is recommended that crimp-on lug with insulation sleeves (designed for 4-mm
screws) be used when connecting the input/output signal wires to the terminals.
However, this does not apply clamped terminals (/H2).
Crimp-on lug with insulation sleeves (for 4-mm screws)
For clamped terminals (/H2), the following wire is recommended.
• Conductive cross-sectional area for single wire: 0.14 mm 2 to 1.5 mm 2 , stranded wire:
0.14 mm 2 to 1.0 mm 2
• Length of the stripped section of the wire: Approx. 5 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.
• It is desirable that the object being measured does 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 noise caused by electrostatic induction.
Connect the shield to the ground terminal of the recorder 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 (cross sectional area of
0.5 mm 2 or less recommended).
• 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.
Installing/Wiring the Recorder