3.6. Wiring of Measurement Input Terminals
(1) Allowable input voltage
•
Thermocouple input (burnout disabled), DC voltage input (±2 V max.): ± 10 Vdc max.
•
DC voltage input (±5 to ±50 V): ±60 V max.
•
Thermocouple input (burnout enabled), resistance thermometer (RTD) input: ±6 Vdc max.
Handling Precautions
•Use crimp terminals with insulating sleeves on the end of wires connected to the input terminals.
(2) DC voltage (or current) input
For input, use twisted cable made for instrumentation
use, in order to suppress noise. For current input,
connect a shunt resistor between the current input
terminals of that channel before wiring.
(3) Thermocouple (TC) input
Be sure to use thermocouple wire (or compensating leads)
to the input terminals of this recorder. If copper wire is
used part of the way, a significant measuring error will
occur. Avoid connecting a pair of thermocouple wires to
another device (controller, etc.) in parallel because such a
connection may affect the measurement of each device. If a
parallel connection is unavoidable, check whether the
effects are within the allowable range under the following
conditions:
•Set the burnout to disabled.
•Ground the device that you wish to connect in parallel at one point. In addition, install the device near the ARF200 and if possible
use the same power supply.
•Do not shut off the power of either device during operation.
(4) Resistance thermometer (RTD) input
Use a 3-core cable in which each lead has equal resistance.
Also, do not connect a single RTD in parallel with more
than one recorder (controller, etc.).
Handling Precautions
・
The allowable amount of noise on the measurement input terminals is 30 Vac (or 60 Vdc) or less.
Because of common mode noise and the like, take care that the allowable noise level is not exceeded.
After wiring, attach the terminal cover to prevent electric shock and protect the input wires. Also, the
terminal cover can reduce the reference junction compensation error for thermocouple input.
・
Channels are isolated from each other. Note, however, that the C terminals for RTDs are
short-circuited on the ARF _ _ _ AS (100 ms input cycle models) between channels 1 & 4, 5 & 8, and 9
1 2 3 4 5 6
Red (
+
)
DC voltage
input
1 2
3 4 5
6
White (
-
)
Twisted cable
for
instrumentation
(-)
(+)
Compensating
wire
Thermocouple
3-core cable, each wire having the
same diameter, same length, and
same resistance (each less than
10
Ω
).
Resistance thermometer
A
B
C
1 2 3 4 5 6
10