Measuring Input Terminals - Omega RD2800 Series User Manual

4. CONNECTIONS
1

Measuring input terminals

Make sure to turn off the power supply to prevent
an electric shock.
(1) Measuring input terminals are located on the
down left of the terminal board.
(2) For the connections to the input terminals, use
cables terminated by crimp style terminals with
insulation sleeves.
Caution
Allowable input voltage
Input type
±10 VDC
Voltage,
Thermocouple input
±60 VDC
Resistance
thermometer input
2 Connections of DC voltage (current) input
Use twisted cables for instrumentation as the
input cables for the purpose of suppressing noise.
For current inputs, mount shunt resistors
(Section 16.2) to the channels to be measured
before connections.
(+)
(-)
Twisted cable for
instrumentation
DC voltage input
cover
Terminal
Warning
A high voltage may be applied to the measuring input terminals due to common mode noise. The
allowable noise value is 30 VAC or less, or 60 VDC or less. Make sure that the noise is lower than the
allowable value. Mount the terminal cover after connections for the purpose of preventing an electric
shock and to protect the input wires. In the case of thermocouple input, the mounting of the terminal cover
can reduce the reference junction compensation error.
4.4 Measuring Input Terminals
Allowable input voltage
(range: ±2V or less)
(range: ±5V or more)
±6 VDC
1 2 3 4
mark of measuring input terminals
－１６－
3 Connections of thermocouple inputs
Make sure to use thermocouple wires (or
extension wires) to the input terminals of your
recorder. If a copper wire is used halfway, a
noticeable measuring error occurs. Don't use a
pair of thermocouple wires in parallel with other
instruments (controller,
malfunction may occur.
Red (+)
White (-)
Extension wire
Thermocouple
4 Connections of resistance thermometer inputs
Use a 3-core cable where each lead wire has an
equal resistance value. Don't use one resistance
thermometer in parallel with other instruments
(controller, etc.).
3-core cable
A
(Same diameter,
same length)
B
B
Resistance thermometer
etc.), otherwise a
1 2 3 4
1 2 3 4
Note: Use a 3-core cable where
each lead wire has an equal
diameter and an equal resistance