Wiring For Control Circuit Terminals - Omron MX2 Series User Manual

2 Design
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Wiring for Control Circuit Terminals

Wiring for Control Circuit Terminals

• Although two terminals L are internally connected, the terminal CM2 is a common terminal for input
and analog signals and mutually isolated from them.
Do not short-circuit or ground these common terminals.
In addition, do not ground these common terminals via external equipment.
When finished wiring, check the external equipment ground conditions.
• For wiring to the control circuit terminals, use twisted-pair shielded cables (recommended diameter:
2
0.75 mm ). Connect the sheathed shielded cable to each common terminal. The cable length should
be 20 m or shorter.
• Twist a cable connected to the terminal TH (thermistor input) with a cable of the terminal L individu-
ally, and separate them from other L common cables. Since the current flowing through the therm-
istor is weak, separate the thermistor cable from main circuit cable (power cable). The thermistor
connection cable should be 20 m or shorter.
• To use a relay for a multi-function output terminal, connect a surge-absorbing diode in parallel with
the coil.
• The control circuit terminal block has two rows of terminals. Start wiring from the lower terminals. Wir-
ing from the upper terminals makes it difficult to wire the lower terminals.
Precautions for Correct Use
• Wiring the I/O signal lines for more than one inverter results in creating a sneak path in the
circuit. Connect a diode for sneak current prevention. For wiring instructions, refer to
Precaution for Wiring Control Circuit Terminals on page 2-41.
• The control circuit connection cables should be 20 m or shorter.
• Separate the cables for control circuit terminal connection from the main circuit cable (power
cables) and the relay control circuit cable. If you cannot avoid crossing two types of cables,
keep them at right angles to each other. Not doing so may result in the inverter malfunction.
Separate signal lines from power supply lines when wiring.
• Do not short-circuit the terminals H and L of the analog power supply, and the terminals P24
and L of the power supply for input signal. Doing so may result in failure of the inverter.
• After wiring, lightly pull the wire to confirm that it is connected properly.
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Multi-function Compact Inverter 3G3MX2-EV2 User's Manual (I666-E1)