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[Design Precautions]
WARNING
Configure safety circuits external to the product to ensure that the entire system operates safely even when
a fault occurs in the external power supply or the product. Failure to do so may result in an accident due to
an incorrect output or malfunction.
(1) Configure external safety circuits, such as an emergency stop circuit, protection circuit, and
protective interlock circuit for forward/reverse operation or upper/lower limit positioning.
(2) Outputs may remain on or off due to a failure of an output circuit relay or transistor, triac.
Configure an external circuit for monitoring output signals that could cause a serious accident.
In an output circuit, when a load current exceeding the rated current or an overcurrent caused by a load
short-circuit flows for a long time, it may cause smoke and fire. To prevent this, configure an external safety
circuit, such as a fuse.
Configure a circuit to turn on the programmable controller and then the external power supply.
If the external power supply is turned on first, an accident may occur due to an incorrect output or
malfunction.
[Design Precautions]
CAUTION
Do not bundle the control lines or communication cables together with the main circuit lines or power
cables. Keep a distance of 100mm (3.94 inches) or more between them. Failure to do so may result in a
malfunction due to noise.
When a device such as a lamp, heater, or solenoid valve is controlled through an output module, a large
current (approximately ten times greater than normal) may flow when the output is turned from off to on.
Take measures such as replacing the module with one having a sufficient current rating.
