Precautions - Yamaha RCX222 User Manual

3. Precautions

1. When using a dual-lead proximity sensor as an input signal, check whether or not it
is within input signal specifications.
If the sensor has a high residual voltage during on and off, this might cause
malfunctions.
2. Take noise preventive measures when using an inductive load such as a solenoid
valve as an output load. For example, connect a diode (high-speed type) in parallel
at both ends of a load, as a surge killer to protect against noise.
3. If a short occurs in the load or an excessive current flows, the internal over-
current protective circuit shuts off the interface circuit. Once this protective circuit
is activated, it is not possible to restore the previous state. In some cases, heat
generated inside might damage the internal circuits, so always draw current only
within the rated load.
4. As a noise prevention, keep the machine power cables separate and make sure
wires are well shielded.
5. Do not keep supplying the external 24V DC power to the I/O power connector
while controller power is off. The controller might malfunction if the external 24V is
continuously supplied.
3. Precautions
Chapter
5
5-23