Application Precautions - Omron CPM1A Operation Manual

Application Precautions

Caution
!
5

Application Precautions

WARNING
!
Caution
!
xviii
• Locations subject to static electricity or other forms of noise.
• Locations subject to strong electromagnetic fields.
• Locations subject to possible exposure to radioactivity.
• Locations close to power supplies.
The operating environment of the PC System can have a large effect on the lon-
gevity and reliability of the system. Improper operating environments can lead to
malfunction, failure, and other unforeseeable problems with the PC System. Be
sure that the operating environment is within the specified conditions at installa-
tion and remains within the specified conditions during the life of the system.
Observe the following precautions when using the PC System.
Always heed these precautions. Failure to abide by the following precautions
could lead to serious or possibly fatal injury.
• Always connect to a ground of 100 Ω or less when installing the Units. Not con-
necting to a ground of 100 Ω or less may result in electric shock.
• Always turn off the power supply to the PC before attempting any of the follow-
ing. Not turning off the power supply may result in malfunction or electric
shock.
• Mounting or dismounting I/O Units, CPU Units, or any other Units.
• Assembling the Units.
• Connecting or wiring the cables.
• Connecting or disconnecting the connectors.
Failure to abide by the following precautions could lead to faulty operation of the
PC or the system, or could damage the PC or PC Units. Always heed these pre-
cautions.
• Fail-safe measures must be taken by the customer to ensure safety in the
event of incorrect, missing, or abnormal signals caused by broken signal lines,
momentary power interruptions, or other causes.
• Construct a control circuit so that power supply for the I/O circuits does not
come ON before power supply for the Unit. If power supply for the I/O circuits
comes ON before power supply for the Unit, normal operation may be tempo-
rarily interrupted.
• If the operating mode is changed from RUN or MONITOR mode to PROGRAM
mode, with the IOM Hold Bit ON, the output will hold the most recent status. In
such a case, ensure that the external load does not exceed specifications. (If
operation is stopped because of an operation error (including FALS instruc-
tions), the values in the internal memory of the CPU Unit will be saved, but the
outputs will all turn OFF.)
• Always use the power supply voltage specified in the operation manuals. An
incorrect voltage may result in malfunction or burning.
• Take appropriate measures to ensure that the specified power with the rated
voltage and frequency is supplied. Be particularly careful in places where the
power supply is unstable. An incorrect power supply may result in malfunction.
• Install external breakers and take other safety measures against short-circuit-
ing in external wiring. Insufficient safety measures against short-circuiting may
result in burning.
5