9
DANGER
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When controlling a running C Controller module (data
modification) by connecting a personal computer to the C
Controller module, create an interlock circuit on user
programs so that the whole system functions safely all the
time.
This must be also done when performing any other controls
(e.g. operating status change (status control)) or
operations instructed from the computer.
In these controls, especially the one performed from an
external device to a C Controller module in a remote
location, some C Controller side problem may not be
resolved immediately due to failure of data
communications.
To prevent this, create an interlock circuit on user
programs and establish corrective procedures for
communication failure between the external device and the
C Controller module.
CAUTION
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Do not install the control wires or communication cables
together with the main circuit or power wires, or bring them
close to each other.
Keep a distance of 100 mm (3.94 inch) or more between
them.
Not doing so could result in malfunctions due to noise.
z
When controlling a lamp, heater or solenoid valve using an
output module, large current (approximately ten times
greater than in normal conditions) may flow when the
output is turned ON from OFF.
Take preventive measures such as replacing the module
with the one having sufficient rated current.
When the C Controller system is powered ON-OFF, the control output may not be
supplied normally for a little while because of the delay time and rise time
difference between the C Controller system power supply and the external power
supply for the control target (especially in DC).
In the case of a DC output module, for example, when power is applied to the
external power supply first and then the C Controller system power supply, the
DC output module may temporarily generate false output at power-on of the C
Controller system. Therefore, it is necessary to configure a circuit in which power
is applied to the C Controller system first.
Also, erroneous operations may be performed when the external power supply or
C Controller module is faulty.
To prevent the erroneous operations from resulting in entire system failure, and
from a viewpoint of fail-safe system operation, configure circuits outside the C
Controller module for the areas that will lead to mechanical damage and/or
accidents due to erroneous operations (emergency stop circuit, protective circuit,
interlock circuit, etc.)
A system design circuit example based on the above viewpoint is shown on the
next page.
Summary of Contents for Q06CCPU-V-H01
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