11
CJ-series Features Section 1-2
Failure Point Detection:
FPD(269)
Diagnoses a failure in an instruction block by monitoring the time between
execution of FPD(269) and execution of a diagnostic output and finding which
input is preventing an output from being turned ON.
Error Log Functions The error log contains the error code and time of occurrence for the most
recent 20 errors (user-defined or system-generated errors).
Maintenance Functions The CJ-series PLCs record information useful for maintenance, such as the
number of power interruptions and the total PLC ON time.
Other Functions
Data Trace Function The content of the specified word or bit in I/O memory can be stored in trace
memory by one of the following methods: scheduled sampling, cyclic sam-
pling, or sampling at execution of TRSM(045).
Fixed Cycle Time Function A fixed (minimum) cycle time can be set to minimize variations in I/O response
times.
I/O Refreshing Methods I/O refreshing can be performed cyclically and immediately by programming
the immediate-refreshing variation of the instruction.
Peripheral Servicing
Priority Mode
The CPU Unit can be set to execute peripheral servicing periodically and
more than once in each cycle. Up to five items can be set for priority servicing,
including the RS-232C port, peripheral port, CPU Bus Units, and Special I/O
Units. This feature supports applications that require giving priority to servic-
ing peripheral devices over program execution, such as for host monitoring
systems for process control where response speed is important.
PLC Setup Functions PLC operation can be customized with PLC Setup settings, such as the maxi-
mum cycle time setting (watch cycle time) and the instruction error operation
setting, which determines whether instruction processing errors and access
errors are treated as non-fatal or fatal errors.
FPD
Input preventing
diagnostic output
from going ON
Specified address
in I/O memory
Trace memory
The PLC’s initial settings can be
customized with the PLC Setup.
To Next Page
Loading...
Need help?
General
