Mitsubishi Electric MELSEC-Q Series - Page 45

2 REPLACEMENT OF CPU MODULE
2 - 15
: Available : Although available, specifications such as setting method partially differ. : Not available
Function Description
AnS series Q series
Precautions for replacement Reference
AnSHCPU
A2US(H)
CPU(-S1)
A2ASCPU
(-S1/S30)
QnUCPU
Control
Data protection
function (system
protection, keyword
registration/
password
registration)
Prevents unauthorized access
from peripherals to programs
and comments in the built-in
memory of a CPU module,
memory cassettes, or memory
cards.

The Q series prohibits each file
from being read/written by
password registration, whereas
the AnS series prohibit the
parameters and programs from
being read/written to the user
memory by keyword registration.
Section
2.4.2
Output status
setting at changing
from STOP to RUN
The settings for the output
status at changing from STOP
to RUN (Y) between "re-output
operation status before STOP"
and "output after operation
execution".
 
To replace the AnS series,
resetting the parameters is
necessary.
-
Clock function
Reads or writes the internal
clock data of the CPU module.
The clock data consists of year,
month, date, hour, minute,
second and a day of the week.

The Q series handles the year in
four digits (western calendar),
whereas the AnS series handles
the year in the last two digits.
-
Debug
Write during RUN
Changes the programs of
(writes programs to) the
running CPU module.
 
For the Q series, it is necessary
to set the reserved capacity for
the write during RUN in advance.
(default value is 500 steps.)
Section
2.4.3
Status latch
Stores the data of the entire
device memory area at the time
of error occurrence in the built-
in memory or a memory
cassette and monitors the
stored data by a peripheral.
 
The Q series does not support
the status latch function.
-
Sampling trace
Stores the data of the specified
device memory area in the
built-in memory or a memory
cassette at a set interval to
check the changes of the
device memory area and
monitors the stored data by a
peripheral.
 
The Q00UJCPU does not support
the sampling trace function.
-
steps operation
Stops the execution of a
sequence program at the
specified steps.
 
The Q series does not support
the steps operation function.
Consider debugging with the GX
Works2 simulation function.
-
Off-line switch
Separates the device memory
area used for the OUT
instruction from the operation
processing of sequence
program.
 
The Q series does not support
the off-line switch function.
Consider using the forced on/off
function for external I/O.
-
Maintenance
Online I/O module
change
Replaces input/output modules
while the CPU module is in
operation.
 
To replace the input/output
modules online, use the Process
CPU.
-
Self-diagnostic
function
Performs self-diagnostics to
check for errors, detect errors,
and stop the CPU module.
 
Error codes differ between the
AnS series and Q series.
-