Mitsubishi Electric MELSEC-Q00U(J)CPU User Manual page 346

● When changing device points, the following refresh ranges must not exceed the corresponding device ranges.
• Refresh range of network module
• Refresh range of CC-Link IE Field Network Basic
• Auto refresh range of intelligent function module
If device points are set exceeding the corresponding device range, data may be written to any other device or an error
may occur.
● The total number of points for the internal relay, latch relay, annunciator, edge relay, link relay, link special relay, step
relay, timer, retentive timer, and counter must be set within the following range.
• Serial number (first five digits) of the Universal model QCPU is "10041" or earlier: Up to 64K points
• Serial number (first five digits) of the Universal model QCPU is "10042" or later: Not limited
● If the device points of the internal user devices are changed and the parameters are written from the "Write to PLC"
screen, the device address may be shifted and does not correspond to the original stored value. Because the shifted
value might be used for the operation, the following files, which are created by using the parameters before the device
point change, cannot be used under existing condition.
• Sequence program files
• SFC program files
• Structured text program files
When change the device points of the internal user devices, perform the following operations from a programming tool.
[Before changing the device points of the internal user devices]
Read devices to be used and each program from the CPU module.
[After the device points of the internal user devices are changed]
Write the devices and each program, which were read before the device point change, to the CPU module.
For the read/write of devices and programs, refer to the following.
Operating manual for the programming tool used
(2) Memory size
Set the internal user devices so that the following condition is satisfied.
(Bit device size) + (Timer, retentive timer, and counter sizes) + (Word device size)
device points
(a) Bit device
For bit devices, 16 points are calculated as one word.
(b) Timer (T), retentive timer (ST), and counter (C)
For the timer (T), retentive timer (ST), and counter (C), 16 points are calculated as 18 words.
(c) Word device
For the data register (D), link register (W), and link special register (SW), 16 points are calculated as 16 words.
344
(X+Y+M+L+B+F+SB+V+S)
(Bit device size) =
(Timer, retentive timer, or counter size) =
(Word device size) =
words
16
(T+ST+C)
18 words
16
(D+W+SW)
16 words
16
 Total number of internal user