Precautions - Mitsubishi Electric M80V Series Manual

M800V/M80V Series PLC Interface Manual
5 Appx.1: PLC window

5.5 Precautions

5.5 Precautions
Precautions
(1) Set the read window start R register (R424, R428, R432) and the write window start R register (R426, R430, R434),
securing enough space for the number of windows in between. When mistakenly set in the area, it does not read or write
correctly. Up to 16 R registers are needed for one read window or write window. (18 R registers are necessary when the
extended interface is used.)
(Example)In case the reading starts at R8300 and the number of read windows is set to 10, it uses 160 registers in total.
Therefore, the writing start R register must be set in R8460 or later.
(2) Area of read/write window must be within the user area.
When reading/writing is attempted exceeding the user area, reading/writing finishes on the right spot.
Set the reading/writing start R registers and the numbers of read/write windows properly to ensure that all the R registers
to be used fit within the user area.
(3) With this function, up to 100 windows can be read or written. Scan time in ladder may be extended, depending on the
number of read/write windows.
(4) When 4 consecutive data are first read and then 3 consecutive data are read using the same window, the forth data will
not be set to "0", leaving the first data read.
(5) When read control signal and write control signal are ON at the PLC stop, reading and writing are conducted because this
function operates even while PLC is stopped.
(6) Read/write window area 1, 2, or 3 can be specified in an arbitrary order, as long as they are specified within R register
user area.
(7) Using this function, do not create PLC in which parameters are written each time scan is performed. It might affect some
performance. It might also affect the measurement tool such as NC Analyzer2. If parameters are written consecutively on
the PLC, the operation alarm (M50 5003) occurs.
(8) When the parameter "#1251 set23/bit5" is set to "1", the operation alarm (M50 5003) display can be released. However,
use this as a temporary setting until the user PLC is corrected because the operation may become unstable.
(9) If you create such a PLC program that write servo or spindle parameter per scan, the operation error (M01 0292) will
occur upon the execution of the following functions:
 Spindle/C axis changeover
 Speed monitor mode signal ON
 High-speed synchronous tapping
 PLC axis indexing
However, when the parameter "#1282 ext18/bit7" has been set to "1", the writing of the servo parameter or spindle
parameter stops temporarily to execute the functions above so that this error does not occur.
(10) The range of value to write/read is within the setting range of the R register.
However, the value to write/read for the PLC window may be limited according to the combination of the control units and
the PLC setting units.
(Example) When the value of the data converted from the PLC setting units to the control unit exceeds the maximum
command value of the NC.
(11) When data is read from a diameter specification axis (an axis where "#1019 dia" is set to "1"), the data is converted to a
radius value, and then output to the read window. When data is written to the diameter specification axis, data input in the
write window is handled as a radius value, and the data is converted to a diameter value before written. To input/output
the diameter value on the PLC window, set the parameter "#1752 cfgPR02/bit0" (PLC window diameter specification
valid) to "1".
711 IB-1501616-D