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MELSEC-Q
 
5   DATA USED FOR POSITIONING CONTROL 
 
5.1.8 Types and roles of monitor data 
The monitor data area in the buffer memory stores data relating to the operating state 
of the positioning system, which are monitored as required while the positioning 
system is operating. 
The following data are available for monitoring. 
 
•
 System monitoring: 
 
Monitoring of the QD75 configuration and operation history (through the system 
monitor data
Md.1
through
Md.19
) 
 
•
 Axis operation monitoring: 
 
Monitoring of the current position and speed, and other data related to the 
movements of axes (through the axis monitor data
Md.20
through
Md.47
) 
 
 The axis monitor data are refreshed every 3.5 ms. Note that "
Md.21
Machine 
feed value" and "
 
Md.22
 
 Feedrate" are refreshed every 56.8ms. Also, 
"
Md.23
Valid M code", is updated when the "M code ON signal [X4, X5, X6, X7]" 
turns ON. 
 
[1]   Monitoring the system 
 
 Monitoring the positioning system operation history 
 
Monitoring details  Corresponding item 
Whether the system is in the test mode or not 
Md.1
 
In test mode flag 
Start information 
Md.3
 
Start information 
Start No. 
Md.4
 
Start No. 
Hour 
Md.5
 
Start    Hour 
Start 
Minute:second 
Md.6
 
Start    Minute:second 
Error upon starting 
Md.7
 
Error judgment 
History of data that 
started an operation 
Latest pointer No. 
Md.8
 
Start history pointer 
Axis in which the error occurred 
Md.9
 
Axis in which the error occurred 
Axis error No. 
Md.10
 
Axis error No. 
Hour 
Md.11
 
Axis error occurrence    Hour 
Axis error occurrence 
Minute:second 
Md.12
 
Axis error occurrence    Minute:second 
History of all errors 
Latest pointer No. 
Md.13
 
Error history pointer 
Axis in which the warning occurred 
Md.14
 
Axis in which the warning occurred 
Axis warning No. 
Md.15
 
Axis warning No. 
Hour 
Md.16
 
Axis warning occurrence    Hour 
Axis warning 
occurrence 
Minute:second 
Md.17
 
Axis warning occurrence    Minute:second 
History of all warnings 
Latest pointer No. 
Md.18
 
Warning history pointer 
Number of write accesses 
to the flash ROM after the 
power is switched ON 
Number of write accesses to flash ROM 
Md.19
 
Number of write accesses to flash ROM