9 - 17
MELSEC-Q
9 MAJOR POSITIONING CONTROL
Restrictions
(1) A 1.8ms error will occur in the current value update timing when the stored
"current feed value" is used in the control.
A 56.8ms error will occur in the current value update timing when the stored
"machine feed value" is used in the control.
(2) The "current feed value" and "machine feed value" may differ from the values
set in "
Da.6
Positioning address/movement amount" of the positioning data if
the movement amount per pulse is not set to "1".
Monitoring the current value
The "current feed value" and "machine feed value" are stored in the following
buffer memory addresses, and can be read using a "DFRO (P) command" from
the PLC CPU.
Buffer memory addresses
Axis 1 Axis 2 Axis 3 Axis 4
Md.20
Current feed value
800, 801 900, 900 1000, 1001 1100, 1101
Md.21
Machine feed value
802, 803 902, 903 1002, 1003 1102, 1103
Example
Program in which the axis 1 current feed value is read to D104 and D105
<Read current feed value to D104 and D105>