ControlLogix MAG Instruction?

Does a MAG instruction in a controlLogix gear the master to the slave with drive resolution counts or to the conversion constant?

i have a MAG with the following parameters ratio of 1, slave count = 1, master count = 1, master reference = actual and ratio format = real

Both drives are rotary with a 10:1 gearbox the master drive has a drive resolution of 8192 and a conversion constant of 81920 and Slave drive also has a drive resolution of 8192 but a conversion constant of 81919

Looking at the actual position of the slave it appears to be advancing past the master actual position slowly over time but the physical master and slave are staying in time on the machine.

There doesn't seam to be any mechanical difference between the 2 drives on the machine so i am assuming the conversion constant of the slave has no effect on the slave position when geared to a master.

Thanks

Mitchell said:

Does a MAG instruction in a controlLogix gear the master to the slave with drive resolution counts or to the conversion constant?

i have a MAG with the following parameters ratio of 1, slave count = 1, master count = 1, master reference = actual and ratio format = real

Click to expand...

Ratio format = Real

• Parameter [Ratio] is in use
• slave position reference {in axis units} = Master Position {in axis units} * [ratio]
• parameter [Master counts] is not used
• parameter [Slave Counts] is not used

Ratio format = integer

• parameter [Master counts] is in use
• parameter [Slave Counts] is in use
• Slave Position {in encoder counts} = Master Position {in encoder counts} / [Master counts] * [Slave Counts]
• Parameter [Ratio] is not used

Internally MAG is using an incremental equation with rollover and carry

See page 128 of the manual
http://literature.rockwellautomation.com/idc/groups/literature/documents/rm/motion-rm002_-en-p.pdf