Hello,

before starting gearing command, check whether the sensor is enabled.

<TO>.StatusWord.X0

Then it is possible to read the actual position of the external encoder (that is master) and just use this position as 'mastersyncposition' and in the same cycle set a rising edge to the 'execute' input of the function. You can call it in post servotask or OB1.

Chapter 9.1

https://support.industry.siemens.com/cs/ww/en/view/109766464

Hello David,

I guess you want to synchronize immediately. But as you want to specify a sync position, this is not possible (otherwise you could use MC_GearIn).

Please note that the current technological actual value of the axis is determined in the IPO (see FAQ https://support.industry.siemens.com/cs/ww/en/view/109779884).

When an MC-GearInPos is placed, the actual value is thus from the previous IPO cycle.

I would recommend to calculate a synchronous position (MasterSyncPosition and SlaveSyncPosition) from the actual value of the axis and use synchronization in advance with dynamic parameters. Maybe you can work with high dynamic parameters.

Instead of OB MC-PostServo, the OB MC-PreInterpolator is more suitable. If the sync position is far enough away, MC_GearInPos can also be called in OB1.

Best regards

Manfred