Actual Position

Type:	Axis Status Register
RMC70 Address:	Fn:8, where n = 8 + the axis number
RMC150 Address:	Fn:8, where n = 8 + the axis number
System Tag:	_Axis[n].ActPos, where n is the axis number
How to Find:	Axes Status Registers Pane, Basic tab
Data Type:	REAL
Units:	pu

Description

The Actual Position is the measured position of the axis at any moment, updated every control loop. This status register is valid only on position control axes. The Actual Position is calculated from the transducer as follows:

Linear MDT, SSI or Resolver Input:

Actual Position = (Counts x Position Scale) + Position Offset

Rotary SSI or Resolver Input:

See the Rotary Scaling topic for details.

Quadrature Input:

Actual Position = (Counts x Position Scale)

Voltage Input:

Actual Position = (Voltage x Position Scale) + Position Offset

Current Input:

Actual Position = (Current x Position Scale) + Position Offset

To properly scale the counts to position-units, see the Position Scale topic.

If the Actual Position is noisy, it can be filtered. See the Actual Position Filter topic for details.

24-Bit Limit

The Actual Position is calculated from the Counts register. For SSI and quadrature inputs, this value may exceed 24 bits. See the Exceeding 24 Bits section of the Feedback Resolution topic for details on the 24-bit limitation of the Counts register.