Emerson 0471-0128-02 Profile units, 10 0x608F Positionencoderresolution, 11 0x6091 Gearratio

7.3.9Profile units

The implementation provides a means to convert profile units into position controller and drive units. All scaling values are standard profile objects. The following objects are supported:

Table 7.22 Supported profile units

Index	Name
0x608F	position_encoder_resolution
0x6091	gear_ratio
0x6092	feed_constant

For positions, the scaling control includes a feed constant, a gear ratio and an encoder revolution. These values are combined by the implementation into a simple scaling numerator and denominator. It is possible to change these values non-cyclically (i.e. using SDOs), in which case the scaling numerator and denominator and any position limit values are recalculated in the background. It is not, however, possible to change these values cyclically (i.e. by mapping PDOs to them).

For velocities, in addition to the position constants described above. These values are combined into a simple numerator and denominator to scale velocities to internal velocity units. This scaling also properly handles remainders (i.e. when used on a reference or feedback, accumulate the remainder and add it to subsequent velocity values, and when used with a limit, round up or down). It is possible to change these values non-cyclically (i.e. using SDOs), in which case the scaling numerator and denominator is recalculated in the background. It is also necessary to re-scale velocity limit values with the new factor. It is not possible to change these values cyclically (i.e. by mapping PDOs to them).

7.3.100x608F Position_encoder_resolution

This read only object indicates the configured encoder increments per number of motor revolutions. The information is read from the drive's encoder configuration.

Table 7.23 Position_encoder_resolution

0x608F	Position_encoder_resolution
Sub-index 0
Access: RO		Range: N/A	Size: Unsigned 8	Unit: N/A
Default:	2
Description:
Sub-index 1
Access: RO		Range: 0 to 0xFFFFFFFF	Size: Unsigned 32	Unit: N/A
Default:	1
Description:	Encoder increments
Sub-index 2
Access: RO		Range: 0 to 0xFFFFFFFF	Size: Unsigned 32	Unit: N/A
Default:	1
Description:	Motor revolutions

7.3.110x6091 Gear_ratio

This object is used to apply scaling. When configured, appropriate user units can be used to control the position of the shaft beyond a gearbox. The gear ratio is calculated using the following formula:

gear ratio = motor shaft revolutions / driving shaft revolutions

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