Position units

Position conversions can be calculated in two phases:

1. Computing the feedback resolution.
2. Applying the conversion factors of the desired units.

Computing feedback resolution

Position

The position resolution depends directly on the feedback used and is based on EMCL units (c). EMCL supports as position feedbacks:

• Digital encoder
• Digital halls
• Analog halls
• Analog input
• SinCos
• PWM encoder
• Resolver

Digital Encoder

The resolution of the tachometer is computed as follow:

Digital halls

Analog halls

Analog Halls constant value is always 4096.

Analog input

Analog Input constant value is always 4096.

SinCos

SinCos constant value is always 1024.

PWM encoder

PWM encoder constant is always 65535

Resolver

Resolver constant is always 65535.

SSI

Applying the conversion factors of the desired units

A direct conversion factor can be applied to obtain the desired units after the computation of the resolution. The next sections shows the conversions of the most typical units.

Position

c

rev

rad

º

mm

For linear Voice coils the pole pitch variable is equal to the stroke (SubIndex 0x05). Otherwise, the pole pitch value is the pole pitch (SubIndex 0x03)

um

For linear Voice coils the pole pitch variable is equal to the stroke (SubIndex 0x05). Otherwise, the pole pitch value is the pole pitch (SubIndex 0x03)

Related registers

0x608F - Position encoder resolution

0x2301 - Motor pair poles

0x2701 - Motor parameters