SAME SKY | SERIES: AMT33 | DESCRIPTION: MODULAR COMMUTATION ENCODER

date 09/12/2024 | page 3 of 11

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WAVEFORMS

Z

A

B

I

P

T

S S S S

Quadrature signals with index showing

counter-clockwise rotation

Figure 1

Z

U

V

W

I

P

C

T

S S S S S S

Commutation signals with index (The programmable

direction setting dictates in which direction of rotation U

will lead V, and V will lead W)

Figure 2

Parameter

Description

Expression

Units

T

period

360/M

mechanical degrees

P

pulse width

T/2

mechanical degrees

I

index width

360/(PPR*4)

mechanical degrees

S

U/V/W state

width

60

electrical degrees

T/6

mechanical degrees

C

phase

spacing

120

electrical degrees

T/3

mechanical degrees

The following parameters are defined by the resolution and pole count selected for

each encoder, where PPR = resolution and M = motor poles.

Parameter

Description

Expression

Units

Notes

PPR

resolution

Pulses Per Revolution

This is the user selected value and the format

all resolutions are listed in

CPR

counts

PPR x 4

Counts Per Revolution

This is the number of quadrature counts the

encoder has

T

period

360/R

mechanical degrees

P

pulse width

T/2

mechanical degrees

S

A/B state width

T/4

mechanical degrees

This is the width of a quadrature state

I

index width

T/4

mechanical degrees

The width of a once per turn index is the state

width for A & B lines

The following parameters are defined by the resolution selected for each encoder. The

encoders resolution is listed as Pulses Per Revolution (PPR), which is the number of

periods (or high pulses) over the encoders revolution.

Note:

For more information regarding PPR, CPR, or LPR (Lines Per Revolution) view https://www.sameskydevices.com/blog/what-is-encoder-ppr-cpr-and-lpr

Additional Resources: Product Page | 3D Model