Classification of safety functions depending on the encoder type

Depending on the deployed encoder, the safety functions can reach different safety classifications.

Safety functions

STO

1)

SS1

SS2

SOS

SLS

SSR

SDI

SLI

 SMS  

Encoder type

Safety Integrity Levels(SIL)3)/

Performance Level (PL)2)

Note

I

(incremental sine encoder
with zero pulse)

SIL3/

PLe

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL3/

PLe

-

E, F

(EnDat 2.1 with sine/cosine traces)

SIL3/

PLe

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL3/

PLe

Only the sine/cosine traces are evaluated.

S, T, U, V

Hiperface

SIL3/

PLe

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

Only the sine/cosine traces are evaluated.

P, Q

(EnDat 2.2 light)
digital and
sine/cosine traces

SIL3/

PLe

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL2/

PLd

SIL3/

PLe

 Sine/cosine traces in the encoder required

P, Q

(EnDat 2.2 light)
digital

-

-

-

-

-

-

-

-

-

 no sine/cosine traces present

1)

The encoder type is not relevant for STO
2)

according to EN ISO 13849-1
3) according to EN/IEC 62061

 

NOTICE

 

SIL3 and PLe can at STO only be achieved if

  • in the safe sine encoder monitoring (SEM) Prm9 + Prm10 ≤ 24 h