Safety encoder: ES7S, EG7S, AS7W, AG7W, AS7Y, AG7Y

Designation

Requirement

Safety requirements

≥ SIL 2

Diagnostic coverage (DC)

≥ 90%

Fault presumptions

According to EN 61800‑5‑2:2017, table D.8

Monitoring of the phasor length "r"

with

a = A – A for cosine signals and

b = B – B for sine signals

Safe state

Phasor length "r" outside of the range

350 mV ≤ r ≤ 700 mV

Terminating resistor between A and A or B and B

120 Ω ±10%

Terminating resistor between A, A, B, B to the supply voltage and reference ground

> 1 kΩ

Sampling frequency

At least twice as high as the frequency maximally occurring in the application at the encoder signal outputs (Nyquist criterion)

If the safety encoders are operated with prefabricated encoder cables from SEW‑EURODRIVE on evaluation electronics from SEW‑EURODRIVE, these previously mentioned requirements have been met.