SEW-Eurodrive CMP40 - 112, Руководство по эксплуатации

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3 Functional safety (FS)
Achievable safety integrity
Addendum to the Operating Instructions – Synchronous Servomotors CMP40 – 112, CMPZ71 – 100
16
3.8 Achievable safety integrity
A safety-rated encoder complements a safety system consisting of several system
components.
The safety-rated encoders AK0H and AK1H are certified for the safety functions men-
tioned above according to the following standards:
• SIL 2 according to EN 62061/IEC 61508
• PL d according to EN ISO 13849-1
The achieve safety integrity in the entire safety system, performance level (PL) or
safety integrity level (SIL) is determined by the following:
• The selected safety structure, category (Cat.)
• Reliability of the used system components (PL, B
10d
, MTTF
d
, ...)
The MTTF
d
value is calculated specifically for the application based on the B
10d
value for the component and the switching frequency of the application.
• Diagnostic coverage (DC
avg
)
The diagnostic coverage is realized via an external encoder evaluation unit. The
external encoder evaluation unit must meet the requirements in chapter "Encoder
evaluation unit" (→
2
26).
• Failure due to a common cause (CCF) with categories 2, 3, and 4.
The achieved safety integrity for the selected safety system must be determined in the
overall evaluation of the system. The required characteristic safety values and safety
characteristics for the safety-rated encoders in chapter "Technical data" (→
2 24)
must be observed.
In addition to the product documentations, the characteristic safety values of compon-
ents by SEW‑EURODRIVE are also available on the SEW‑EURODRIVE homepage
on the Internet and in the SEW‑EURODRIVE library for the Sistema software of the In-
stitute for Occupational Safety and Health of the German Social Accident Insurance
(IFA, formerly BGIA).
3.9 Encoder evaluation
Adhere to the permitted encoder temperature, see chapter "Encoder" (→
2
24). If op-
eration within the specified limits cannot be guarantee, cyclical monitoring of the en-
coder status is mandatory, for example via the parameter channel of the encoder in-
terface. Respective measures must be taken if necessary.
If a safety-rated encoder AK0H, AK1H is used in safety technology, a encoder evalu-
ation unit is additionally required to diagnose the encoder (monitoring). The encoder
evaluation unit must meet the specifications in chapter "Encoder evaluation
unit" (→
2
26).
When safety-rated encoders AK0H and AK1H are operated in combination with safety
modules from SEW‑EURODRIVE, for example MOVISAFE
®
UCS..B or DCS..B, the
requirements to the encoder monitoring are met.
22491465/EN – 03/2016