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Entry type: FAQ, Entry ID: 109743141, Entry date: 03/09/2017

Safety-relevant characteristics of 3SU1200-1SK10-2SA0 sensor switch

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This entry contains information on the safety-related characteristics of a 3SU1 sensor switch.


Is there a B10 or B10d value for this sensor switch?


There is no B10 or B10d value for the 3SU1200-1SK10-2SA0 sensor switch.
B10 or B10d values are only available for electromechanical switching devices.
As the sensor switch is purely an electronic component, no such values are available.

However, the following safety-relevant characteristic values are available and can be used to establish the SIL or PL level.

MTBF: 535.6 years (4,691,620 h)
MTTF: 535.6 years (4,691,620 h)
MTTFd: 1071.2 years
Worst case MTTFd: 107.12 years
FIT: 213
B10d: - (only available for electromechanical switching devices)

Calculation formula:

MTBF = 1 / Lambda = MTTF (basic formula from IEC 62061)
MTTFd = MTTF x 2 (in accordance with DIN EN ISO 13849-1 Annex C)
Worst case MTTFd = (MTTF x 2) / 10

The safety-relevant MTTFd and FIT values are given on the product data sheet.

The calculated values apply under the following conditions:
Stationary operation in a maintained environment (Ground Benign)
Tu: 40 °C average ambient temperature for components
Zf: Continuous operation; 8760 h per annum
FIT: 1 FIT = 1 failure per 10e9 component hours
λ: Failure rate in 1 / time unit
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