© exida.com GmbH phoenix contact 06-06-05 r004 v2r0.doc, January 18, 2008
Philipp Neumeier Page 3 of
3
Results for solenoid drivers PI-EX-SD-**-** with Motherboard:
The following table shows how the above stated requirements are fulfilled.
Table 2: Summary for PI-EX-SD-**-** with Motherboard – IEC 61508 failure rates
2
λ
λλ
λ
SAFE
λ
λλ
λ
DANGEROUS
SFF PFD
AVG
284 FIT 0 FIT
3
100% 0,00E+00
Results for top hat rail type solenoid drivers MACX MCR-EX-SL-SD-**-**-LP and
MACX MCR-EX-SL-SD-**-**-LP-SP:
The following table shows how the above stated requirements are fulfilled.
Table 3: Summary for MACX MCR-EX-SL-SD-**-**-LP / MACX MCR-EX-SL-SD-**-**-LP-SP
– IEC 61508 failure rates
2
λ
λλ
λ
SAFE
λ
λλ
λ
DANGEROUS
SFF PFD
AVG
282FIT 0 FIT
3
100% 0,00E+00
The above results show that the solenoid drivers PI-EX-SD-**-** with Motherboard and MACX
MCR-EX-SL-SD-**-**-LP and MACX MCR-EX-SL-SD-**-**-LP-SP - both when loop powered -
can be used for all safety applications.
The calculations are based on the assumption that the devices are mounted in an environment
that is IP 54 compliant (e.g. housing, control cabinet or control room).
The failure rates are valid for the useful life of the solenoid drivers PI-EX-SD-**-** and MACX
MCR-EX-SL-SD-**-**-LP and MACX MCR-EX-SL-SD-**-**-LP-SP (see Appendix 1).
2
It is assumed that practical fault insertion tests can demonstrate the correctness of the failure effects assumed
during the FMEDAs.
3
In order to deal with the excluded faults in the quantitative analysis it might be reasonable to consider a dangerous
failure rate of 0.1 FIT, leading to a SFF of 99,97% and a PFD
AVG
of 4,38E-06 for a proof time of 10 years.
