4
Product Description
EDBC250SIO | 2.0
25
4.6
Safety-related Input Ratings
4.6.1
Safety-related Ratings of a Single-channel Application
The table below lists the safety-related ratings of a single-channel safety function that uses
one input of the safe I/O module. All components involved in the safety function must be
taken into account in order to assess whether the desired safety level is achieved.
Safety-related ratings of a single-channel application
Highest safety integrity level to EN 62061:2010
SIL2
Highest safety integrity level to EN 61508:2010
SIL2
Highest performance level to EN ISO 13849-1:2015
Cat. 2 / PL d
Hardware fault tolerance (HFT) in single-channel
application
(IEC 61508:2010/EN ISO 13849-1:2015)
0
(a fault of the application may cause the safeguard to fail)
Safety-related ratings
Ambient temperature, 25 °C
Ambient temperature, 55 °C
Probability of failure on demand (PFD
avg
),
proof test interval: 10 years,
(IEC 61508:2010) for one input (up to fieldbus)
5.40 * 10
-6
(0.06% of entire
PFD
avg
of 10
-2
at SIL2)
2.23 * 10
-5
(0.23% of entire
PFD
avg
of 10
-2
at SIL2)
Probability of failure per hour (PFH),
proof test interval: 10 years,
(IEC 61508:2010) for one input (up to fieldbus)
1.24 * 10
-10
1/h
(0.02% of entire
PFH of 10
-6
at SIL2)
5.27 * 10
-10
1/h
(0.05% of entire
PFH of 10 -6 at SIL2)
Probability of failure on demand (PFD
avg
),
proof test interval: 20 years,
(IEC 61508:2010) for one input (up to fieldbus)
1.10 * 10
-5
(0.11% of entire
PFD
avg
of 10
-2
at SIL2)
4.77 * 10
-5
(0.48% of entire
PFD
avg
of 10
-2
at SIL2)
Probability of failure per hour (PFH),
proof test interval: 20 years,
(IEC 61508:2010) for one input (up to fieldbus)
1.28 * 10
-10
1/h
(0.02% of entire
PFH of 10
-6
at SIL2)
5.79 * 10
-10
1/h
(0.06% of entire
PFH of 10
-6
at SIL2)
Diagnostic coverage (DC)
to EN ISO 13849-1:2015
98.32%
95.89%
Safe failure fraction (SFF)
99.27%
98.51%
Mean time to dangerous failure (MTTF d) to EN ISO
13849-1:2015
100 years
(calculated: 283 years)
100 years
(calculated: 185 years)
