Glossary
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© 2010 Wieland Electric GmbH | BA000256 | 12/2012 (Rev. I)
Characteristic safety values
In the following, you will find the results of calculations of the MTTFd, PFD and PFH values
of different system configurations. They apply under following conditions:
Units are permanently in operation:
24 h per day, 365 days per year
Service life (PFH – applications):
20 years
Proof test interval (PFD – applications):
1 year
Average ambient temperature:
40°C
Calculation variants
Base module
E
A
Variant 1:
1. single-channel input - single-channel output
2. single-channel input - dual-channel output
3. dual-channel input - single-channel output
4. dual-channel input - dual-channel output
Base module
E
A
Input
expansion
Base module
E
A
Base module
E
A
Relay output
Relay output
expansion
expansion
Input
expansion
Variant 2:
1. single-channel input - single-channel output
2. single-channel input - dual-channel output
3. dual-channel input - single-channel output
4. dual-channel input - dual-channel output
Variant 3:
1. single-channel input - single-channel output
2. single-channel input - dual-channel output
3. dual-channel input - single-channel output
4. dual-channel input - dual-channel output
Variant 4:
1. single-channel input - single-channel output
2. single-channel input - dual-channel output
3. dual-channel input - single-channel output
4. dual-channel input - dual-channel output
Содержание samos
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