| Effects of Redundancy on
Reliability |
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| u | Active
Redundancy: Both components operate all the |
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| time but
only one is needed. |
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| u | Failure
occurs only when both fail or (EP1)*(EP2) |
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| u | Thus reliability is:RS = 1 - P(1-RI) |
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| Example:
Use two components and both |
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| components
have a reliability of 0.90. |
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| In a
series| Rs = .9*.9 = .81 |
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| (above) |
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| Redundant| Rs = 1-(1-.9)2 =
.99 |
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| Two
redundant components in a series| |
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| Rs = .99*.99 = .98 |
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