analysis done for double, neeed stats next
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@ -648,7 +648,7 @@ $$ NoOfTestCasesToCheck = \frac{6!}{1!(6-1)!} + \frac{6!}{2!(6-2)!} - \Big( \fra
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$$ NoOfTestCasesToCheck = 6 + 15 - ( 1 + 1 + 1 ) = 18 $$
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As the test case are all different and are of the correct cardinalities (6 single faults and (15-3) double)
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we can be confident that we have looked at all combinations up to two, of the possible faults
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we can be confident that we have looked at all `double combinations', of the possible faults
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in the pt100 circuit. The next task is to investigate
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these test cases in more detail to prove the failure mode hypothese set out in table \ref{tab:ptfmea2}.
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@ -656,7 +656,7 @@ these test cases in more detail to prove the failure mode hypothese set out in t
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\subsection{Proof of Double Faults Hypothese }
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\subsubsection{ TC 7 : Voltages $R_1$ OPEN $R_2$ OPEN }
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\label{pt100:bothfloating}
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This double fault mode produces an interesting symptom.
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Both sense lines are floating.
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We cannot know what the {\adctw} readings on them will be.
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@ -702,5 +702,50 @@ Both values will be out of range.
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\subsubsection{ TC 13 : Voltages $R_1$ SHORT $R_3$ OPEN }
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This shorts the sense+ to Vcc and the sense- to ground.
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Both values will be out of range.
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\subsubsection{ TC 14 : Voltages $R_1$ SHORT $R_3$ SHORT }
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This shorts the sense+ and sense- to Vcc.
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Both values will be out of range.
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\subsubsection{ TC 15 : Voltages $R_2$ OPEN $R_3$ OPEN }
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This shorts the sense+ to Vcc and causes sense- to float.
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The sense+ value will be out of range.
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\subsubsection{ TC 16 : Voltages $R_2$ OPEN $R_3$ SHORT }
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This shorts the sense+ and sense- to Vcc.
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Both values will be out of range.
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\subsubsection{ TC 17 : Voltages $R_2$ SHORT $R_3$ OPEN }
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This shorts the sense- to Ground.
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The sense- value will be out of range.
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\subsubsection{ TC 18 : Voltages $R_2$ SHORT $R_3$ SHORT }
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This shorts the sense+ and sense- to Vcc.
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Both values will be out of range.
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\vspace{20pt}
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typeset in {\Huge \LaTeX} \today
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