Protection Criterion | Target Structure P/S Calculation |
.85 On (default) | –0.850 V |
.85 IRF | –0.850 – | Structure P/S – Structure IRF | Example: –0.850 – | –1.200 – –0.800 | = –1.250 Note: The value in the field User IR Correction (if any) is used instead of the | Structure P/S – Structure IRF | equation. |
100 mV | Native P/S – 0.100 – | Structure P/S – Structure IRF | Example: –0.550 – 0.100 – | –1.200 – –0.800 | = –1.050 Note: The fields Native P/S and Native Date can be included with any survey regardless of how old. PCS Axis always finds the most recent native reading and date, and the most recent pair of structure “on/off” readings (Structure P/S and Structure IRF). This means if the current-year survey includes only “on” readings, PCS Axis uses the last “on/off” reading and native date. This is the case until a new “on/off” reading is taken. |
300 mV | This is no longer recognized by NACE RP0169 or DOT regulations. |
Ref Read | Add the field Test Point Reference P/S in the grid when using “Ref Read” (reference reading) protection criterion. |
Ag/AgCl | Functions the same as “.85 On” but uses –0.800V instead. Use this protection criterion for off-shore (saltwater) or tank “on” readings when using silver/silver chloride half cell. |
The field Target Structure IRF is used for a facility to meet criteria and the calculated minimum value for the Structure IRF field. | |
.85 On criteria | Calculation: Target Structure IRF = Null |
.85 IRF (off) and 100mV criteria | Structure IRF can be compared to Target Structure IRF to determine if the inspection is in compliance. If Structure IRF is more negative than Target Structure IRF, the test point is in compliance. • Calculation for .85 IRF Criteria: Target Structure IRF = -.85. Target Structure P/S is calculated for an inspection that has a Structure IRF. • Calculation for 100mV Criteria: Target Structure IRF = Native P/S - 0.1. Native Date must be added in the grid. Target Structure IRF is calculated for an inspection that has a Structure IRF. Native P/S = Most recent Native P/S before the date of the Structure P/S and Structure IRF. |
.85 On | Calculation: Target Structure IRF = Null |
300 mV | Calculation: Target Structure IRF = Null |
Ref Read | Calculation: Structure P/S = Null |