Measurements Along the Route:
The route is entered (selection of measurement points and the appropriate variables to be measured) in the GASACOR2 application. After the route has been imported to the mobile device, the actual measurements can be taken using the GASACOR2MOBILE application and the MEg20 device. The measurements are automatically assigned to the measurement point. The results of the measurement are exported back into GASACOR2, where they are assessed. For the application to run properly, there needs to be an integrated database in the GASACOR2 application.
Time and Polar Measurements:
These are a special type of measurement. This part of the application is more variable, allowing measurement parameters to be entered. This part of the application can also be used separately.
1.1 Measurement Along the Route
When taking measurements along the route, it is necessary to search for the measurement point at the measurement site. The variables to be measured are predefined for this point. Variables can be measured in pairs, although it is also possible to measure one variable on its own.
Diag.1 . Measurement along the route
Diag.2. Measurement of two voltages when measuring along the route
The operator is informed of the length of the measurement; the measurement may be stopped at any time. The result of the measurement for each variable is its average, minimum, and maximum. These results can also store the measurement length, nominal deviation as well as all samples measured.
Diag. 3. Measurement values.
1.1 Corrosion Survey Measurement
1.1.1 Time Measurement
When taking time measurements, any two variables (voltage and current) are measured on both channels, most often measuring the current into the sample. The input or output current into or out of the pipes is measured using a specific steel sample with a unit area (100cm2) and the potential of the pipes against the probe. The measurement process generally lasts for several hours (24h). The measured potential size and the size and direction of the current into the sample can be used to determine the level of risk to the pipes.
The following parameters can also be entered:
- Soil resistance and probe distance when measuring soil resistance using the Wenner method
- Moisture content of soil
- Area and resistance of sample
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Measurement site
1.1.2 Polar Measurement
When taking polar measurements – measurement of stray currents – 2 direct-current voltages are measured in two directions perpendicular to each other, SpZ and SpJ (joint probe-west, joint probe-south). Three probes are used to take the measurements (Cu/CuSO4 reference electrodes); these are inserted into the ground so that one probe–joint is connected to the MEg 20 as the earth and the other two probes are inserted into the ground perpendicular to each other. The junction of this one probe and the joint probe faces in a north - west direction, and the junction of the second probe is in a north – south direction.
To calculate the density of stray currents, the probes also need to be calibrated. Calibration is performed when the probes are in place (inserted into the ground) next to each other. 75 samples are measured (1min 25s); the first 25 samples are not counted, while the average is calculated from the others. The calibration voltage measured is taken account of in the results of the polar measurement. The following parameters can also be entered:
- Soil resistance and probe distance when measuring soil resistance using the Wenner method
- Moisture content of soil
- Measurement site
- Distance of probes during polar measurement
