Cathodic Protection Tester Practice Exam

When using an analog meter, to obtain an upscale reading, which terminal should the reference electrode be connected to?

1. Negative terminal

2. Ground terminal

3. Positive terminal

4. Neutral terminal

The correct answer is: Positive terminal

To obtain an upscale reading when using an analog meter, the reference electrode should be connected to the positive terminal. In a cathodic protection system, the positive terminal is generally associated with the area being measured, allowing the meter to register a voltage level properly. An upscale reading indicates that the potential of the structure being protected is more negative compared to the reference electrode, which is essential for determining the adequacy of the cathodic protection. Connecting the reference electrode to the positive terminal ensures that the voltage generated by the difference in electrical potential is correctly interpreted by the meter. This is critical because the functionality of an analog meter relies on the flow of current from positive to negative, and connecting to the positive terminal helps facilitate this process in the context of measuring corrosion potential.