Cathodic Protection Tester Practice Exam

To measure the amount and direction of current in a pipeline, which equipment would you typically use?

1. Voltmeter

2. Ammeter

3. Galvanometer

4. Oscilloscope

The correct answer is: Ammeter

To measure the amount and direction of current in a pipeline, the most appropriate equipment to use is an ammeter. An ammeter is designed specifically for measuring electric current in a circuit, providing readings in amperes. This is essential in cathodic protection systems because understanding the current flow is crucial for determining the efficiency and effectiveness of the protection measures in place. When connected in series with the circuit, the ammeter allows you to not only quantify the amount of current but also infer the direction of current flow by observing the polarity of the connections. This is particularly valuable in pipeline applications, where current may be influenced by external factors like soil resistivity and coating integrity. Other instruments, such as a voltmeter, are intended for measuring voltage and would not provide the desired current measurements. A galvanometer, while capable of detecting current, is typically used for small currents and may not be as precise for larger currents expected in a pipeline context. An oscilloscope measures voltage signals over time and is more suited for analyzing waveforms rather than directly measuring current in a static pipeline scenario. Therefore, an ammeter is the go-to choice for accurately assessing current in this application.