What is the best test to determine if a small resistance (2 ohms or less) is affecting a high current circuit?

The voltage drop test is particularly effective in assessing whether a small resistance is influencing the operation of a high current circuit. This test measures the difference in voltage across a component or section of the circuit while it is in operation. If a small resistance is present, it will create a measurable voltage drop when current flows through it, indicating that the resistance is having an effect on the circuit.

In high current scenarios, even a small resistance can have significant implications for the overall performance of the system, potentially leading to increased heat generation and loss of efficiency. By measuring the voltage drop, technicians can discern if the resistance is within acceptable limits or whether it may be contributing to unwanted effects, allowing them to diagnose issues such as poor connections or corrosion that can lead to larger problems in high power applications.

Other methods, such as current measurement or resistance checks, do not directly indicate the impact of the resistance on circuit performance under load conditions. Continuity tests are useful for ensuring connections are intact, but they do not assess the effect of resistance in a live circuit scenario. Therefore, implementing a voltage drop test is the best method to evaluate the influence of small resistances in high current circuits.