What specific type of current does the galvanic isolator test entail using a variable power supply?

The test for a galvanic isolator specifically utilizes direct current (DC) because the operation of the galvanic isolator is primarily concerned with the prevention of galvanic corrosion, which occurs when two dissimilar metals are connected in an electrolyte, such as water. The isolator works by allowing AC power to pass while effectively blocking DC currents that could lead to the corrosion process.

Using a variable power supply for testing allows the assessment of the isolator's effectiveness in blocking DC current while still permitting normal AC operation, simulating conditions that can lead to potential problems on boats. This is critical because the primary goal of a galvanic isolator is to mitigate the risks posed by unwanted DC currents, which can originate from different sources such as electrical systems, shore power connections, and conductive paths through water.

Other types of currents, like AC or RMS (Root Mean Square) currents, while related to the overall electrical environment of Marine applications, do not reflect the specific target of the galvanic isolator test, which is to ensure that DC current is blocked effectively while allowing safe operational AC current to flow.