🔍 Key Concepts

• Input impedance and how it affects how much current flows through the tester and you • Why a tester’s voltage rating must relate properly to the maximum expected system voltage • Relationship between current, voltage, and shock hazard (Ohm’s Law)

💭 Think About

• Ask yourself: does a higher input impedance mean more or less current has to flow through the meter (and potentially through you) for it to work? • Consider what might happen if you connect a tester that is rated for a lower voltage than the circuit you’re measuring. • For each option, imagine you’re measuring the highest voltage you expect on the vessel: which combination best limits current and is still safely rated for that voltage?

✅ Before You Answer

• Verify which choices use high input impedance versus low input impedance, and decide which better limits current flow. • Check which options have a voltage rating at or above the maximum expected voltage, and which do not. • Eliminate any options that either allow too much current to flow or have a voltage rating below what you might actually encounter.