To properly use a clamp-on-type ammeter for...

🔍 Key Concepts

• How a clamp-on ammeter (also called a clamp meter) measures current using the magnetic field around a conductor • The effect of measuring one conductor vs. multiple conductors in the same circuit on the reading • Why the position of the jaws (open or closed) matters for an accurate magnetic field measurement

💭 Think About

• Think about whether the meter is sensing current directly in the wire or the magnetic field around the wire. What does that imply about how many conductors should be inside the clamp? • If equal currents flow in opposite directions through two conductors inside the clamp, what happens to their magnetic fields? Do they add or cancel? • For the instrument to sense the magnetic field properly, what must be true about the path of the magnetic circuit in the clamp (i.e., the condition of the jaws)?

✅ Before You Answer

• Verify whether a clamp meter is designed to go around a single conductor or around an entire cable with multiple current-carrying conductors. • Confirm what happens to the reading if you place both the outgoing and return conductors inside the clamp together. • Check the manufacturer’s basic operating instruction: should the clamp jaws be fully closed or partially open when taking a reading?

To properly use a clamp-on-type ammeter for measuring current accurately, what must be done?

Enclose multiple conductors within the jaws AND make sure the jaws are closed.

Enclose one conductor within the jaws AND make sure the jaws are closed.

Enclose multiple conductors within the jaws AND make sure the jaws are open.

Enclose one conductor within the jaws AND make sure the jaws are open.

🔍 Key Concepts

💭 Think About

✅ Before You Answer