What Is the Best Tool for Testing AC Current?
If you're trying to measure alternating current (AC) in your home or project setup, it's important to choose the right tool—not just for accuracy, but for safety.
While the Fluke 101 multimeter is a fantastic device for many everyday electrical tasks, it does not support AC current (ampere) measurement. In this article, we’ll explore:
- What AC is
- Why the Fluke 101 isn’t suitable for AC current testing
- What tools are best for the job
- Safe practices for checking AC-related values
What Is AC?
Alternating current (AC) is the type of electricity found in most households and buildings.
Unlike direct current (DC), where electrons flow in one direction, AC constantly reverses direction—like the tide of the sea.
It’s what powers your:
- Wall outlets
- Large appliances
- Lighting systems
AC is measured in volts (V) and amperes (A), with amperes indicating the amount of current flowing through a circuit.
❌ Can You Use the Fluke 101 to Measure AC Current?
No.
The Fluke 101 multimeter supports:
- AC Voltage (up to 600V)
- DC Voltage
- Resistance
- Continuity
- Diode and basic capacitance checks
But it does NOT measure:
- AC current (A~)
- DC current
- Milliamps or microamps
There is no ampere input terminal, and no amp mode on the selector dial.
The Best Tools for Measuring AC Current
1. Clamp Meter (Most Recommended)
A clamp meter is the safest and easiest way to measure AC current. Just:
- Clamp it around a single live wire
- Set it to AC current (A~)
- Read the value instantly—no need to disconnect anything
Popular models:
📌 Important: Clamping around both the live and neutral wires will cancel the current reading—always clamp one wire only.
2. Plug-in Energy Monitor
If you want to measure the current drawn by a home appliance, a plug-in energy monitor is perfect:
- Plug it into the wall
- Plug your appliance into the monitor
- It shows voltage, current, wattage, energy usage safely and conveniently
3. Multimeters That Support AC Current
If you’re experienced and need a multimeter with current-measuring capabilities, look for models like:
These multimeters have a dedicated ampere terminal (10A or mA) and fuse protection—but using them requires proper setup and safety precautions.
Takeways
| AC Measurement Task | Best Tool |
|---|---|
| AC Voltage (outlets, etc.) | Fluke 101 or similar multimeter |
| AC Current (through wires) | Clamp Meter |
| AC Current (appliance load) | Plug-in energy monitor |
| In-circuit diagnostics | Advanced multimeter (e.g. Fluke 117) |
Stay safe, test smart, and use the right tool for the job.
Browse our shop for trusted multimeters, clamp meters, and accessories that help you get the job done safely and accurately.
