Clamps measure current. Probes measure voltage. Having a hinged jaw integrated into an electrical meter allows technicians to clamp the jaws around a wire, cable and other conductor at any point in an electrical system, then measure current in that circuit without disconnecting/deenergizing it.
Clamp meter resources and solutions
Learn how to use clamp meters to quickly troubleshoot some of the most common problems in HVAC and electrical installations, and how to stay out of the blast zone when reading measurements. Get the most out of your clamp meter and know when it’s best to use a clamp meter vs. a digital multimeter.
Helpful resources
Recent stories
Guide to clamp meter symbols, buttons, display and dial functions.
A digital multimeter is essentially a voltage-measuring tool with some current abilities. A clamp meter is basically a current-measuring tool with some voltage abilities. They are distinctly different instruments, each with its own advantages.
Fluke engineers its clamp meters to withstand a high degree of unconventional use—as a wedge, makeshift pliers, nutcracker, whatever a tech might dream up in a moment of need.
Types of clamp meters
Safety is always a priority when working with electricity in industrial sites.
Hall Effect clamp meters can measure both ac and dc current up to the kilohertz (1000 Hz) range- Fluke’s assortment of clamp meters has been engineered to address a wide variety of needs, from routine tasks to specialty projects.
An interior view of a Fluke 325 clamp meter
Clamp meters with flexible coil probes can fit into tight spaces
Fluke’s assortment of clamp meters has been engineered to address a wide variety of needs, from routine tasks to specialty projects.
Measuring ac current with a clamp meter’s jaws. Note: Current flowing in opposite directions cancels each other. If current is moving in opposite directions, place just one conductor within the clamp during measurement.
Knowing the value of inrush current helps technicians locate startup problems
Using Fluke’s 376 True RMS Clamp Meter, a rooftop solar contractor saves time and ensures quality panel installation by testing throughout the installation process.
MacDonald-Miller standardized on the Fluke 902 Clamp Meter when it came out several years ago.
Early reports from the field suggest that the new Fluke 772 and 773 Milliamp Process Clamp Meters may be game changers, breaking new ground for technicians in the HVAC controls industry. With the feature sets these meters offer, troubleshooting of the most common problems in modern control systems becomes a snap.
On circuits protected by GFCIs (Ground Fault Current Interrupters), leakage current can cause unnecessary and intermittent tripping. In extreme cases, it can cause a rise in voltage on accessible conductive parts.
The safety rated Fluke T+Pro gets field-tested by non-electricians. Larger buttons for gloved hands and a battery life indicator helped to make the transition from the old solenoid-based testers to the T+Pro much easier.
Accessory current clamps expand a multimeter's flexibility and measurement capabilities by allowing it to measure up to thousands of amps.
