True RMS AC/DC Mini Power Clamp Meter
The compact Extech 380940 is a 400A mini True RMS AC/DC power clamp meter with a small diameter jaw designed to reach in small areas while providing power calculations up to 240kW. With the added convenience of instant watt readings — a feature normally reserved for full-size meters — this mini power clamp is useful for essential troubleshooting tasks in plant maintenance, electrical, HVAC, and telecom work, as well as residential electrical repairs, energy audits, fleet maintenance, marine, and motorcycle repair.
Key Functionality
Whether you are checking amp draws on commercial electrical circuit or troubleshooting relays on vehicle air conditioning systems, the go-anywhere 0.9" (23mm) jaw opening is compact enough to fit in tight locations like engine bays. The useful data hold function freezes the display while the Min/Max function tracks and displays minimum and maximum values — useful for blind measurements and start-up draw. The zero function makes it easy to perform relative measurements. CAT II-rated, this meter is compact and easy to hold, and the 4-digit (4,000-count) readout is easy to read. Also, the 40 segment bargraph simulates an analog display, better illustrating swings in readings. In addition to power, current and voltage, the meter also measures frequency.
True RMS Compensates for Distortion from Electronic Devices
It can be very difficult to make accurate current and voltage readings in industrial and commercial applications when electronic devices are present. Fluorescent lights, motor drives, computer power supplies, and other electronic systems can distort the AC waveform, making it hard for averaging meters to get an accurate read. True RMS uses a more advanced formula to adjust for this kind of distortion.