Extech MA445 400A True RMS AC/DC Clamp Meter with NCV
The Extech MA445 is a full-featured clamp meter offering true RMS measurement for both AC and DC currents up to 400 A. It also includes non-contact voltage (NCV) detection and a suite of multimeter functions, making it a versatile diagnostic tool for electricians and field technicians.
Description
The MA445 is part of Extech’s MA44x series and is built for rigorous electrical measurement tasks. Its true RMS functionality ensures accurate readings even in non-sinewave or distorted conditions. The clamp’s jaw opens to about 1.2 inches (30 mm), allowing it to accommodate fairly large conductors. The meter supports measurement of AC and DC current, AC and DC voltage up to 600 V, resistance, capacitance, frequency, temperature (via a Type-K thermocouple), diode checks, and continuity tests. Its NCV function lets you detect the presence of voltage without direct contact, which boosts safety. The display is backlit for clear readings in dim environments. Additional features include a built-in flashlight, data hold, min/max recording, and a DC zero function to null out offset when measuring DC currents. Accuracy is rated at ±2.5 % for AC current and ±2.0 % for DC current. The device is ruggedly built for field use and includes overload protection across ranges.
Features
- True RMS Measurement (AC & DC) — Maintains accuracy under distorted or non-sinusoidal waveforms.
- Current Ranges — Up to 400 A for both AC and DC (with 10 mA resolution).
- Voltage Measurement — AC/DC voltage up to 600 V.
- Wide Multimeter Functions — Resistance, capacitance, frequency, diode test, continuity.
- Temperature Measurement — Supports Type-K thermocouple input (–40 to 1000 °C, or equivalent).
- Non-Contact Voltage (NCV) — Detects presence of voltage without direct contact.
- Jaw Opening Size — Approximately 30 mm (1.2 inch), suitable for many wire sizes.
- Backlit Display & LED Flashlight — Clear viewing and built-in lighting for working in low light.
- Min/Max & Data Hold — Captures and holds readings, plus min/max tracking.
- DC Zero / Offset Removal — Allows nulling of DC offset when measuring.
- Rugged Field Design — Durable construction with overload protection on ranges.
Includes
- Complete with test leads
- Three AAA batteries
- General purpose Type K temperature probe and pouch
