The Extech EX400A Series is a family of four professional handheld digital multimeters covering general-purpose electrical troubleshooting through advanced measurement work with integrated non-contact temperature. The lineup includes the EX410A averaging manual-ranging meter, the EX411A True RMS manual-ranging meter, the EX430A True RMS autoranging meter with capacitance and frequency, and the EX470A True RMS autoranging meter that adds a built-in infrared thermometer. All four models share the same physical platform — 7.4 × 3.2 × 2 inch chassis weighing 0.75 lb — with a large backlit LCD using 1-inch digits, a built-in Type K thermocouple input, low-current measurement down to 0.1 µA, input fuse protection, and CAT III-rated test leads.

A handheld digital multimeter is the universal field and bench instrument for measuring voltage, current, and resistance — the three fundamental electrical quantities. Professional-grade DMMs add diode test, continuity, temperature, and often capacitance and frequency, making them the first instrument an electrician, field service technician, or maintenance engineer reaches for when diagnosing an electrical problem. The EX400A Series is positioned for that work: industrial maintenance, electrical troubleshooting, HVAC and motor service, and general bench use where a single rugged instrument needs to cover the everyday measurements an electronics or electrical professional makes.

ValueTronics has been a primary U.S. source for Extech and Extech-by-FLIR handheld test instruments since the brand's distribution expansion in North America. Equipment is stocked and tested at our 20,000 sq ft secure warehouse at 1675 Cambridge Drive, Elgin, Illinois — a facility we operate to support both new authorized distribution and our verified used and refurbished inventory. Handheld DMMs like the EX400A Series are among the highest-frequency repeat-purchase items in our catalog, and we stock them new with full manufacturer warranty alongside our broader handheld instrument inventory.

Brand Heritage

Extech Instruments was acquired by FLIR Systems in 2007 and has operated as Extech-by-FLIR since the acquisition, expanding from its handheld electrical-test heritage to include thermal-adjacent products that leverage FLIR's IR-sensor technology. FLIR Systems itself was acquired by Teledyne Technologies in 2021; the Extech, FLIR, and Teledyne FLIR brand identities are all maintained under the current corporate structure, with handheld instruments like the EX400A Series continuing under the Extech brand.

Compare Other Models in This Series

The Extech EX400A Series is a tiered family of four handheld professional multimeters built on a shared mechanical and display platform. The four models differ in three principal dimensions: measurement architecture (averaging vs. True RMS), ranging (manual vs. autoranging), and advanced functions (capacitance/frequency/duty-cycle and the built-in IR thermometer on the EX470A). All four share the same chassis, the same backlit 1-inch-digit LCD, the same Type K thermocouple input, the same 600 V / 10 A AC and DC ranges, the same low-current 0.1 µA capability on DC, and the same CAT III-rated test leads and accessory bundle.

Choosing the correct model is principally an application question: is the work general electrical troubleshooting on sine-wave loads (EX410A), professional work on distorted waveforms requiring True RMS (EX411A and above), work that also requires capacitance and frequency measurement (EX430A and EX470A), or work that also requires non-contact surface temperature measurement (EX470A only). Each step up the family adds capability without changing the underlying chassis, controls, or accessory set.

Each new EX400A Series model below is listed on its own dedicated product page with condition-matched pricing and warranty terms appropriate to the model and condition tier. Use the comparison information that follows to identify the model that fits your measurement requirement, then visit the individual model page for current pricing, availability, and accessory configuration.

The two manual-ranging models (EX410A and EX411A) are differentiated solely by measurement architecture: the EX410A uses averaging AC measurement with ±0.5% basic DC accuracy, while the EX411A adds True RMS measurement and improves basic DC accuracy to ±0.3%. Both cover the same V/A/Ω ranges, both include the Type K thermometer, and both carry the same 1-year warranty. The EX410A is the right choice when the AC measurements involved are confirmed sine-wave (clean mains, resistive loads); the EX411A is the right choice for any work that may involve VFDs, switching supplies, or other non-sinusoidal current and voltage signatures.

The two autoranging True RMS models (EX430A and EX470A) add capacitance (0.01 nF–100 µF), frequency (0.001 Hz–10 MHz), and duty-cycle (0.1–99.9%) measurement, plus a relative function, and both carry the longer 3-year warranty. Resistance range extends from 20 MΩ on the manual-ranging models to 40 MΩ on the autoranging models, and AC current resolution improves to 0.1 µA. The EX470A adds the built-in non-contact infrared thermometer (58 to 518°F / -50 to 270°C) — making it the single-instrument choice for technicians who routinely need both electrical measurements and surface-temperature readings (motor bearings, electrical-panel hot spots, HVAC equipment) without carrying a separate IR pyrometer. For users who do not need non-contact temperature, the EX430A delivers the same electrical capabilities at lower cost.

Additional differences in specifications beyond the few shown above are not listed here — see each model's full specifications below.

Accessories Supplied

• CAT III test leads
• Multi-position tilt stand
• Velcro strap for hanging
• Protective holster with test lead holder
• Bead wire temperature probe
• 9V battery

Product Core & Specifications

Please review the Manufacturer's Data Sheet to verify published specifications. Feedback on this webpage is always welcome — please reach out to your Test Architect at any time for questions or concerns. Thank you, we truly appreciate you being our customer.