Extech EX820A 1000 A True RMS AC Clamp Meter with IR Thermometer

EX820A is the Extech 1000 A true RMS AC clamp meter with a built-in non-contact infrared thermometer and laser pointer. It carries a CAT IV 600 V rating (CAT III 1000 V), a 43 mm jaw for conductors up to 750 MCM or two 500 MCM, and adds low impedance mode, a low pass filter, peak hold and inrush current capture for troubleshooting motors and drives.

Current, voltage and temperature checks in one hand

The EX820A measures AC current to 1000 A and true RMS AC and DC voltage to 1000 V, together with resistance, capacitance, frequency, diode and continuity. Its Type K input reads -20 to 760 C, while the IR thermometer with an 8:1 distance-to-spot ratio covers -50 to 270 C for hot spots on motors and bearings, so a single meter combines load current and surface temperature.

Low impedance (LoZ) mode loads the circuit to remove ghost voltages that can fool a high-impedance meter, and the low pass filter gives stable readings on variable-frequency drive outputs and other electrically noisy equipment. Inrush captures the start-up current of a motor and peak hold catches transients.

Features stated in the datasheet and manual

• 6000-count backlit LCD; true RMS current and voltage; auto power off after about 15 minutes.
• 43 mm (1.7 in) jaw; CAT IV-600 V safety rating, over-voltage category III 1000 V per manual.
• IR thermometer with Class 2 laser pointer (below 1 mW, 630 to 670 nm), fixed 0.95 emissivity.
• Supplied with industrial test leads, Type K bead wire probe and 9 V battery as described in the datasheet.

Technical specification

Measurement specification (manual)

General specification

Order codes and the EX840A alternative

The datasheet lists EX820A (1000 A true RMS AC clamp meter with IR), EX820A-NIST (with NIST certificate) and EX820A-NISTL (limited NIST). The EX840A in the same series adds 1000 A DC current; if DC current is needed choose that model.

Both models have a 6000-count display, Type K input, peak hold, inrush, LoZ and low pass filter. Confirm the code and the calibration option required before ordering.

Safety and operating notes

Use the meter only within the stated categories, keep fingers behind the barrier, and centre the conductor in the jaw. The supplied thermocouple is rated for 250 C; exceeding that can damage the probe and the meter, so use a higher-rated probe for hotter surfaces.

IR readings are affected by emissivity; the fixed 0.95 value suits most painted and oxidised surfaces but shiny metal will read low. Never point the laser at eyes.

Typical uses in Gulf plants

General engineering note: a 1000 A clamp meter with inrush and a low pass filter is a practical choice for chillers, pumps and fans with starters or drives in HVAC plant rooms, where current, voltage and a quick bearing or terminal temperature are all needed on a single visit. The IR reading complements, but does not replace, formal thermography.

Related Extech items

For AC/DC current to 400 A see the MA445, for stand-alone surface temperature the IR400, and for a logged three-phase survey the PQ3450. See the portable test and measurement category.

Field use and calibration notes

Use the meter only within its stated safety category, and wear suitable protective equipment when working on live panels. Check the test leads and the jaw before each use. When using the infrared thermometer, note the distance-to-spot ratio and the emissivity of the surface, as shiny surfaces read low. Arrange calibration at regular intervals.

Keep the meter clean and dry, store it in its case, and replace the batteries as soon as the low battery indicator appears.

Information to send with an enquiry

• Calibration certificate requirement
• Quantity

Frequently asked questions

Does the EX820A measure DC current?

No. The EX820A is an AC current model; the EX840A in the same datasheet adds DC current.

What does LoZ mode do?

It applies a low input impedance of about 2.5 to 3.5 kilohm so ghost voltages collapse and do not give false readings.

What temperature ranges does it measure?

Type K contact temperature from -20 to 760 C and infrared temperature from -50 to 270 C with an 8:1 distance-to-spot ratio.

What safety rating does it carry?

CAT IV 600 V and CAT III 1000 V for the meter, with leads of the same category, according to the manual.

Is Seven Star LLC an Extech distributor?

No. Seven Star LLC is an independent supplier in Muscat that sources Extech products on request.

Documents and quotation

Download the official Extech datasheet and manual for EX820A from this page. As an independent supplier based in Muscat, Seven Star LLC supplies Extech items on request: use the quote form with the quantity you need. Check every value in the documents against your own specification before you order. Browse similar items in the category.