Extech 380950 80 A Mini AC/DC Clamp Meter, 1 mA Resolution

Extech 380950 80 A mini AC/DC clamp meter with 1 mA resolution

The Extech 380950 is a mini clamp multimeter with a slim, elongated jaw designed for places where an ordinary clamp cannot fit, such as dense terminal strips, small control panels, wiring ducts and automotive or HVAC wiring harnesses. It measures AC and DC current on a 4 A range with 1 mA resolution and on an 80 A range, and adds the usual multimeter functions: voltage, resistance, frequency, capacitance and duty cycle.

The jaw opens to 0.5 in (12.7 mm) and the instrument is only 200 g, so it can be used one-handed. It is supplied with test leads, two AAA batteries and a carrying case.

Technical specifications of the 380950

The figures above are from the 380950 datasheet.

How the 380950 measures low current

A clamp meter with a large jaw has trouble with small currents, because the signal is weak and the conductor does not sit tightly in the jaw. The 380950 uses a slim jaw and a 4 A range with 1 mA resolution, so it can show the 20 to 500 mA draw of control circuits, relay coils, sensor loops and small DC supplies. The datasheet quotes the 1 mA resolution on both the 4 A and the 80 A ranges. Because it handles DC current as well as AC, the same clamp can be used to check a 24 V DC control circuit or a battery charging current.

Place only one conductor in the jaw; a multicore cable carries the sum of the currents and reads close to zero. For the best reading at low current, centre the conductor in the jaw and keep other current-carrying cables away.

Where the 380950 fits among Extech clamp meters

The 380950 is a low-current specialist. For heavy motor feeders, the Extech MA1500 (1500 A) or the MA440 series cover higher current; for power, kW and power factor, the 380976-K is a power clamp. The 380950 is the tool that fits inside narrow terminal blocks and reads milliamp loops.

• Control panels and PLC cabinets: 4-20 mA loop checks on a conductor, current draw of relay coils and contactors.
• Instrument cabinets: confirm DC supply loading without breaking the circuit.
• HVAC and refrigeration: low current draw of fans, thermostats and actuators.
• Automotive and vehicle electrics: parasitic current draw tests.

Selection checklist for the 380950

• Confirm that the expected current is under 80 A and that the 1 mA resolution matters.
• Confirm that the conductor diameter fits the 12.7 mm jaw.
• Decide whether a true RMS meter is required; the datasheet does not list true RMS for this model.
• Check that 600 V voltage range is adequate for the supplies in the panel.
• Consider spare test leads and AAA batteries.

Operating and maintaining the 380950

Set the function switch to the required current range, open the jaw, enclose a single conductor and read the value. Use data hold to freeze the reading when the display is hidden behind other wiring. Disconnect the leads when measuring current with the jaw, and keep the leads away from the jaw. Replace the AAA batteries when the low battery indication appears and keep the jaw faces clean, since dirt on the mating surfaces can reduce accuracy. Do not use the 380950 on bare conductors above its voltage rating.

Applications of the 380950 in Oman and the GCC

Instrument technicians and electricians in oil and gas, power and water plants use mini clamps in cramped marshalling cabinets and local control panels. In hot, dusty sites the slim jaw makes it possible to take a reading without disturbing wiring. Electrical contractors working in commercial buildings use the same tool for HVAC fan coil and small pump circuits, where current is low.

Good measuring habits with the 380950

Small-current readings are sensitive to technique. Zero the display with the jaw closed and nothing in it if the range allows, keep the jaw faces clean and fully closed, and loop the conductor through the jaw twice to double the reading when the current is very small, then divide the displayed value by two. Keep the instrument away from strong external magnetic fields such as large transformers, because they can disturb the clamp. Record the range and the load condition with each reading so that results from different visits can be compared.

Information to send with an RFQ for the 380950

• Part number 380950 and the required quantity
• Typical current to be measured and the conductor size
• Spare leads or batteries if required
• Delivery location in Oman or the GCC and the required lead time
• Whether calibration documentation or a traceable calibration certificate is required

Documents and quotation

A datasheet for the Extech 380950 is attached on this page. It lists ranges, resolution and accuracy.

Send us the part number 380950, the quantity and the delivery location in Oman or the GCC, and we will reply with availability and a quotation. Seven Star LLC is an independent supplier in Muscat and is not affiliated with the manufacturer.