Extech 380580 – Battery Powered Milliohm Meter

• Invalid test indicators prevent inaccurate measurements
• Built-in water resistant case with shoulder strap
• Four terminal Kelvin measurements
• Over-temperature and over-voltage protection
• 5 ranges with 100µOhm max resolution

The 380580 is a Battery Powered Milliohm Meter. This milliohm meter features high accuracy, a high resolution, portable milliohm meter battery operated for field use, four-terminal Kelvin measurements, and Over-temperature and over-voltage protection. battery operated to facilitate in-the-field use, Extech’s 380580 Milliohm Meter provides five resistance ranges with resolution as low as 0.1 milliohms, and the 4-wire Kelvin clip connection provides optimum accuracy. Typical applications include a transformer, motor coil, and PC board resistance measurements.

Additional Features

Measurements are displayed on a large, 2000 count LCD. Additional features include over-temperature and over-voltage protection, Auto-Hold, Auto power off, and invalid test indicators to prevent inaccurate measurement.

What is MilliOhm?

The units of measure for resistance less than 1 Ohm (Ω) are Milli- (mΩ) and Micro-(μΩ)Ohms. One MilliOhm (1mΩ) is equal to one-thousandth of an ohm (0.001). One MicroOhm (1μΩ) is equal to one-millionth of an ohm (0.000001). For example, 0.5 ohms (one half an ohm) is equal to 500mΩ.

Why are 4-wire connections required when making milliohm measurements?

Test leads always introduce a small amount of additional resistance to a measurement. This is acceptable in non-critical measurements such as megohm resistances. However, when measuring milliohms in a critical application, any additional resistance can render the measurement useless. This is why 4-wire (Kelvin) connections are imperative.