The Amprobe 37XR-A Digital Multimeter offers true-rms measurement along with component and logic testing for troubleshooting electronics at the bench or on the job site.

The Amprobe 37XR-A can measure inductance to 40 H, frequency to 40 MHz, capacitance to 400 µF and logic to 20 MHz. The meter has a 10,000 count display with 0.1% accuracy at selected ranges. The 37XRA measures DC voltage to 1000 V, AC voltage to 750 V, AC/DC current to 10 A, and resistance to 40 M?.

The Amprobe 37XR-A digital multimeter features an input warning tone when test leads are put in the wrong jacks; continuity beeper; Min/Max, Average, Relative, Peak and Data Hold; Auto power-off and a separate door for battery and fuse access. The Amprobe 37XR-A has a CAT III 600 V, CAT II 1000 V safety rating and is UL listed.

Why you need a True-RMS Reading Multimeter

True-RMS instruments are accurate on any AC waveform. There are two basic AC measuring systems. One is "average sensing, RMS indicating." This is the most common system because it is affordable and easy to manufacture. An instrument with this type of measuring system measures the average of a sine wave, and then multiplies it by 1.112, allowing the instrument to indicate RMS. This measuring system is only accurate on sine waves.

The second measuring method is called "RMS Sensing, RMS Indicating." An instrument with this type of measuring system computes the RMS value of the measured waveform (sine or otherwise). This is referred to as "True-RMS" reading. This measuring system is accurate for any waveform. When an average sensing instrument is used on a non-sinusoidal waveform, measurement accuracy could be off as much as 50%. Since you may not know what type of AC waveform you are measuring, a True-RMS instrument should be used whenever possible.