Dual-Display DMMs Give True RMS Readings

Signal analysis using dual displays, as well as a RS-232 interface, are among the several features helping make this pair of digital multimeters (DMMs) useful instruments in both lab and field settings. Models 2880A and 2890 DMMs offer two user-selectable operating resolutions (4000 and 40,000 counts) and a voltage measuring capability to 1000 vdc/750 vac, current to 10A, resistance to 40 Megaohms, and capacitance to 9999 µF. The meters can also run diode check and continuity tests, and the dual-display can handle frequencies to 200 kHz. Both DMMs offer data hold, relative mode (i.e., the difference between a set input and subsequent inputs), and maximum/minimum/average of an input. As to differences between the two DMMs, 2880A offers true rms measurements of non-linear and traditional loads, while 2890 provides both ac and ac+dc true rms readings of complex inputs.