Fluke 883AB

The 883AB is a high accuracy AC/DC Differential Voltmeter. Differential voltmeters measure voltage by bucking the unknown voltage against an internal reference voltage using a Kelvin-Varley Divider. When at null it presents an extremely high input impedance to even high impedance sources. This reduces measurement errors due to loading. TVM mode configures the panel meter to indicate polarity and determine the correct voltage range. Null mode configures the panel meter to monitor the kelvin-varley divider output with four increasingly sensitive null ranges. Basic dc voltage accuracy is 0.01% of indicated value + 5 MicroV. Resolution is 1 MicroV. The unit can be battery or line-powered.