Fluke 887A

This unit is a high accuracy AC/DC Differential Voltmeter.

This unit 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.