Fluke II Series Operator's Manual page 15

Front Panel Keys (cont.)
X
Opens and closes an internal connection between
the SENSE and OUTPUT binding posts. The
Calibrator powers up with these two binding posts
connected internally (the SENSE binding posts are
open circuited), and the X indicator off. Toggling
X on (so it lights) disconnects the sense lines
from the OUTPUT binding posts.
External sensing should be used in the following
function under the stated conditions.
•
In the dc voltage function when the UUT
draws enough current to produce a significant
voltage drop in the cables.
•
In the resistance function when the UUT has a
four-wire input and the Calibrator is set to 100
kΩ or less.
•
External sensing can also be used in the two-
wire ohms function to activate two-wire
compensation circuitry to the UUT terminals.
13