ETS-Lindgren 5411 GTEM! Test Cell - Manual (Page 62)

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Manual EUT Manipulator Operation Theory
Naming the EUT Faces
For the purpose of this discussion, consider the EUT as a cube. The following
illustrates a three-dimensional Cartesian coordinate system with a cube centered
on it. The face from which a positive axis emerges is named for that axis; for
example,
+X is the face of the cube from which the positive X-axis emerges.
Name the front of the EUT –Z and the back +Z. Looking at the +Z face
(the back), name the right side +Z and the left side -X. Name the top +Y and the
bottom -Y.
EUT
AS A
C
UBE ON
C
ARTESIAN
A
XES
S
HOWING
N
AMES OF
F
ACES
This is the coordinate system for the EUT. Note that the three orthogonal
positions of the EUT exchange the EUT coordinates relative to the
GTEM! coordinates. The first position is identified as
XYZ, the second as YZX,
and the third as ZXY; the voltages measured at the apex of the GTEM! in the
three positions are called V
xyz
, V
yzx
, and V
zxy
.
EUT Positions
Emissions tests all require sets of positions, which are built on the basic
three orthogonal positions needed by the three-measurement, three-input
correlation. Immunity tests require positions based on the test standard; these
are not necessarily extensions of the basic set of three orthogonal positions.