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Siemens AG Healthcare Sector 11/12 MR compatibility data sheet
12
Spatial gradient of the static magnetic field B
0
The rise of the magnetic field as a function of the distance to the magnet is expressed by
the spatial gradient of B
0
. The following figures show lines with the same gradient in T/m.
The magnetic attraction force on a magnetically saturated ferromagnetic object is propor-
tional to this quantity.
Please note: Sometimes this quantity is expressed in G/cm (1 T/m = 100 G/cm).
⊗
: At this location, the force on a magnetically saturated ferromagnetic object is greatest.
!
The iso-magnetic contour lines are accurate to a value better than 1%. There is very lit-
tle influence from the environment to the scanner. The graphic shows the cover in
nominal position. On a variety of scanners, the position can vary ±5 mm in the axial
direction. The maximum value therefore has a tolerance of ±10%, as small geometric
deviations can cause a significant change in the value.
−
0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
1.2
1.4
1.6
1.8
0.2
0
0.2
0.4
0.6
0.8
1
3 T/m 3 T/m 1 T/m 0.5 T/m 0.3 T/m 0.1 T/m
5 T/m
5 T/m
7 T/m
10 T/m
11 T/m
0.1 T
/m
0.3 T/m
0.5 T/m
1 T/m
Z Axis (m)
V
e
rt
ical (m)
Patient table
Side view