Environment and Site Survey Measurement
H157655_1_008
51
7.2
Magnetic Environment
The presence of any ferromagnetic materials in the immediate vicinity of the magnet will
decrease the magnets homogeneity and may degrade overall performance. Although
minimum requirements for routine NMR are not stringent, the magnetic environment must be
optimized if more sophisticated experiments are being carried out. Usually, the effect of metal
pipes, radiators, and other such objects can be “shimmed out”, but whenever possible, this
should be avoided.
7.2.1
Guidelines for Static Objects
The next table gives a list of common sources of magnetic interference for magnets. These
items should be located according to the recommendations below. It must be emphasized
however, that such recommendations represent a situation that may not be achievable.
Please consult with Bruker for possible solutions if one or more of these recommendations
cannot be satisfied.
Object
Minimum distance from magnetic center (m)
Steel reinforced walls
2
Radiators, plumbing pipes
2
Metal table, metal door
2.5
Filing cabinet, steel cabinet
2.5
Iron or steel beams
3
Massive objects, e.g. boiler
3
Table 7.5:
Guidelines for Static Magnetic Objects
7.2.2
Guidelines for Moving Objects
The table below serves as a guideline for moveable magnetic material.
Object
Actual distance from magnetic center (m)
Steel cabinet doors
3
Large metal door, hand trolley
4
Elevators*
6
Trucks, cars, fork-lifts
9
Trains, subways, trams*
30
*Elevators, trains and trams are more likely to be a source of vibrational interference.
Note that D.C. operated elevators, trains, and trams may cause disturbances over much
larger distances (see
Guidelines for DC Interference [
Table 7.6:
Guidelines for Moveable Magnetic Objects
Summary of Contents for AVANCE
Page 6: ...Contents vi H157655_1_008 ...
Page 24: ...System Components 24 H157655_1_008 ...
Page 32: ...Magnet Access and Rigging 32 H157655_1_008 ...
Page 38: ...Ceiling Height Requirements 38 H157655_1_008 ...
Page 72: ...Utility Requirements 72 H157655_1_008 ...
Page 82: ...Floor Plan 82 H157655_1_008 ...
Page 96: ...CryoProbe and Other Accessories 96 H157655_1_008 ...
Page 102: ...Contact 102 H157655_1_008 ...
Page 104: ...List of Figures 104 H157655_1_008 ...
Page 109: ...H157655_1_008 109 ...
Page 110: ...Bruker Corporation info bruker com www bruker com Order No H157655 ...