B10Vibration Test - Heraeus HS 9 Service Manual

Service Instructions HERAsafe HS/12/18
B Field tests
B10 Vibration test
Purpose of the test:
This test is performed to determine the amount of vi-
bration in an operating cabinet as an aid in minimizing
cabinet operator's fatigue and to prevent damage to
delicate tissues.
Apparatus:
Vibration analyzer with a minimum sensitivity of
0.0254 cm rms (0.001 in rms).
Calibrator for the vibration analyzer.
Calibration of the apparatus:
The vibration analyzer must be calibrated in accor-
dance with the manufacturer's instructions.
Test conditions:
Normal conditions at the place of location. Inflow and
downflow velocities at set point.
Perform test measurement:
NOTE – Segmented working plate:
For cabinets with a segmented work surface
readings should be taken at the geometric centre of
the two inner modules.
1. Fig. B12: Affix the sensing element of the vibra-
tion analyzer firmly onto the centre of the working
plate using double-faced adhesive tape.
2. Determine the background vibration amplitude
with the cabinet not operating and record the
value.
3. Turn on the cabinet and the cabinet lighting, de-
termine the vibration amplitude, and record the
value.
Valid: 05.2001 / 50060091 / A
Figure B12
Fig. B12, Measuring point for vibration test
Determine the vibration value:
Vibration value = operating value - background value
Acceptance according to NSF, 49, Annex F:
At 10-200 hertz, the deviation must not exceed 0.006
cm rms (0.002 in rms).
Troubleshooting:
Excessive cabinet vibrations:
Check the seating of the work surface.
In case of vastly excessive values, check the
blower for imbalance.
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