Hitachi Microscope & Magnifier S-3400N User Manual

1.2.7 

1 - 11 

Type II Stage Allowable Value (high-frequency region) 

 

Frequency 

X, Y, Z-direction 

10.0 Hz 

1.0 cm/s

2

 max. 

50.0 Hz 

2.0 cm/s

2

 max. 

60.0 Hz 

2.0 cm/s

2

 max. 

 
Acceleration 4 cm/s

2

 (gal) is the same as amplitude 10 µm p-p in the frequency 10 Hz. 

The allowable values is the value at the prescribed image disturbance of 0.2 mm and at the X 
100,000 in photograph.   
 
NOTICE:  1.  A sine wave should be used for vibration measurement.     

If other than a sine wave, measurement should be made with each frequency 
component concentrated at a dominant frequency level.   

2.  For vibration at an extremely low frequency of less than 1 Hz, complete prevention 

is impossible with the vibration-isolating technology available at present.   

3.  In a frequency region from 1 to 10 Hz, interpolation should be made through each 

allowable value point.   

4.  If floor vibration exceeds the allowable values, please consult Hitachi (floor 

vibration that may cause image trouble should be measured in advance).   

5.  The above-mentioned allowable amplitude is the value with a sample size of 5 mm 

diameter.    The larger sample, the more susceptible to the effect of vibration and 
the lower the allowable amplitude. 

 
 
1.2.7  Power Line Noise and Electric Field Noise 
 
Image troubles may be observed when a device as given in Table 1.2-3 or its power line is 
installed nearby or, even if it is distant, it is a heavy-duty type.    When selecting the installation 
site, therefore, whether a source of interference is located nearby or not must be checked. 
In case an equipment energized by power of a frequency different from the commercial 
frequency employed on the Model S-3400N or the power line for it is located nearby, scan 
synchronization with power line frequency will become ineffective.    Such a location should be 
avoided.