Polytec PSV 300, Hardware Manual

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                                     
       
     
When selecting a When selecting a suitable measurement range, the maximum expected suitable measurement range, the maximum expected
values for velocity, acceleration and frequency have to be taken into values for velocity, acceleration and frequency have to be taken into
consideratio
consideration. Orientation purely on the velocity is n. Orientation purely on the velocity is often not enough, as the often not enough, as the
various measurement ranges have different bandwidths and various measurement ranges have different bandwidths and maximum maximum
acceleration accelerations. The respective values are given s. The respective values are given in the specifications (refer to in the specifications (refer to
sec sec ti ti on on 7.1 7.1 .3 .3 ). ).
Mo Most st of of th the a e app ppli lica cati tion ons a s are c re cov over ered ed by by th the 1 e 10 0 ra rang nge. e. It It sh shou ould ld th ther eref efor ore e
be selected for initial measurements with the PSV. A higher range only has to be selected for initial measurements with the PSV. A higher range only has to
be selected if the o
be selected if the overrange indicator OVER on the front of the verrange indicator OVER on the front of the controller controller
lights up permanently at scan points with high amplitude. lights up permanently at scan points with high amplitude.
F Fo or r llo ow w--ffrre eq qu ue en nc cy y a ap pp plliic ca attiio on ns s tth he e rra an ng ge es s 1 1 , , 5 5 a an nd d 2 25 5 a arre e
available. These measure available. These measurement ranges can be used from the frequency 0 ment ranges can be used from the frequency 0 Hz Hz
((ffu ulll l D DC C c ca ap pa ab biilliitty y)). . F Fo or r b bo otth h m me ea as su urre em me en nt t rra an ng ge es s 1 1 a an nd d 5 5 p plle ea as se e
pay attention to the information on setting the pay attention to the information on setting the tracking filter provided in tracking filter provided in
sec sec ti ti on on 4.2 4.2 .3 .3 ..
For high-frequency applications the top three ranges of model PSV 300-F For high-frequency applications the top three ranges of model PSV 300-F
((2
25 5 ; ; 1 12 25 5 ; ; 1 0 1 00 00 0 ) ) p prro ov viid de e a an n e ex xtte en nd de ed d ffrre eq qu ue en nc cy y rra an ng ge e o of f u up p
to 1.5 to 1.5 MHz which can be digitall MHz which can be digitally processed up to 1 y processed up to 1 MHz by the softw MHz by the software. are.
If either the positive or negative end of the measurement range is reached the If either the positive or negative end of the measurement range is reached the
overrange is indicated in the
overrange is indicated in the software and the indicator OVER on the front o software and the indicator OVER on the front off
the controller lights up. As a the controller lights up. As a general rule, the next highest measurement general rule, the next highest measurement
range should then be selected. Please note however, that the indicator is range should then be selected. Please note however, that the indicator is
activated by very short overrange already which could be
activated by very short overrange already which could be caused by noise caused by noise
spikes. In such cases the measurement range can be spikes. In such cases the measurement range can be retained as long as it retained as long as it is is
suitable for the amplitude of the r suitable for the amplitude of the required signal. Observing the signal in the equired signal. Observing the signal in the
time domain will provide clarification on this. time domain will provide clarification on this.
       
The controller is equipped with an The controller is equipped with an adjustable analog low pass filter which adjustable analog low pass filter which
adapts the bandwidth of the measurement signal to the adapts the bandwidth of the measurement signal to the application. When application. When
displaying a signal in the time domain, the signal-to-noise ratio can be displaying a signal in the time domain, the signal-to-noise ratio can be
improved by limiting the bandwidth to the necessary extent. When analyzing
improved by limiting the bandwidth to the necessary extent. When analyzing
in the frequency domain, this filter has no additional benefit. With the filter
in the frequency domain, this filter has no additional benefit. With the filter
switched on, its influence on both amplitude and phase of the velocity signal
switched on, its influence on both amplitude and phase of the velocity signal
has to be taken into consideration.
has to be taken into consideration.
Note that the software uses appropriate antialias filters which are Note that the software uses appropriate antialias filters which are
automatically adapted to the bandwidth set.
automatically adapted to the bandwidth set.
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