MMF VM30-H, Инструкция по эксплуатации, Страница: 33 / 58

9.5. Loading User-Defined Setups
To change quickly between different vibration quantities, filters and display modes you may
load your own user-defined setups. Press the LOAD key and select the desired setup using the
▲▼ keys. After pressing OK the VM30-H will measure with the new settings.
10. Measuring Range and Autoranging
The VM30-H has four measuring ranges which can be selected in menu “1/8: Gain”. Choose
one after the other the measuring ranges for X, Y and Z. The ranges displayed in the menu
depend on the selected vibration quantity.
Important: The measuring ranges refer to the peak amplitude before filtering and integration.
The actually displayed values may be higher when very low frequencies are measured in the
integrating modes (velocity or displacement). On the other hand, the actually displayed values
may not reach the range limits when signal frequencies in the attenuating band of the filters or
integrators are measured.
The following table shows the available measuring ranges depending on the vibration quantity
and the transducer sensitivity:
Internal
Gain
Vibration acceleration
or human vibration
1 mV/ms -2 10 mV/ms -2
Vibration velocity
1 mV/ms -2 10 mV/ms -2
Vibration displacement
1 mV/ms -2 10 mV/ms -2
100 12 m/s²
peak
1.2 m/s²
peak
120 mm/s
peak
12 mm/s
peak
1.2 mm
peak
0.120 mm
peak
10 120 m/s²
peak
12 m/s²
peak
1.2 m/s
peak
0.12 m/s
peak
12 mm
peak
1.2 mm
peak
1
1200 m/s²
peak
120 m/s²
peak
12 m/s
peak
1.2 m/s
peak
120 mm
peak
12 mm
peak
0.1
6000 m/s²
peak
600 m/s²
peak
60 m/s
peak
6 m/s
peak
600 mm
peak
60 mm
peak
The measuring ranges are selected with the ▲▼ keys and confirmed with OK.
For the display modes RMS, MTVV, PEAK, PEAK↑ and CREST an Autoranging function is
available. The autoranging function switches to a higher measuring range at 95 % of full scale
and to a lower range at 8 % of full scale.
If you have chosen autoranging, the display will show in the measuring mode GAIN UP if the
measuring range is being lowered or GAIN DOWN if the measuring range is being increased.
During the settling time of approximately 5 seconds after changing the range the VM30-H will
display OVER LOAD.
When measuring vibration total value A
hv
, the measuring range of all three channels is set
automatically to the lowest one of the three selected ranges.
Notice for the use of autoranging: If the measured vibration level should be very changeable, it
may be advisable to use fixed measuring ranges instead of autoranging to avoid continuously
changing ranges. This may also be the case if the vibration level should be near the switch limits
of 8 % or 95 % of full scale.
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