Manfred Weber
Metra Mess- und Frequenztechnik in Radebeul e.K.
PC Vibration Measurement System VibroMetra

Order values

Order values are frequency selective. Only the signal at one frequency is measured. This frequency is determined by the key phase (rpm) input of the USB device. You can also measure at multiples or fractions of this frequency.
Order values

Signal input

1. Signal input
Selects the physical input and the gain of the USB device.
Key phase selects the input of the digital rpm sensor.

Measurand and unit

2. Measurand and unit
The connected sensor determines the available options. Velocity and displacement are calculated from acceleration by integration.


3. Characteristic
A pure sine-wave signal remains after narrow-band filtering. The following display options are available:
Peak value
Shows the magnitude
Root mean square value
Phase angle
Phase shift between the sine-wave magnitude and the  low-high slope of the digital rpm signal


4. Order
Selects multiples or fractions of the rotation frequency for band filtering.
Rotation frequency
1 : 1
Triple rotation frequency
3 : 1
Half rotation frequency
1 : 2
13/5 rotation frequency
13 : 5

Minimum speed

5. Minimum speed
The M312 is capable of detecting down to  6 1/min. However, it may take up to 10 seconds to detect  standstill. To shorten this detection time you may increase the minimum speed value. For example at  30 1/min detection will be finished after 2 second. Frequencies below 30 1/min will then be suppressed.

Suppress noise

6. Suppress noise
In order to suppress noise apart from the rotation speed more selectively, an additional filter can be used. In the dropdown list you can chose the bandwidth of the filter or switch off the filter.