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ADASH Ltd.
Adash 4900 – Vibrio III
Connectors
connector to plug
connector to plug in
in the sensor
headphones
(stereo jack 3.5mm)
Fig. Top view of connectors
Measuring
Screw the sensor onto the magnetic base. Do not forget to remove the plastic cover and a metal
washer (it closes a magnetic field for longer service life of the magnet) before measuring. Place the
plastic cover and the metal washer back on the magnet after measuring.
Place the magnet on a measuring point very carefully. Best is to rest the edge of the magnet on its
side and then slowly lower the sensor onto a machine. If you bring the magnet near to the machine
with its whole area hitting the machine all of the sudden, then the strong impact can irreversibly
destroy the sensor.
In case you use a measuring tip instead of the magnet, measured values are not going to be stable.
This in not surprising. The measured values depend to a large extent on a pressure of the tip at the
measurement point. The magnet that attaches the sensor generates a constant pressure so the values
are stable.
Attention!!! Use the measuring tip only in hard to reach places, where it is not possible to place the
magnetic base.
Automatic determination of the machine speed
It's important to know the speed for evaluation of the machine condition. Instrument is looking for
speed in the frequency spectrum (200Hz range).It is assumed that most of the vibration energy is
located on the speed frequency. If the instrument finds significant energy level on one frequency (that
means in very narrow band) then this frequency is labelled as the speed frequency. From this
description is clear that the speed has not to be found always. If the higher level of energy is located in
the spectrum on other line then speed frequency (for example frequency of the fan blades), then the
wrong result can be displayed.
But the correct speed, which must be defined for condition levels, can be also entered manually.
Evaluation of the machine and bearing conditions
Diagnostician is always asking a basic question after measurement: "What condition of the machine
should I assign to this measured value?"
Machine conditions are divided into 3 levels, which have the same colours like traffic lights:
1. GOOD – GREEN COLOUR
Machine is in good condition, no defect is found. The operation is without restrictions.
2. ALERT - AMBER COLOUR
The beginning defect is found on the machine. It is possible to operate with paying more attention and
planning of repair.
3. DANGER – RED COLOUR
There is a serious defect found on the machine. Machine shouldn't be in operation.
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