ADASH Ltd.
Adash 4400 – VA4Pro
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On the figures below is clear how we derived limit values. Three levels of machine condition are defined:
GOOD, ALERT (Machines lays in this range are not acceptable for a long period operation, they could be
operated till time when could be repaired) and DANGER (Vibration values in this range are considered as very
dangerous and they can cause a damage of the machine). The corresponding colors are taken from traffic
semaphore - green, amber and red.
All limit values are related to the speed value. The low speed machine should generate lower vibration then
higher speed machine.
In the graphs area you found three particular areas. The GOOD condition is the space up to the yellow line that
means operation without restriction. The space above yellow but under red line is an ALERT condition. Possible
to operate the machine but have to be more checked. It’s necessary to determine the source of worse condition
and plan repair (for instance change the bearing) or maintenance (balancing, alignment). The space above red
line is an DANGER condition and the machine should not be operated.
First figure contains the values for overall machine condition and you search unbalance, misalignment, and
mechanical looseness above all. They are called “overall” because we can measure them on most of the
measuring points. Second figure contains the limit values of a roller bearing condition. This condition is local and
can be measured only on appropriate bearing house.
Work with figures is simple. It’s necessary to know the speed. Instrument determines it automatically or user can
enter it manually. On the bottom horizontal axis you should find the point which corresponds with speed. Above
this point you will find an intersection with orange and red graph. Projections to the vertical axis will determine
limit values for amber or red state. If the measured value is lower than amber the condition is GOOD – green. If
the value is above amber but under red then the condition is ALERT – amber. If the value is higher then red
graph then the condition is DANGER – red.
