lected by pressing F1 and the timer duration options of 1, 5, 15 and 60 minutes can
be selected, alternatively to deactivate the switch off timer select “none”. The auto-
matic switch off timer starts to run after the last press of a button. If a button is
pressed then the timer restarts and counts down again according to the duration se-
lected.
5. Preparation of Measuring Points
5.1. General Information on Measurement Point Choice
When monitoring machines it is important to take measurements under the same op-
erating conditions, at the same measurement point. Choosing the suitable measure-
ment point is therefore decisive.
Where possible, qualified staff experienced in machine monitoring should be called
upon.
It is generally advisable to record machine vibrations near to their source. This helps
to reduce distortion of the measuring signal to a minimum when it is being carried
through transmission parts. Suitable measurement points include rigid machine com-
ponents such as bearing housings or gearboxes.
Light or mechanically flexible machine components such as cladding and casing are
unsuitable for the measurement of vibrations.
5.2. ISO 10816-1 Recommendations
The standard ISO 10816-1 recommends bearing housings or their immediate sur-
roundings as preferred measuring location points for the measurement of machine
vibrations (Figures 9, 10, 11 and 12).
For the purpose of monitoring a rotating machine it is normally sufficient to take
measurements in only one direction, either vertically or horizontally.
On machines with horizontal shafts and rigid foundations the largest vibration am-
plitudes occur horizontally. With flexible foundations, strong vertical components
also arise.
For the purpose of acceptance tests, measurement values are to be taken from all
bearing point locations at the center of the bearing and in all three directions (verti-
cal, horizontal and axial).
The following illustrations give a few examples of suitable measurement point loca-
tions.
8
Figure 8: Shut down time
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