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

Measuring procedure

Measuring procedure

Improvement of unbalance calculation

1. Improvement of unbalance calculation
After unbalance measurement VM-BAL will make suggestions for balancing and ask you whether you have implemented these suggestions. Your answers will give VM-BAL the necessary information about the current state of the rotor. By this means VM-BAL can use test runs as well as correction runs to evaluate the remaining unbalance. This can be particularly useful when a large portion of the unbalance has been compensated already and when the current vibration information is very different from the initial test runs.
You can choose for each test run whether you want to use its data for calculation. This menu option sets the default choice for balancing.

Switch option panels automatically

2. Switch option panels automatically
Balancing is performed in a given order of  actions and measurements. If the check box is enabled VM-BAL will automatically switch to the panel for the next step. You can always reset the results of the last step manually. Alternatively you may deselect this option and switch manually to the next step.

Discard incomplete vectors

3. Discard incomplete vectors
Behavior when Discard incompletely averaged vibration vectors is selected:
If a measuring run (e.g. initial run) is canceled manually, a stable speed is searched at resumption of the measurement, so that the measuring runs can start from the beginning. Likewise, the measuring run is restarted when a speed change has occured.
When this option is deactivated, a manually canceled initial run is continued, if the previous speed is reached again.
Same here when speed changes: The measurement is interrupted as long as the speed differs and continued when the initial speed is reached again. This option is for instance useful for balancing wind energy turbines, because the measurements can be later continued when wind conditions change. The previous measuring progress can also be saved as balancing history and be reloaded at a later restart of the instrument. The interrupted measurement is then continued seamlessly.

Second signal source at the same device

4. Second signal source at the same device
To simplify the configuration a second signal source is used at the same device by default. But, if the measurement channels of different USB devices shall be used for balancing, this option is disabled and a free selection can be made.