MHC Instrument Super Slo Mode
Super Slo mode is designed for monitoring machinery rotating at speeds between 0.25 rpm and 60 rpm. Such slow speed machinery is very difficult to monitor with traditional Vibration techniques but is straightforward for AE. The only information which needs to be known to set up a Super Slo measurement is the approximate time for the item being monitored to complete a revolution.
The incoming AE signals are processed in terms of the four parameters, a brief description of each is given below:
1 - dB Level
This is the same parameter as used in Standard Mode. On slow speed machinery dB Level values are typically very low. An increase in dB Level may occur where there is increased friction or very close to final failure.
2 - Peak
This is the averaged Peak value for each of the 8 revolutions. Peak is of most use for the detection of gross singular faults such as a cracked race.
3 - Extent®
This is a measure of the percentage of the rotational cycle in which there is significant transient activity. Progressive deterioration typically shows an increase in Extent® from around 5% or less to more than 50% when damage is widespread. Extent® is also a very useful instant indicator of the presence or appearance of a problem.
4 - Intensity
This is a measure of the average amplitude of the detected AE activity within those regions contributing to the Extent® reading. The Intensity value can be useful in qualifying a high Extent® reading (e.g. a high Extent® coupled with a low intensity might indicate widespread minor damage).