Machine Diagnostics in Observer 9 Standard Rules

Transcription

1 Application Note Machine Diagnostics in Observer 9 Standard Rules Introduction The diagnostics in Observer are used as a tool to diagnose the captured data. Using machine diagnostic enables the built-in rules for detection of normal fault modes. The default modes include, for example, unbalance on fan wheels, misalignment on shaft and belt drives, and electrical frequencies on AC and DC motors. The purpose of this document is to explain the improved machine diagnostic tool that was introduced in Observer version 9.0. This document also has some important information regarding the upgrade procedure, when upgrading to Observer version 9.0. Advanced users can customize and build their own diagnostics rules, see Application Note CM3218, Machine Diagnostics in Observer 9 Private Rules. Note: The machine part tool has to be configured before the diagnosis rules can be added to the machine, see Application Note CM3213, Machine Part Tool in Observer 9. Table of contents 1. Why did the diagnostic change? What has changed? What about the alarm levels? What has happened in the graphs? What will be the benefit for me as a user? What is important for me to know during the upgrade procedure? Finally

2 1. Why did the diagnostic change? The Observer 9.0 diagnostics has a usage history of almost two decades back. The design needed some improvement to be in line with the future Observer system requirements. The technology around us and the way we use the condition monitoring system today differs vastly from how it was done two decades ago. Today, data from hundreds of machines linked together in several databases is analyzed automatically. The Observer 9 tools that were provided through the diagnostics needed an update. The diagnostics change is the first step in what we d like to call the automation initiative, meaning that we want to take away the tuning of alarm levels, manual updating of hundreds of diagnostic rules from the user and instead let the system handle this for the user. Additionally, we also want to make it easier for the user to get the most out of the condition monitoring without having the expert knowledge. 2. What has changed? 2.1. The move to the machine level First and foremost, the diagnostics are now moved from the Measurement point level to the Machine level. The diagnostics are now configured on the Machine Properties ( fig. 1). Fig. 1. The configured diagnostics for the machine. In fig. 1, it is possible to see all the diagnoses that have been added to the Diagnoses tab for this machine. In the Used points list, you can see all the measurement points for the machine that can incorporate the diagnostic logic. However, only two gearbox points Gbox In are checked for the selected machine diagnose Bearing CRB Hollow Shaft (350). Note: This means that these two measurement points are members of the currently selected diagnose, and they will produce a diagnose trend each according to the logic specified in the selected diagnose. 2

3 2.2. Link to diagnose rule In previous versions of Observer, there is no link to the diagnostic rules that the actual diagnostics was based upon. This means that once the diagnostic was attached to a point, you could not update the logic of the attached diagnoses using the specified rule. The only solution was to go through each of them one by one and edit them manually. This was a very time consuming action. In Observer 9, the diagnosis rule is directly linked to the attached diagnosis, making it much easier to fine tune the attached diagnostics by doing changes in the diagnosis rule ( fig. 2). Fig. 2. The configured diagnostics for the machine Default Search range changed The default search range setting for all diagnostics that SKF provides has been changed to 2%. This has been changed in order to make the standard diagnosis more efficient Available in the Online Repository In addition to Bearings, Machine Template and Data miner views, Machine diagnostics are now also available in the Observer Online Repository (OR). 3

4 3. What about the alarm levels? 3.1. One alarm level for all In Observer 9.0, the alarms do no longer need a manual fine tune. In the new machine diagnostics you can set one common alarm level for all the measurement points that are a member of a specific diagnose. Is it not difficult to detect a problem if there is only one alarm level? No, it isn t! In Observer 9.0, there is a new automated alarm level type called Relative. What this means is that Observer sets the normal base level (baseline level) for all measurement points and sets the alarm level to a percentage of the baseline level. Note: Each individual measurement point is checked against its own baseline level. The data from different measurement points in a diagnose is never mixed, added or subtracted between each other. Neither are data from different diagnosis mixed with each other. This means that alarm levels can, in many cases, be directly set at, for example, 200% when a new diagnosis is created, and the fine tuning of the alarm levels will not be necessary, it will all be automatic. I want to have absolute value alarm levels as I did before! It is still possible to set alarm levels to an absolute level as before, by setting the alarm type to Absolute values. However, it is only possible to set one level, and not individual levels for each measurement point in an attached diagnose. Before deciding to go with absolute levels, think about why you would want to have absolute alarm levels. Is there any specific reason for it? One of the major ideas behind the machine diagnostics is automation of diagnostic configuration and setup. If it is not necessary to manually set the alarm levels, why should we? I still want to keep my settings from before in Observer 9.0! This is not something that SKF recommends. If the user still want to have it in the same old way as it was before, you could choose No in the dialog box in fig. 5 when upgrading the database (see Section 6). In the upgrade, it will not group the previous measurement point diagnosis. Instead, the upgrade will create several (hundreds?) of machine diagnostics and assign only one measurement point to each diagnose. This is similar to as before and the system will analyze one by one to see if there are any problems. This approach will cause you to lose much of the benefits that the new machine diagnostics bring. 4

5 4. What has happened in the graphs? 4.1. Absolute values The diagnose plot, in fig. 3a, has been updated to support the new machine diagnostics. The measurement points that measure according to a specific diagnose are grouped in the same graph. This is easier to compare the different measurement points between each other. Fig. 3a shows several measurement points grouped together in one diagnose with the alarm type Absolute values. Absolute alarm levels in ge Fig. 3a. A diagnose trend showing "Absolute values" in ge. It is possible to also temporarily see how this would look like with Relative alarm levels as shown in fig. 3b. Note: The alarm levels are not shown. This is because the alarm type is set to Absolute values, and the alarm level cannot be shown when temporarily switching to Relative in the diagnose plot. Relative alarm levels in % Fig. 3b. A diagnose trend showing "Relative values" in percentage for the Low Speed Shaft (LSS) for filter ENV 1 and ENV 3 filters. 5

6 4.2. Relative If a diagnose rule has been configured to use the Relative alarm type, the diagnose plot will open a percentage on the Y-axis as seen in fig. 4a. Each measurement point shows the value in percentage of its normal level. Relative alarm levels in % Fig. 4a. A diagnose trend showing "Relative values" in percentage. Here it is also possible to temporarily switch to the other alarm type showing the real absolute values directly in the graph by right clicking in the graph and selecting type/absolute. This will display the real absolute values in the diagnose plot ( fig. 4b), but please notice that the alarm level is not visible because this diagnosis alarm type is configured as Relative, Absolute alarm levels in mm/s Fig. 4b. A diagnose showing an overall trend in "Absolute values" (mm/s). Note: If a machine is selected in the hierarchy and the Diagnose button in the toolbar is clicked, the diagnose plot will open with all the diagnoses configured for the machine. This makes it easier to analyze all the diagnoses for the entire machine. If a measurement point is selected in the hierarchy tree and the Diagnose button in the toolbar is clicked, the diagnose plot will open up with all the diagnoses that the selected measurement point is a member of. 5. What will be the benefit for me as a user? The benefits are several, but four main advantages are that it should now be: Faster to analyze Easier to setup large fleet of machine and diagnostics Easier maintenance of the diagnostics Automated analysis with less knowledge required in condition monitoring 6

7 6. What is important for me to know during the upgrade procedure? Upgrading a system to Observer 9.0 is done with the database administrator software, just like with other versions of the Observer software. Please follow the procedure outlined in the Observer Installation.pdf available on the Observer DVD. During the upgrade process of the Observer database of any previous version to Observer 9.0, the user will be prompted with the dialogue box in fig. 5. Fig. 5. Important information regarding the upgrade process. Note: The grouping of diagnosis is something that SKF recommends, but this is an irreversible choice, and cannot be changed once the system is updated. This means that if you are uncertain of which option to select, then make an up-to-date backup of the database before proceeding with the upgrade Grouping When choosing to group similar measurement points diagnostics, alternative (YES) to the database administrator tool ( fig. 5) will group the diagnostics together if they are identical. All parameters of the diagnose will be checked, such as engineering unit, number of blocks, the different block settings, calculation unit and so on. The only parameter that will not be considered in the grouping is the name of the diagnosis. 7. Finally As with all new things, there is always a learning curve before appreciating the advantages of new designs and a new way of thinking. We can understand that this, for some users, feels cumbersome and uncertain to work with, but we are confident that if you give it a chance, you will understand and feel that this is better in the end. The moving of diagnostics from measurement point level to machine level is a vital step in the continual improvement of the Observer platform. 7

8 Seals Mechatronics Bearings and housings Services Lubrication systems The Power of Knowledge Engineering Combining products, people, and applicationspecific knowledge, SKF delivers innovative solutions to equipment manufacturers and production facilities in every major industry worldwide. Having expert ise in multiple competence areas supports SKF Life Cycle Management, a proven approach to improv ing equipment reliability, optimizing operational and energy efficiency and reducing total cost of ownership. These competence areas include bearings and units, seals, lubrication systems, mecha tronics, and a wide range of services, from 3-D computer modelling to cloud-based condition monitoring and asset management services. SKF s global footprint provides SKF customers with uniform quality standards and worldwide product availability. Our local presence provides direct access to the experience, knowledge and ingenuity of SKF people. Please contact: SKF Condition Monitoring Center Luleå Aurorum 30 SE Luleå Sweden Tel: +46 (0) Fax: +46 (0) Web: SKF are registered trademarks of the SKF Group. All other trademarks are the property of their respective owners. SKF Group 2014 The contents of this publication are the copyright of the publisher and may not be reproduced (even extracts) unless prior written permission is granted. Every care has been taken to ensure the accuracy of the information contained in this publication but no liability can be accepted for any loss or damage whether direct, indirect or consequential arising out of the use of the information contained herein. PUB CM3203 EN January 2014