the service magazine of the PRÜFTECHNIK Group

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1 No.15 Hydroelectric power the service magazine of the PRÜFTECHNIK Group PRÜFTECHNIK News PRÜFTECHNIK for hydroturbines Germany is increasingly relying on renewable energy sources. Hydroelectric power is stable and reliable but only few regions have the geographic characteristics necessary for this type of energy generation. In Germany unlike in other areas of the world it is not possible to build more hydroelectric dams. Bavaria has around 4200 hydro power plants, with some of them well over 100 years old. Many an old plant is kept running by its operators with Online Condition Monitoring or mobile vibration diagnosis systems. The staff at the PRÜFTECHNIK Service & Diagnosis Center (SDIC) has had numerous opportunities to gather experience during mobile measurement calls on old hydroelectric units in historic buildings and facilities on the Isar, Inn, Danube and in the Alps, and looks forward to every single one of these assignments. Incidentally if you come to a PRÜFTECHNIK vibration seminar at the "Hotel zur Mühle" in Ismaning, Germany, you will be able to see a 40-kW hydroturbine at work next to the seminar rooms. Telediagnose No. 15 is dedicated to hydroelectric power. In this issue: High bearing temperatures in a Francis turbine Bearing clearance measurements on 15 vertical Kaplan turbines Analyzing wear in turbine bearings A well-aligned belt drive reduces vibrations Online monitoring of hydroelectric units Localizing and eliminating natural vibrations Insufficient power output in a run-ofthe-river hydroelectric unit Condition Monitoring evaluation strategies of the future 1 Condition Monitoring Service High bearing temperatures in a Francis turbine Dr. Edwin Becker, Ismaning After a major overhaul in a hydro power plant, increased bearing temperatures were noticed on a 440-hp Francis turbine with a synchronous generator rotating at 750 rpm. PRÜFTECHNIK was contracted by the operator to search for the causes using its measurement technology. Fig. 1 shows the power house with hydroelectric units that were first taken into service in Comparison with similar equipment The vibration technician had the good fortune that other hydroelectric units of the same design were still in operation. Thus, the temperature and vibrations of the units could be compared during the measurement procedure. The first step was to take vibration measurements on two of the units. It shows that the hydroelectric unit with the highest bearing temperature also had the highest rotational machine vibrations. Because there are numerous possible causes for rotational excitations in vibration ve- locities, the next step was to examine the load-dependency of these vibrations. In addition, the work performed during the last overhaul was reviewed, irregularities were discussed, and the used parts were examined. It was suspected that an unbalance of the flywheel was causing the increased vibrations. By means of field Fig. 1: Francis turbines of the same design balancing, it was possible to considerably reduce the vibrations, however, the required balancing weight was far too large. Consequently, non-contact displacement sensors were mounted on the flywheel and the radial and axial runout of the flywheel was measured with

2 Fig. 2: An accelerometer mounted horizontally on the bearing pedestal a VIBXPERT in another test run. This revealed elevated flywheel eccentricity and axial displacement of the entire shaft begins at approximately 150 kw. The operator then reported that the seat of the flywheel was out of tolerance and the fixing screws had come loose at numerous instances in the past. SDIC recommended renewing the journal bearing bushing of the flywheel or at least reworking the flywheel hub to remedy the situation. Glossary of terms Did you know? Hydro power plants which can be differentiated into hydroelectric storage plants and run-of-the-river power plants use the energy in water to generate electricity. In most cases, this is accomplished by turbines. Turbines convert the energy of flowing water into rotational motion. The shaft of the turbine is connected to a generator, which in turn converts the rotational energy of the turbine into electrical energy. The energy in water consists of the kinetic energy of the flowing water (energy of motion) and potential energy (stored energy), which takes the form of static pressure and depends on the drop height, or head, of the water. If both head h and flow rate Q of the water at a particular location are known, the electric power output P el generated by the power plant can be estimated using the following rule of thumb: P el (in kw) = 8 x Q (in m³/s) x h (in m) 2 Fig. 3: A non-contact displacement sensor for monitoring axial vibrations on the flywheel Turb.1 Full load Turb.1 Partial load stage 1 Turb.1 Partial load stage 2 Turb.1 Partial load stage 3 Turb.2 Full load Fig. 4: Frequency spectra of the vibration velocity measured horizontally on the turbine bearing. The rotational frequency is dominant on turbine 1. Francis turbine: This turbine is used in storage and run-of-the-river hydro power plants with heads of 25 to 300 m with a fairly constant water level. The water is directed through a guide wheel with adjustable blades onto the fixed blades of the impeller, which are curved in the opposite direction. The spiral infeed has a snail-shell shape. The Francis turbine is a type of reaction turbine. Its efficiency factor is approx %. Kaplan turbine: This type of reaction turbine is ideally suited for run-of-theriver hydro power plants with a high flow rate, a relatively low head of 5 to 20 m and large water volume fluctuations. With its adjustable blades, it is similar to a marine propeller. The blades of both the impeller and the guide vane apparatus can be adjusted. Its efficiency factor is approx %. Pelton turbine: These turbines are the preferred solution in large hydroelectric storage plants with large heads of m and low water volumes; they are also referred to as free jet turbines. They only make use of the kinetic energy of the water. Water emerges from jets under high pressure and strikes cupshaped blades on the impeller. Their efficiency factor is 85 90%. Cross-flow turbine: This economical turbine design is ideal for smaller storage and runof-the-river power plants with heads of 2 to 200 m and a max. power output of 1000 kw. The efficiency factor is 75 80%.

3 3 Condition Monitoring application Bearing clearance measurements on 15 Kaplan turbines Raul Ibanez, Ismaning Hydroelectric units with journal bearings that run 24/7 without interruption will continue running for decades if lubricated properly. The only aspects that limit their service life are wear and the remaining service life of components that are not designed for high fatigue strength. Wear can arise on the radial bearing, collar bearing and pilot bearings. It is differentiated into natural wear, secondary wear and wear due to forces, vibrations and/or atypical operating states. Wear development can be recorded with vibration-based movement measurements, as described below. The operator of a hydro power plant asked PRÜFTECHNIK to measure bearing clearance on vertical Kaplan turbines that each have a power output of 5240 hp and rotate at 115 rpm. Some of the machinery dates back to 1939 and still operates smoothly. Nevertheless, the operator wanted to measure the bearing clearance of the lower pilot bearing on each of the 15 units as part of its condition-based maintenance program. Because this bearing cannot be examined directly, the plan was to cause the turbine shaft to vibrate by means of specific control processes and to then draw conclusions on the bearing clearance by means of the bending line. This type of movement measurement is well within the technical expertise of PRÜFTECH- NIK. First, the accessibility of the turbine shaft had to be scheduled. Images and drawings were exchanged by , and the possible procedures were discussed. After that, the task was relatively easy. Non-contact displacement sensors were mounted close to the affected bearing points with a 90 offset and connected to the VIBXPERT. Then the shaft movements in the turbine casing were measured in multiple test runs. The radial shaft displacements that occurred during startup and shutdown were recorded and evaluated in terms of the bearing clearance. In addition, the rotational orbits and the frequency spectra of the shaft vibrations were measured. The final measurement report contained details on the irregularities found in the individual units. The measurement results and the matrix shown below were presented to the maintenance department as an aid in deciding which hydroelectric unit should be scheduled first for an overhaul. Depending on the nature of the findings, they can also be used to determine how soon the other units will need to be overhauled. Alternatively, the measurements can simply be repeated after five years, for example, to check how far wear has progressed. In any case, PRÜFTECHNIK archived the entire measurement procedure and all measurement results in OMNITREND. Location 1 Location 2 Location 3 Machine A Fig. 1: Principle of a vertical Kaplan turbine Fig. 2: Mounting the non-contact displacement sensors on the turbine shaft Fig. 3: Smileys provide a clear indication of the findings Stator Guide vane apparatus Machine B Rotor Blades Machine C Machine D NA Generator Shaft Turbine Machine E Water supply

4 Alignment application Analyzing wear in turbine bearings Alexander Schalk, Ismaning Fig. 2 shows a Kaplan turbine journal bearing shell with one-sided wear. Videoendoscopic were used to find the wear. However, the exact cause of wear was unknown. During a scheduled downtime, precision technology from PRÜFTECH- NIK was used to determine the source of the wear. The geometric tests were performed sequentially: First, a high-precision inclinometer was used to check the verticality of the unit and then the flatness of the flange (see Fig. 1). Next, a laser and detector were used to determine how precisely the bearing shells were mounted and aligned to each other (Fig. 4). It quickly became apparent that one-sided forces were acting on the lower generator bearing due to poor alignment. The cause of the one-sided wear had been found. PRÜFTECHNIK was then assigned the task of optimally aligning the entire system with laser technology during reinstallation a few weeks later. Fig.1: Use of a high-precision inclinometer (INCLINEO ) to measure the flatness of the flange headwater tail water Fig. 2: One-sided wear of the journal bearing shell Fig. 3: Graphical INCLINEO measuring report axial trust bearing generator axial trust bearing generator upper generator bearing upper generator bearing West East visible bearing wear lower generator bearing lower generator bearing 4 Fig. 4: Vertical alignment of the bearing shells with each other Fig. 5: Graphical measuring report of bearing alignment turbine bearing visible bearing wear turbine bearing

5 Condition Monitoring application A well-aligned belt drive reduces vibrations Sascha Hein, Ismaning Right in the middle of Munich, on the Isar Canal, a new hydroelectric power plant was being installed with a somewhat different design. The hydroturbine generator is driven by a very wide and relatively long flat belt. PRÜFTECHNIK was contracted by the operator to execute acceptance measurements regarding the operating and vibration behavior of the new hydroelectric unit. The general vibration behavior of the generator and turbine was acceptable. The shaft orbits, too, were only slightly elliptical and had acceptable amplitudes. Potential for optimization was found in the slow-running turbine train. Rotational vibrations and belt-related secondary vibrations were pronounced. The belt excitations were verified by means of impact tests. Because the belt tension was correct, the next step was to check the alignment using PULLALIGN. Measurements revealed that the belt pulleys were offset relative to each other. The results were documented in a measurement report for the plant operator. A few days later, the plant manufacturer contacted PRÜFTECHNIK to discuss the possible courses of action and to order a PULLALIGN. An SDIC staff member was then contracted to perform the field balancing and verification measurements. Ultimately, the excitations at the rotational frequency came to lie below 1 mm/s and the belt-related secondary vibrations disappeared entirely. PULLALIGN reflector Belt Fig. 2: PULLALIGN reflector on the belt pulley (top right). The belt is on the left. Fig. 1: Measurement setup with two displacement sensors and two accelerometers 5 How PULLALIGN works The laser transmitter and reflector are attached to the belt pulleys using magnetic brackets. The position of the laser line on both housings now provides information on the horizontal and vertical angular positions and parallel offset of the two belt pulleys relative to each other. The belt pulleys are in proper alignment when the emitted and reflected laser lines coincide with the reference lines on the PULLALIGN housing. Reflector Laser transmitter Fig. 3: PULLALIGN measurement setup on two belt pulleys (principle). Fig. 4: The position of the laser line on the PULLALIGN housing indicates whether the pulleys are misaligned.

6 Condition Monitoring application Online monitoring of hydroelectric units Johann Lösl, Ismaning While permanent diagnostic vibration monitoring is state of the art for very large hydroelectric units, small and medium-sized units generally rely only on a simple machinery protection system. Vibration monitoring is rarely employed, although developments in measuring, sensory and communication equipment have made this technology available at a far lower price than just a few years ago. Nevertheless, online monitoring should only be used to monitor components that actually have the potential of becoming damaged. Fig. 1 shows an analysis of potential sources of faults for a small hydroelectric unit with a gearbox and a generator fitted with roller bearings. Monitoring of roller bearings For small hydroelectric units that employ roller bearings, it makes sense to include envelope analyses in the Condition Monitoring program, as the following example shows. Remote monitoring of an unmanned Norwegian hydroelectric unit indicated raised excitations at the bearing outer Fig. 1: Systematic fault tree analysis, shown here for a hydroelectric unit with a gearbox Fig. 3: Envelope curves with abrupt damage development 6 Fig. 2: Accelerometers are permanently mounted on the generator for online monitoring race frequency of a generator. The vibration amplitudes abruptly and repeatedly rose to the point where the machinery had to be switched off (Fig. 3). The bearing damage found after disassembly is shown in Fig. 4. Catastrophic generator damage had narrowly been avoided. Fig. 4: Damaged outer race after disassembly

7 Monitoring of toothing Costs can run high when hydroturbines with bevel gears become damaged. The delivery times of replacement parts are long and bevel gears are expensive. Often, the preliminary stage of this type of damage is undetected bearing wear, which changes the contact pattern in the bevel gear and leads to tooth breakage. For this reason, the bevel gear should be the focus of online monitoring efforts (see Figs. 5 7). In this case, monitoring is not restricted to the overall vibration levels, but also covers the fundamental frequency of gear mesh frequency f z and its multiples. Changes in the vibration behavior and damage have not yet occurred in this plant, which is why no further images can be shown here. Monitoring of shaft vibrations Medium-sized hydroelectric units are often equipped with protective systems for monitoring shaft vibrations. In these cases, a diagnostic monitoring system is easy to retrofit (Fig. 8). For example, a VIBGUARD with voltage inputs can make use of their output signals. VIB- GUARD can also be connected to accelerometers, making it easy to retrofit equipment for monitoring housing vibrations. Incidentally, this will be a requirement in the new ISO , which will be published shortly. A thorough monitoring strategy for a hydroelectric unit is shown in Fig. 9. Fig. 5: Online monitoring with VIBNODE Band 1x f z Band 2x f z Band 3x f z Fig. 7: Frequency spectrum of the vibration velocity showing the alarm bands for gear mesh frequency f z and its multiples Fig. 6: Vibration sensor on the output shaft 7 Fig. 8: Rack for monitoring shaft vibrations Fig. 9: Online monitoring concept with VIBGUARD

8 8 Condition Monitoring Service Localizing and eliminating natural vibrations Dr. Edwin Becker, Ismaning In the course of modernization efforts, a run-of-the-river hydroelectric unit was equipped with a new, more powerful impeller. Upon startup, the unit exhibited additional noise and vibration at around 70% load that had not been present with the old impeller. The acceptance of the power plant was endangered and PRÜFTECHNIK was contracted to search for the causes. On the day of measurement, technicians used a VIBXPERT to measure the vibration behavior of the unit at various loads and to analyze the results on-site. The analysis showed that disturbances in the critical load range occurred with a slight delay and then appeared as broadband excitations in the frequency range of around 190 Hz, both acoustically and in the housing vibrations only to disappear again as the load increased further. Thus, cavitation and disturbing vibrations, which had been assumed to come from the newly wound generator, could be excluded. The only possible remaining source of vibration was natural vibrations arising from the hydroelectric unit itself. The question therefore was: Which components of this complex structure were responding to the natural frequencies? To find out, impact tests were made. First, possible vibration exciters were looked for in the dry area. Because none of the components were sensitive to vibration in the frequency range in question, the wet area of the hydroelectric unit had to be drained to be able to enter the unit. In the course of the search for the 190- Hz excitation, various impact tests were performed on the guide vane apparatus, guide equipment, blades, etc. VIBXPERT found what we were looking for on two structures: the walls in the impeller and a large guide plate. But which of these was the cause? The search was continued by excluding one of the candidates. To do this, the guide plate was temporarily tensioned until the impact test exhibited a frequency shift away from 190 Hz. After sometime when the disturbing vibration reappeared at partial load condition, it was clear that they had to come from the impeller. Yet how could the massive impeller be modified? The idea for the solution came from PRÜFTECHNIK: Chamfering the impeller by grinding down the front edge of each blade would be sufficient to eliminate the disturbance. Fig. 1: The frequency spectrum of the vibration velocity is shown logarithmically. The water tank had to be drained to enable impact tests in the wet area. Fig. 2: The front edge of each impeller blade was ground down Two days later in the evening, the happy manufacturer personally returned the borrowed VIBXPERT to Dr. Becker at his home.

9 Condition Monitoring application Insufficient output in a run-of-the-rive power plant Dr. Alvaro Chavez, Ismaning Fig. 1 Failure of a run-of-the-river hydroelectric unit to produce the predicted power output resulted in discussions between the purchaser, project leader, manufacturer and component manufacturer. Speculations on the cause high losses in the electrical equipment or excessive load vibrations made the rounds. The only way to put an end to conjecture and obtain an objective picture of the actual behavior of the hydroelectric unit was to perform mechanical torque measurements with strain gauges. The strain gauges were applied to the turbine shaft and telemetry equipment was used to establish non-contact transmission of the bridge supply and measurement data. The measurement data was recorded with a VIBXPERT signal analyzer. Beforehand, the sensitivity of the strain gauges was electrically calibrated using a shunt resistance and the Offset and Sensitivity scaling factors were set in VIBXPERT. In addition to recording the rotational speed and phases, a reflector mark was applied close to blade 1 and a laser-optical speed sensor was mounted (see Fig. 2). The measurement runs were performed that afternoon. They confirmed that the hydroelectric unit indeed did not generate the expected output. The mechanical and electrical systems, however, were operating as required. It was noticed that, beginning at a certain output, the proportionality between the supplied water quantity and the output was no longer given and the load dynamics of the impeller changed. The conclusion was that the impeller did not meet the requirements of the application and it was recommended to change the impeller geometry to achieve the required output. Fig. 1: The gear and the vertically mounted generator 2: Measurement setup for torque and rotational speed measurement 3: Characteristic line of the mechanical torque against the generator output 4: Guide wheel and impeller Fig. 2 Torque [Nm] 9 Fig. 3 Generator output [kw] Fig. 4

10 Condition Monitoring training Condition Monitoring evaluation strategies of the future Dr. Edwin Becker, Ismaning Measurement equipment is undergoing continuous development, but so is the associated evaluation technology. The best examples of this are the new possibilities afforded by cloud-supported data storage. Cloud solutions let diagnosis specialists analyze machine conditions at any time and with great flexibility even making it possible, for example, to perform diagnoses and develop corrective measures during a train ride. Once the specialist has developed solutions, he or she can use the same technology to explain the diagnoses in group sessions, discuss them in a team and develop them further. Processes of this type are called probabilistic evaluation strategies. The diagnosis result is based on the experience of the diagnosis specialist, the plant history with its tendencies regarding vibration behavior Cloud-supported Knowledge-based Data-driven Hybrid evaluation changes, and/or comparative evaluations with identical machinery. The next stage the evaluation strategy based on FMEA or FMECA was discussed in Telediagnose No. 14. In that issue, we presented examples of how valuable machine and operating experience can be utilized when working with specific components. Especially the machine coding, vibration coding and diagnosis coding, and the correction coding resulting from these, enable a systematic approach to the Condition Monitoring process. These features became available to our users with the launch of OMNITREND, version 2.9. The PRÜFTECHNIK Monitoring Center, too, uses this knowledge-based evaluation strategy to monitor over 1000 wind turbines. Fig. 1: Configuration menu of findings in OMNITREND 2.9 and higher 10 Cloud technologies make it possible to manage very large volumes of data. Whenever VIBGUARD is used, "BIG DATA" is produced at a relatively high rate. This requires the employment of data-driven evaluation technologies. Statistical evaluations are a simple form of such technologies. They can be used to derive diagnosis information from changes in statistical distributions (see Fig. 2). Other methods, such as machinebased learning (Fig. 4) or the methods of artificial intelligence, require more know-how and more mathematics. It would be wrong to think of data-driven evaluation technologies only as a means of rapidly measuring process and condition data. "Give us your raw data and we'll calculate something from it," was the opinion of a mathematician at a recent symposium. PRÜFTECHNIK is taking a different approach. Advanced Condition Monitoring systems do not simply generate data sets. They permanently preprocess data online according to the

11 specifications of the diagnosis specialist. This results in the hybrid evaluations that PRÜFTECHNIK sees as the technology of the future. Based on intelligently selected operating, process and condition data, hybrid evaluations generate diagnosis and performance information that goes far beyond the limits of previous Condition Monitoring capabilities. What measurement quantities are relevant? In the hydroelectric power sector, the following monitoring quantities (level 1) and diagnosis quantities (level 2) should be used for the hybrid evaluation strategy: a) Effective power and apparent power, measured dynamically if possible b) Vibration velocities in the frequency range from 2 to 1000 Hz as RMS and 0-P overall vibration values c) Shaft displacements and shaft vibrations as s MAX and s PP overall vibration values d) Vibration accelerations in the frequency range up to 20 khz as RMS and 0-P overall vibration values For level 2 diagnosis, the following frequency and/or order-specific diagnosis parameters are of interest: a) Characteristic values from dominant load vibrations b) Unbalance-related vibration velocities and shaft movement characteristic values c) Blade-related vibration velocity and shaft movement characteristic values d) Characteristic values for monitoring natural vibrations e) Characteristic values from orbit monitoring (unfiltered, 1st to 3rd order) This list already suggests the representational forms and single-parameter and multi-parameter evaluation methods that will be possible in the future. Exactly how the results will ultimately be represented will depend on the particular application and situation. Characteristic maps, envelope areas, sonograms and envelopes make it possible to visually compare relationships by the minute, hourly or over longer periods. Another possibility will be to evaluate multi-dimensional statistical distributions drawn from intelligent diagnostic parameters such as these. VIBGUARD was designed to perform certain evaluation routines in hydroelectric units. The best example of this is orbits, which VIBGUARD not only delivers, but also independently monitors in terms of shape, size and orientation. The future of evaluation technologies has begun. Frequency distribution Relative frequency Stable Warning Alarm Distribution function Cumulative probability Fig. 3: Sonogram as one form of representation Acceleration 11 Fig. 2: Example of a monthly statistical distribution of generator vibrations Fig. 4: Hybrid evaluation with machine-based learning methods Preview No. 16 of telediagnose.com will focus on the topic of gear drives Non-contact measurements of disturbing vibrations in an extruder gearbox Noises in a hydroturbine gearbox Measurement of load and power splitting in gear drives Preventing gearbox damage through bearing analyses

12 PRÜFTECHNIK NEWS 12 Hybrid triaxial sensor When structures move or machines shift, information on this needs to be received as early as possible. The new hybrid triaxial accelerometer VIB detects positional changes in the X and Y directions in space relative to the geocenter. It makes no difference whether the sensor is fixed in one place or moves with the machinery. During installation, the measurement axes and directions must be noted. The X and Y axes are marked on the sensor housing and produce a positive signal relative to the geocenter. A negative signal results when turned by 180. The Z axis is the symmetry axis of the sensor and points to the measured object. Not only vibrations, but also structural displacements, settling, tilting and movements can be measured with high precision using this hybrid triaxial sensor. +3 db 0 db -3 db linear k 10k Hz Frequency response VIB 6.216: Z axis +3 db 0 db -3 db linear k Frequenz 10k in Hz Hz Frequency response: X axis (black), Y axis (green) Dates Information on all trade fairs, seminars and other important events of the PRÜFTECHNIK Group can be found on our website at Industrial sensor with integrated temperature sensor One sensor one cable three measurement quantities: vibration, roller bearing condition and temperature. Suitable for connection to Online Condition Monitoring systems like VIBNODE and VIBROWEB. Mounted at the measuring location with an M8 thread fitting. Eliminates the need for extensive cabling work. Type VIB Frequency range (±3 db) 0.8 Hz khz Sensitivity 1 µa/ms-² Resonance frequency 32 khz Linearity range (±10%) 961 m/s² Temperature measurement range -20 C C Additional information can be found in the sensor catalog on our website. VIBCONNECT RF VIBCONNECT RF is now also available with a radio frequency of 2.4 GHz. This monitoring system has been successfully operating in the field for over a year now in Europe with the permitted radio frequency of 868 MHz, and in the USA with 916 MHz. For our customers in the Far East where neither of these frequencies is released we have developed a new version with 2.4 GHz. Many wireless systems only deliver simple characteristic values. VIBCON- NECT RF offers far more, providing the full bandwidth of diagnostic capabilities, namely spectra, time signals and envelope spectra. Moreover, the system is still undergoing development. A VIBCONNECT RF Sensor Unit with ATEX certification is already in the pipeline. Master Vibration Analyst CATEGORY IV... is a new course in the ISO certified seminar program. With the certification of 'CATEGORY IV Master Vibration Analyst', you will be in the premier league of vibration experts. The ISO Category IV training is designed to make even the most complex subjects relating to turbomachinery easy to understand. Online simulators support the learning experience. The very first CAT IV course in Europe has already been held at Tegernsee in May If you plan to enroll in a CAT IV course, you must already have ISO CAT III certification. VIBGUARD XP now DNV GL certified Around 10 years ago, the VIBROWEB XP online system was GLcertified for the first time. Because of its success on the market for monitoring wind turbines, an optimized version of the system with a more powerful processor was recertified about one year ago. In early 2014, VIBGUARD our Condition Monitoring flagship was certified by DNV GL under the name of VIBGUARD XP, specifically for wind turbines. This advanced CMS system offers features that far surpass the previous scope of Condition Monitoring capabilities and can, for example, communicate directly with control units via ModBus. Corporate information PRÜFTECHNIK Condition Monitoring GmbH Ismaning, Germany Tel: Fax: info@pruftechnik.com PRÜFTECHNIK Alignment Systems GmbH Ismaning, Germany Tel: Fax: info@pruftechnik.com LIT EN