1. Vibration Monitoring for Gas Turbines
Steve Sabin – SETPOINT Vibration
Jan 2015

2. About content…
To activate the links and animated content in these slides, please run in “Slide Show” mode
Minden is 20 minutes from Lake Tahoe and about 45 minutes south of Reno.

3. 20 minutes from Lake Tahoe
About SETPOINT…
20 minutes from Lake Tahoe
Machinery Protection
Condition Monitoring
Minden is 20 minutes from Lake Tahoe and about 45 minutes south of Reno.

4. About me… BSEE from Oregon State University
22 years with Bently Nevada
Sales Engineer in Western Canada
TransCanada Pipelines, NOVA Pipelines, etc.
ORBIT magazine executive editor
Marketing Director
Lots and lots of articles / app notes / white papers
5 years with SETPOINT
Secretary for API 670 4th and 5th editions
Minden is 20 minutes from Lake Tahoe and about 45 minutes south of Reno.

5. Links to Resources
API 670 5th edition
1Q2005 ORBIT magazine Gas Turbine Vibration Monitoring article
Georgia Tech Short Course on Combustion Instability (“Humming”)
Video on how SETPOINT uses the PI System in place of stand-alone condition monitoring software
Minden is 20 minutes from Lake Tahoe and about 45 minutes south of Reno.
NOTE: You must be in PowerPoint Slide Show mode for these links to be active

6. Monitoring Fundamentals

7. The Industry Standard – API 670
Details sensors, monitoring systems, documentation requirements, and installation practices
Specifies accepted “good engineering practice” for machinery protection
Excellent starting point for company-specific vibration monitoring standards in all industries (not just O&G)
Developed and refined over five successive editions since first published in 1976 by a broad community of end users, instrument manufacturers, and machinery OEMs
Originally focused on bearing vibration, axial (thrust) position, bearing temperature, and gearbox casing vibration – expanded to include surge detection, overspeed, condition monitoring, and recip-specific measurements
API 670 is generally recognized as “the” industry standard for continuous vibration monitoring of critical machinery. It is referenced by many other API machinery standards such as API 626 for gas turbines, API 611 and 612 for steam turbines, API 610 for centrifugal pumps, API 613 for gears, API 617 for axial and centrifugal compressors, and API 618 for reciprocating compressors.
The standard, like all API standards, is vendor-agnostic and represents best practices compiled over the years by many different end users, machinery OEMs, EPCs, and instrument suppliers. It standardizes the signal conventions, sensor excitation voltages, minimum functionality, and other details such that sensors from one supplier can be connected to the monitor from another supplier and in turn connected to the condition monitoring software from yet another supplier. It is highly recommended that customers consider the use of API 670 as the basis for their own vibration monitoring purchasing specifications.

8. Condition Monitoring Systems
Distinctions
Protection Systems
Condition Monitoring Systems
Purpose
API 670 Scope
Displays
Platform
Vibration monitoring generally consists of two parts: machinery protection and condition monitoring. It is possible to have one and not the other – such as only protection or only condition monitoring, but this is becoming less common on critical turbomachinery which may have historically had only a protection system but now have both. Examples of various protection systems and condition monitoring software include the following:
Metrix: SETPOINT MPS is protection system, SETPOINT CMS is condition monitoring software
Bently Nevada: is protection system, System 1 is condition monitoring software
Emerson: CSI6500 is protection system, AMS Machinery Manager is condition monitoring software

9. Condition Monitoring Systems
Distinctions
Protection Systems
Condition Monitoring Systems
Purpose
Auto-Shutdown Protection High-integrity “alert” and “danger” alarms suitable for automatically tripping the machine – no operator intervention required.
API 670 Scope
Displays
Platform
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

10. Condition Monitoring Systems
Distinctions
Protection Systems
Condition Monitoring Systems
Purpose
Auto-Shutdown Protection High-integrity “alert” and “danger” alarms suitable for automatically tripping the machine – no operator intervention required.
Information Delivery High-resolution data for machinery engineers to analyze for run/don’t run decisions, outage planning, root cause diagnostics, etc.
API 670 Scope
Displays
Platform
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

11. Condition Monitoring Systems
Distinctions
Protection Systems
Condition Monitoring Systems
Purpose
Auto-Shutdown Protection High-integrity “alert” and “danger” alarms suitable for automatically tripping the machine – no operator intervention required.
Information Delivery High-resolution data for machinery engineers to analyze for run/don’t run decisions, outage planning, root cause diagnostics, etc.
API 670 Scope
Normative Historic focus of 1st through 5th editions
Displays
Platform
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

12. Condition Monitoring Systems
Distinctions
Protection Systems
Condition Monitoring Systems
Purpose
Auto-Shutdown Protection High-integrity “alert” and “danger” alarms suitable for automatically tripping the machine – no operator intervention required.
Information Delivery High-resolution data for machinery engineers to analyze for run/don’t run decisions, outage planning, root cause diagnostics, etc.
API 670 Scope
Normative Historic focus of 1st through 5th editions
Informative New in 5th edition as an “Informative Annex”
Displays
Platform
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

13. Condition Monitoring Systems
Distinctions
Protection Systems
Condition Monitoring Systems
Purpose
Auto-Shutdown Protection High-integrity “alert” and “danger” alarms suitable for automatically tripping the machine – no operator intervention required.
Information Delivery High-resolution data for machinery engineers to analyze for run/don’t run decisions, outage planning, root cause diagnostics, etc.
API 670 Scope
Normative Historic focus of 1st through 5th editions
Informative New in 5th edition as an “Informative Annex”
Displays
Basic (bargraphs / status / trends) Intended for operators – often via DCS screens; local display at racks are optional but frequently included
Platform
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

14. Condition Monitoring Systems
Distinctions
Protection Systems
Condition Monitoring Systems
Purpose
Auto-Shutdown Protection High-integrity “alert” and “danger” alarms suitable for automatically tripping the machine – no operator intervention required.
Information Delivery High-resolution data for machinery engineers to analyze for run/don’t run decisions, outage planning, root cause diagnostics, etc.
API 670 Scope
Normative Historic focus of 1st through 5th editions
Informative New in 5th edition as an “Informative Annex”
Displays
Basic (bargraphs / status / trends) Intended for operators – often via DCS screens; local display at racks are optional but frequently included
Detailed (waveforms, orbits, spectrums, etc) Intended for machinery experts; often via remote access to a local server in the plant collecting and storing the data
Platform
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

15. Condition Monitoring Systems
Distinctions
Protection Systems
Condition Monitoring Systems
Purpose
Auto-Shutdown Protection High-integrity “alert” and “danger” alarms suitable for automatically tripping the machine – no operator intervention required.
Information Delivery High-resolution data for machinery engineers to analyze for run/don’t run decisions, outage planning, root cause diagnostics, etc.
API 670 Scope
Normative Historic focus of 1st through 5th editions
Informative New in 5th edition as an “Informative Annex”
Displays
Basic (bargraphs / status / trends) Intended for operators – often via DCS screens; local display at racks are optional but frequently included
Detailed (waveforms, orbits, spectrums, etc) Intended for machinery experts; often via remote access to a local server in the plant collecting and storing the data
Platform
Hardware Intended strictly for machinery protection; usually rack-based; not simply transmitters into PLCs or DCSs
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

16. Condition Monitoring Systems
Distinctions
Protection Systems
Condition Monitoring Systems
Purpose
Auto-Shutdown Protection High-integrity “alert” and “danger” alarms suitable for automatically tripping the machine – no operator intervention required.
Information Delivery High-resolution data for machinery engineers to analyze for run/don’t run decisions, outage planning, root cause diagnostics, etc.
API 670 Scope
Normative Historic focus of 1st through 5th editions
Informative New in 5th edition as an “Informative Annex”
Displays
Basic (bargraphs / status / trends) Intended for operators – often via DCS screens; local display at racks are optional but frequently included
Detailed (waveforms, orbits, spectrums, etc) Intended for machinery experts; often via remote access to a local server in the plant collecting and storing the data
Platform
Hardware Intended strictly for machinery protection; usually rack-based; not simply transmitters into PLCs or DCSs
Software Generally computer-based; uses Microsoft business/consumer operating systems
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

17. Radial Vibration Displacement (mils pk-pk) Y-probe X-probe
Radial vibration is measured with shaft-observing proximity probes. We generally install two probes that are orthogonal (i.e., 90 degrees apart) so that we can see radial motion in all directions. Each probe sees the total excursion of the shaft towards and away from the probe, along its own axis. By combining the signal from these two probes, we can visualize the shaft orbital motion as it vibrates. Because we are interested in the total excursion of the shaft, we measure the peak-to-peak displacement. In North America, mils (thousandths of an inch) are generally used. In the rest of the world, metric units (micrometers) are generally used. Notice that the vibration at the y-probe is smaller than at the x-probe, due to the elliptical shape of the orbit and therefore the amount of vibration the probes “see” in their respective axes. Because the amount of vibration typically varies in each axis, X-Y probes are routinely used for protective purposes. X-Y probes also ensure that diagnostics can be done to observe the orbit shape – something not possible when only a single probe is used.

18. Casing Vibration Velocity (in/sec 0-pk)
Unlike shaft observing probes, casing transducers measure the vibration on the machine’s case (not at the rotor). As the animation shows, the casing vibration sensor (also known as a “seismic” vibration sensor) measures case vibration, not shaft vibration. Thus, the casing measurement relies on a sufficient amount of vibration being transmitted from the shaft out to the casing. For some machines, this is a good assumption, but for other machines, it is not. For example, when a machine has a very light rotor and a very heavy case, very little vibration may be transmitted to the case, and this can be exacerbated by seals, process gases surrounding the rotor, lubricating oil wedges supporting the shaft in each bearing, and other factors that may combine to further dampen the vibration. Thus casing measurements are appropriate only when a significant amount of shaft vibration is transmitted to the machine casing. In almost all instances where machines use fluid-film bearings, proximity probes are recommended such that actual shaft vibration is observed, but this may be augmented by casing vibration in some situations such as machines with heavy rotors and relatively light casings (such as some steam and gas turbines).
Many machines will have a mix of shaft vibration and casing vibration measurements because each measurement provides different information. For example, casing measurements on a gearbox will provide information on gear meshing frequencies and alert operators to broken teeth and other malfunctions. Likewise, shaft-observing proximity probes on the gearbox will convey bearing-related (rather than gear-tooth related) problems.
For machines that use rolling element bearings instead of fluid-film bearings, casing vibration is almost always used instead of shaft-observing proximity probes. This is because the rotor is very rigidly coupled to the machine case through the bearings and metal-to-metal contact is occurring, unlike fluid-film bearings that “cushion” the rotor from the machine casing by an oil wedge and intentional diametral clearances inside the bearing.
When measuring casing vibration, we are usually not as interested in the physical displacement as we are in the amount of vibratory energy, and thus pk (instead of pk-pk) amplitude is measured. Some customers, particularly those in Europe, prefer to measure in RMS instead of pk. Casing vibration is usually measured with an accelerometer which provides an output in g’s. This signal can be integrated to units of velocity if desired, and many machine manufacturers publish allowable casing vibration levels in units of velocity. In other instances, casing vibration is measured with a sensor that intrinsically measures velocity. A moving-coil velocity sensor is an example of this – it provides an output in velocity (does not integrate from acceleration to velocity).

19. Axial (Thrust) Position
Gap (mils)
Can configure for:
increasing gap upscale* (normal)
increasing gap downscale (counter)
*increasing gap upscale depicted here
NORMAL
COUNTER
Probe
Axial position looks at the average gap (not instantaneous gap) between the probe and the shaft. If we think of the signal as consisting of an AC component (the instantaneous position that changes during vibration) and a DC component (the average position), an axial measurement looks only at this DC component of the signal. Axial position is an extremely important measurement as excessive axial movement will generally mean that rotating parts (such as blades) are contacting static parts (such as guide vanes). As such, axial position is almost always connected to auto-shutdown.
The nature of the axial measurement is such that the shaft can move so much during a thrust bearing failure that the probe tip either rubs the shaft at one extreme or moves outside the probe’s linear range at the other extreme. For this reason, it is considered good engineering practice (and a requirement of API 670) to use two axial probes and use AND voting between them. This makes it easier to distinguish a probe NOT OK condition from actual excessive shaft movement by requiring both probes to observe the same thing and using 2-out-of-2 voting. This is why you will often hear axial position measurements referred to as “dual voting thrust position.” The diagram here shows only a single probe, but the use of two probes is straightforward. Each probe would go to its respective channel of the monitoring system and with both probes operating normally, each channel will observe the same movement. If one probe fails, the monitoring system will normally bypass the failed channel and revert to a single-voting measurement. Some customers elect to use a NOT OK probe as a vote to shut down in the 2-out-of-2 voting logic. Others do not allow a shutdown when one probe is NOT OK. The monitor allows either voting scheme to be implemented.

20. Eccentricity Indicates amount of shaft bow
Typically measured at a shaft extreme
Slow-roll speeds (well below rotordynamic effects)
Axial position looks at the average gap (not instantaneous gap) between the probe and the shaft. If we think of the signal as consisting of an AC component (the instantaneous position that changes during vibration) and a DC component (the average position), an axial measurement looks only at this DC component of the signal. Axial position is an extremely important measurement as excessive axial movement will generally mean that rotating parts (such as blades) are contacting static parts (such as guide vanes). As such, axial position is almost always connected to auto-shutdown.
The nature of the axial measurement is such that the shaft can move so much during a thrust bearing failure that the probe tip either rubs the shaft at one extreme or moves outside the probe’s linear range at the other extreme. For this reason, it is considered good engineering practice (and a requirement of API 670) to use two axial probes and use AND voting between them. This makes it easier to distinguish a probe NOT OK condition from actual excessive shaft movement by requiring both probes to observe the same thing and using 2-out-of-2 voting. This is why you will often hear axial position measurements referred to as “dual voting thrust position.” The diagram here shows only a single probe, but the use of two probes is straightforward. Each probe would go to its respective channel of the monitoring system and with both probes operating normally, each channel will observe the same movement. If one probe fails, the monitoring system will normally bypass the failed channel and revert to a single-voting measurement. Some customers elect to use a NOT OK probe as a vote to shut down in the 2-out-of-2 voting logic. Others do not allow a shutdown when one probe is NOT OK. The monitor allows either voting scheme to be implemented.

21. Phase / Speed Pulses/min (rpm)
For speed measurements, we normally recommend a multi-tooth wheel instead of a once-per-turn notch (or projection) as shown here. The idea is the same – count pulses per unit time and divide by the number of teeth to obtain shaft revolutions per unit time, and thus speed.
Phase can be thought of as a timing mark in an automotive engine – it defines the precise rotative position of the shaft at a moment in time, so that vibration signals can be referenced to it to compare phase angles, to filter to running speed (1X) and multiples of running speed (nX), etc.

22. Reverse Rotation CW Rotation
Reverse rotation can be damaging on some machines, such as those with dry gas seals. It can be measured with two proximity probes observing a single notch or keyway as shown here. When the shaft is rotating on the clockwise direction, the notch will be seen by the blue probe before it is seen by the yellow probe. The monitoring system can detect the order of the pulses (blue before yellow versus yellow before blue) and thus determine direction of rotation.

23. Reverse Rotation CCW Rotation Peak reverse speed
# of reverse rotations
Here we rotate the shaft in the opposite direction (counter-clockwise) and now the yellow probe will detect the notch prior to the blue probe.
For some machinery applications, the peak speed incurred during a reverse rotation event is important. For others, the cumulative number of revolutions in the reverse direction is important. The reverse rotation monitor should be capable of measuring both of these. It can also serve as a standard tachometer, as it can measure speed. And, one of the probes can serve as a phase trigger reference, since there is only a single notch or projection being observed (i.e., once-per-turn signal).

24. Temperature Measurements
Bearing metal temperature measurements are covered in API 670 and are often included in the machinery protection system, since they are machinery temperatures, not process temperatures
Other temperatures in machinery are sometimes measured as well:
Electric motors – winding temperatures
Gas turbines – exhaust temperatures
Recip compressors – valve temperatures
Temperature is usually measured with RTDs or thermocouples. API 670 monitoring systems must be able to accept both kinds of sensors, in a variety of materials (100 ohm platinum RTDs, 10 ohm copper RTDs, J-type thermocouples, K-type thermocouples, etc.) and provide appropriate alarming. API 670 also provides extensive guidance on where to mount the bearing metal temperature sensing elements, as shown in this excerpt from 670 4th edition.

25. Machinery Protection System
Conceptual Overview
Monitors
Sensors
Machinery Protection System
Bearings
Machine Cases
Shafts
Turbine
Generator
This graphic shows conceptually how the shaft vibration is detected by sensors (in this case, radial vibration at the generator non-drive end) and input to the machinery protection system. Notice that the orbit shape is elliptical, which is very typical for real-world machinery. Consequently, the probe on the left sees less vibration amplitude than the probe on the right. Further, based on the alarm amplitudes set, the left-hand probe is not in an alarm condition while the probe on the right is in an alarm condition (Danger, in this case). Depending on the customer’s machinery protection philosophy, they may allow a single probe to shut the machine down, or they may use it for operator alarm annunciation only. The machinery protection system has extensive logic capabilities to vote various statuses from various channels in complex ways, allowing customers significant flexibility in their alarm voting logic and shutdown philosophies.

26. Typical Probe Mounting
This graphic shows conceptually how the shaft vibration is detected by sensors (in this case, radial vibration at the generator non-drive end) and input to the machinery protection system. Notice that the orbit shape is elliptical, which is very typical for real-world machinery. Consequently, the probe on the left sees less vibration amplitude than the probe on the right. Further, based on the alarm amplitudes set, the left-hand probe is not in an alarm condition while the probe on the right is in an alarm condition (Danger, in this case). Depending on the customer’s machinery protection philosophy, they may allow a single probe to shut the machine down, or they may use it for operator alarm annunciation only. The machinery protection system has extensive logic capabilities to vote various statuses from various channels in complex ways, allowing customers significant flexibility in their alarm voting logic and shutdown philosophies.
image courtesy of Elliott Group

27. Typical Transducer Arrangement

28. Typical System Arrangement
8 x 4-channel monitors for 30 vib’n, thrust, speed, and phase inputs
3 x 6-channel monitors for 16 temp inputs
Local HMI
Condition Monitoring SW
Redundant MODBUS® links with DCS
4-20mA and relay outputs
Fully redundant power connections to 24Vdc supplies

29. Typical Local HMI
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

30. Typical Condition Monitoring Plots
Orbit / Timebase
Trends
Bode
Polar
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

31. Typical Condition Monitoring Plots
Spectrum
Alarm List
Waterfall
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

32. Gas Turbine Classifications

33. Classifications Industrial (i.e. Heavy Duty) Aeroderivative
Fluid-film bearings
Solely for industrial use
Heavy / Large /Foundation-mounted
Always single-spool; often single-shaft
Conventional maintenance
Rolling-element bearings
Adapted from aircraft engine design
Lightweight / Compact / Skid-mounted
Often multi-spool GG driving a PT
Swap-out maintenance
SGT6-2000E (103 MW)
FT4000 SWIFTPAC®
(60 MW)
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

34. Sub-Classifications “Light” Industrial Hybrid
All-industrial components
Fluid-film bearings
Skid-mounted / packaged
Part-aero / Part-industrial components
Mix of bearing types
Multi-spool/shaft
MS6001FA (LP compressor) + LM6000 (HP compressor and HP/IP turbine)
Centaur 40 (50 MW)
LMS100
(~100 MW)
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

35. Major Manufacturers Industrial Aeroderivative
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36. Brands, Acquisitions, and Mergers
x 106
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(but mostly convergence)

37. Monitoring Considerations

38. Aeroderivative Nomenclature
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(Image courtesy of ORBIT magazine)

39. Aerodynamically-Coupled Gas Turbine
Multi-Spool Aeros
Typical 1-Spool GG
Typical 2-Spool GG (shown in figure below)
Typical 3-Spool GG
LM2500
GE LM6000
Rolls-Royce RB211
GE LM1600
Rolls-Royce TRENT
Aerodynamically-Coupled Gas Turbine
2-Spool Gas Generator HP HP
Driven Machine (pump, generator, compressor, etc.) LP
HP Spool LP
Power
Comp
LP Spool
Turb
Turb
Comp
HP Spool
Turb
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40. Monitoring Philosophies
Industrial
Aeroderivative
Fluid-film bearings  Proximity
Heavily instrumented  6-12 sensors
Conventional maintenance
Engine problem = loss of product
Relatively OEM-independent
Relatively “clean” vibration signals
Rolling-element bearings  Siesmic
Lightly instrumented  1-3 sensors
Swap-out maintenance
Engine problem = loss of life
Extremely OEM-dependent
Extremely noisy vibration signals (lots of signal processing required)
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

41. Recommended Monitoring
INDUSTRIAL
Measurement
Description
MINIMAL TRANSDUCER SUITE
Radial Bearings
Thrust Bearings
Shaft Speed / Phase
X-Y proximity probes
Dual-voting axial probes
Once-per-turn phase reference probe
SUPPLEMENTAL FOR LARGE FRAME SIZES
Casing Vibration*
Eccentricity
Seismic velocity at bearing caps
Proximity probe for rotor sag or bow
* NOTE: GE frame-type gas turbines use only seismic bearing cap vibration for shutdown protection; proximity probes on radial bearings are used only for condition monitoring.
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

42. Recommended Monitoring
AERODERIVATIVE
Measurement
Description
ENGINE
Casing Vibration
Shaft Speed
Seismic at OEM-specified locations with OEM-specified filtering (primarily 1X)
Multi-tooth gear for each spool speed
POWER TURBINE
Rolling Element Bearings
Fluid Film Bearings
Radial Bearings
Thrust Bearings
Shaft Speed/Phase
Seismic velocity at OEM-specified locations
X-Y proximity probes
Dual-voting axial probes
Once-per-turn phase reference probe
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

43. Typical OEM-Specified Schema
GE IDM FOR AERODERIVATIVES
Monitor
Monitor each 1X for blade loss events
Fast (100 mS) danger level time delay trip
1 second time delay on alarm levels
Monitor filtered Hz wideband for “other” engine problems
10 second time delay alarm
10 second danger level to trip
Have unfiltered accel signal available for diagnostics (not used for monitoring)
COOL
 1X velocity tracked at spool speed
Control Room
 Raw Acceleration (10 mV/g)
 Wideband Velocity @ Hz (100mV/ips)
Spool Speed x gear ratio
Field
Interface Module
WARM
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HOT
50 pC/g
Accel

44. Why Velocity and not Accel?
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45. Exhaust Gas Temperature
Ideally measured at turbine inlet, (but usually too hot there!)
Measured at tubine exhaust plenum instead (via thermocouples placed circumferentially)
Indicates problems in hot gas path
Can be used for both control and monitoring
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets
Typical exhaust gas temperature profile
(Screen capture from GE System 1 software)

46. Combustor Instability (Humming)
Huge issue with DLE engines
Excellent short course by Georgia Tech’s Tim Lieuwen (click on screen at right for link to course slides)
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

47. “Humming” Monitoring
Monitored with dynamic pressure transducers observing pulsations in combustor cans – often with stand-off tubes
Proprietary OEM schemas for sophisticated narrow-band frequency monitoring (often 12-pole or better roll-off required)
Used as part of feedback control loop to adjust fuel mixture if humming occurs
Pressure Sensor
Control Target: “As lean as possible without humming”
Combustion
Control
“Humming” Monitor
Combustor
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48. Typical Gas Turbine Transducers
High-Temperature Moving-Coil Velocity Sensor
(Metrix 5485C)
High-Temperature Accelerometer Sensor
(Metrix SA6350)
Proximity Sensor
(Metrix MX2030)
High-Temperature Pressure Sensor
(Kistler)
Release 2.0 will support additional plot types as shown by the toolbar and by the italicized bullets

49. Recommended Reading
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50. Q&A