Condition monitoring
solutions for hydroelectric
power generation

Why the Bently Nevada
product line?

We understandhow to monitor yourhydro machineryWe have earned your trust. For over six decades the
Bently Nevada product line has supported the most demanding
applications in multiple industries. And even as we protect andmonitor your machinery, we constantly strive to refine andimprove our offerings—and help enable your success.

Whether Kaplan, Pelton, Francis, bulb, or propeller—vertical or horizontal—
generation-only or pump/storage, our hydro monitoring solutions are effective
because we understand the measurements you need to detect the uniquemalfunctions that can affect hydro units. In addition to the traditional proximity,
velocity, LVDT, and acceleration measurements, our solutions incorporate a widearray of sensors designed specifically for hydro power applications.

Over 60 years of condition
monitoring leadership
330505 Low-Frequency Seismic Sensor

This sensor eliminates low frequency noise that other sensor technologies exhibit,
and reliably detects vibration at bearing supports where vibration is often a sign ofsignificant machine problems. It can also be applied at the stator core and frame,
where vibration can damage winding insulation.

4000 Series Air Gap Sensor System
And we have impressive statistics to back up our extensive
experience:• More than 240 international patents issued, including over
150 in the U.S.
• More than 360 international patents pending, including
over 95 in the U.S.
We design and deliver solutions for all your monitoringneeds—including sensors, distributed and rack-based
monitors, software, and supporting services—with thefollowing goals in mind:• Increased availability and production• Lowered maintenance costs• Reduced risk in terms of safety, environmental,
and asset upsets.

2• Over 75,000 3500 Series monitoring systems
installed globally• Over 4 million sensor monitoring points• Over 20 years of offering overspeed detection systems

Want to know more?
Detailed information, including product data sheets andapplication articles and guides, can be found at theHydroelectric Power Generation page of our website.

This system measures the distance between the rotor and stator. Early detectionof air gap anomalies can help operators diagnose rotor-tostator rub and decide
whether to keep the distressed machine online until the next planned outage or
remove it from service before serious damage occurs. Also, long term trendingof gap and shapes can be correlated with operating conditions and used inoperational and rehabilitation planning.

350300 Dynamic Pressure Sensor

The Hydro Dynamic Pressure Sensor uses piezoresistive sensing technology tomeasure both static and dynamic pressures. The sensor uses the 3500/46M Hydro
Monitor and System 1 software to provide static trending and specialized dynamic
plots for diagnostics. This allows the identification and management of vortexing
and cavitation in the turbine and draft tube, and pulsations in the penstock.
The static pressure measurements enable mapping and correlation of these
phenomena across varying head conditions.

3Comprehensive, globally available services

Project Design and Installation
Let our experienced project services team modify and retrofit your existing hydro turbines and generators
for transducers, monitoring systems and condition monitoring software. By supplying services with our
products, you’re assured of getting a high-quality fully engineered and optimized solution tailored to yourspecific requirements. Services include mechanical modification and electrical design drawings, trades
subcontracting and/or oversight, transducer installation, and system configuration and commissioning. You
determine the scope, from best practice recommendations to full turnkey services to anything in between.

Maintenance and Support Agreements
A one-year renewable Maintenance and Support (M&S) Agreement is automatically included with every
product we sell. Its structure consolidates all products installed at your site under a single agreement forease of administration, and entitles you to phone, e-mail, and web-based support from our global network ofexperienced support experts.

Machinery Diagnostic Services
Our more than 70 machinery diagnostic engineers around the world are recognized globally for theirexpertise in gathering and analyzing data to document baseline conditions and troubleshoot even the mostvexing machinery problems.

Remote Monitoring & Diagnostics and Remote Data Hosting
In many cases, traveling to the site to perform machinery diagnostics and assess machinery health isa thing of the past. We can even work with your IT department to engineer remote connectivity solutions thatare fully compliant with your corporate data network requirements.

Supporting Services Agreements
A Supporting Services Agreement (SSA) is a custom-tailored combination of individual remote andsite-based service offerings that addresses the unique needs of your site and your installation. We work withyou as a partner to keep your instrumentation performing optimally at all times and to provide hands-on
assistance that helps you realize the full potential of your condition monitoring system.

Systems for every application
3500 Series machinery
protection system

The 3500 platform has proven its value and dependability
with customers everywhere, year after year. It features
the industry’s most extensive selection of machinery
measurement parameters and utilizes software
configuration for virtually all monitor options, providing
unparalleled flexibility. Using the 3500 System’s monitoring
modules, vibration, bearing temperatures, thrust position,
speed, air gap, process variables (electrical load, oil pressure,reservoir elevation, etc.) and other measurements can be
configured to address the specific needs for correlationof data and analysis of each hydro unit in your facility.
Hydroelectric turbine generators typically operate at low
rotational speeds, usually from 60 to 600 rpm, and are often
physically very large, sometimes with generator rotors that
may be more than 50 feet in diameter and weigh more than
1,000 tons. Their physical mass and slow rotational speeds
give rise to large vibration amplitudes and low vibration
frequencies. This requires monitoring capabilities with special
low-frequency response, filtering, and signal conditioning.

The 3500/46M Hydro Monitor module has
been specifically developed to deliver thesecapabilities by providing the suite of radialvibration measurements used for guide bearing
runout and seal ring position, and generator
air gap measurements. The 3500/46M Hydro
Monitor provides:• Overall vibration (direct)• 1X filtered vibration and phase• NX filtered vibration and phase (where N is auser-selectable integer between 2 and 20)• NOT 1X vibration amplitude• Gap voltage (shaft radial position)• Composite (shear pin failure indication)• Instantaneous air gap• Average air gap• Minimum air gap• Maximum air gap• Minimum air gap pole number• Maximum air gap pole number
The 3500/46M Hydro Monitor module provides users with up
to eight configurable machine states for which independent
alarm setpoints and time delays can be programmed.
This supports a parametric monitoring strategy tailored tothe individual operating modes of your hydro assets. The
multi‑mode feature works in concert with the State‑Based
Analysis option of our System 1 software.

Training
We provide in-depth technical training that is routinely praised by customers for its highly effective “learn
by doing” labs coupled with classroom-style instruction. A comprehensive suite of product training courses
is augmented by courses that teach the fundamentals of rotating machinery behavior and diagnostic
techniques. Our courses can be provided at any of our global training centers or at your site.

Cybersecurity Services
We offer a comprehensive suite of Cyber Security Services, including: Cyber Asset Risk Assessments forcompliance with industry standards; systems hardening that provides centralized security management andserver health monitoring; security recommendations regarding network configurations, physical security, andchange management.

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System 1 software
Hydro turbine-generator plants present unique dataacquisition and analysis challenges due to machine design,
low rotational frequency, operating mode-specific dynamic
behaviour, and failure mode characteristics common tothese asset types. Bently Nevada’s System 1 optimization anddiagnostic software platform incorporates hydro-specificfunctionality, designed to dramatically improve your ability
to proactively manage these units. Its exceptional data
integration, analytic and diagnostic capabilities enableengineering and maintenance personnel to spend less time
searching for problems and more time proactively managing
and maintaining your most critical production assets. System
1 software also supports integration of process data from thediverse information systems throughout your plant, providing
a common platform for data correlation, analysis andviewing. Packages designed specifically for hydro turbinesand generators are available.

created in an intuitive GUI interface. Analytics operate on live
data in real-time, enabling fast identification and notificationof detected problems.

Software lifecycle support

System 1 software is continually developed and enhanced
to imbed new functionality, maintain compatibility withinterfaces and operating systems, and to incorporate thevaluable feedback from our active end-users. Updates are
released biannually, accessible to all users with a current
Support Agreement.

Hydro-specific plot types

In addition to the comprehensive set of standard plot types1,
System 1 software provides the following plots specificallydesigned for diagnosing/analyzing hydro turbine-generator
anomalies.

Hydro-specific condition monitoringand diagnostics

The Bently Nevada Hydro Turbine/Generator online
management and diagnostics software package is designed
to work with the Bently Nevada 3500 online monitoring
system, collecting both static and dynamic high-resolution
data including: vibration, partial discharge, air gap, position,
speed, temperature, and more. This package can help you
reduce operational risk caused by partial load and frequent
cycling, improve asset reliability and productivity, and reduce
maintenance costs.

Designed for multiple operating states

Machines that rotate bi-directionally (pumped storage
units), or which routinely operate under differing hydraulicor load conditions, need a simple and robust method to
identify and segregate the various operating modes for bothprotection and analysis. The Bently Nevada 3500/46M Hydro
monitor supports multi-mode operation, allowing separate
alarm setpoints to be defined for up to eight different
operating modes. Within System 1, operating modes canbe further defined with rule logic using any combination ofavailable data, to enable accurate assessment of machinecondition and change under consistent operating conditions.

Hydro Asset
Health HMI
Dashboard
View

The System 1 interface uses a rich graphical information
screen layout to provide detailed machinery context
of key operating information, alarm or fault status, andasset management performance indicators. This is ahighly flexible and intuitive environment, configurable
for a plantwide overview or detailed asset summary,enhancing the accessibility of machinery health datato all users. The navigable icons and data fields arecolor‑coded according to alarm status, supporting drill
down directly to diagnostic data formats.

Air Gap Plots

Displays the rotor poles versus the air gap for a single
channel or the rotor poles versus the minimum air gap
on all channels. Variables available include Average,
Instantaneous, Max & Min Air Gap, and Max & Min Pole
number.

Rotor Stator
Plots

A multiple channel plot set showing the Stator Shaperelative to the rotor shape, and the Rotor Shape andor Stator shape from one or more sensors or from theaverage of all sensors. These plots are derived fromgenerator Air Gap measurements.

X versus Y

Plotting any X (such as vibration) versus any Y (such asunit load), provides powerful diagnostic tools. Causeand-effect relationships and correlation can be easily
visualized and understood. System 1 software has data
historian capabilities allowing it to archive virtually any
data, even if not condition-related. It can also interface toexisting historian systems you may already have installed.

Performance
Map Plot

Enhanced X versus Y plot displays a current value
relative to multiple user-configurable characteristic
curves which may represent, for example, unit operating
limits or regions of undesirable operation. The overlay
reference curve sets can be easily customized torepresent clearance boundaries, in the case of shaft
position plot formats, for example.

MultiParameter
Plots

Multiple parameters can be displayed on the same plot.
For example, plotting turbine flow, combined unit load,
and bearing vibration provides the ability to immediately
identify events associated with rough load zone. Changes
in the duration and amplitude of these events can be anindication of excessive wear or impending failure.

Real-time analytic tools

Each deployment includes the System 1 Decision Support
analytics environment, allowing any user to configure data
evaluation rule logic so that proven knowledge and bestpractices can be applied and shared across a business in a
repeatable and manageable process. Simple comparison
logic, or complex mathematical operations, including
spectral band extractions and array operations, can be
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Vibration data can be displayed by System 1 software in the following standard plot
types: Orbit, Timebase, Polar, Bode, Shaft Centerline, Cascade, Waterfall, Spectrum,
Trend, Bargraph, and Tabular list.
1

System 1’s asset health dashboard
identifies any areas that require further
attention and embedded links allow
users to move easily to the underlying
data and diagnostics plots for problem
spots for further analysis.
Any number of HMI screens can becreated, typically featuring an initiallanding page with plant-wide overview
displaying key performance indicatorsfor machine health and reliability.
The drill-down pages reveal detail for
major plant subsystems, including
lubrication systems, generator cooling,
generator electrical and mechanicalmonitoring, and turbine mechanicalmonitoring.
The System 1 HMI screens are intended
to be intuitive and accessible toexperienced and novice users alike,with imbedded navigation buttons, andcolor-coding to reflect the severity ofany detected anomaly.

Hydro condition measurements
1.

Generator Partial Discharge

Partial discharges are low-level electrical discharges that
occur within the voids of high voltage insulation systems.
By monitoring these partial discharges, a variety of winding
related problems can be detected, allowing maintenance tobe planned and serious failures to be avoided.

7.

• Continuous PD Monitor• Capacitive PD Couplers

2.

• 4000 Series Air Gap Sensors

8.

• 3500/46M Hydro Monitor• 330505 Low-Frequency Seismic Sensor, Velomitor or
Velomitor CT• Orbit 60 Monitoring System

3.

1

7

2

8
3

Thrust Bearing Oil Film Thickness/Rotor Position

An absence or reduction in oil film thickness at the thrustpads results in rapid breakdown of the bearing babbit andcan result in rotor/bearing damage if not corrected. On hydrounits, the thrust bearing shoes are fitted with proximity probes
observing the thrust collar, providing a measurement of oil
film thickness.
• 3500/46M or 3500/45 Position Monitor

9• 3300 XL Series Proximity Transducer• Orbit 60 Monitoring System

4.
4

5

Keyphasor* Signal

A proximity probe observing a once-per-turn notch or
protrusion on the machine’s shaft provides a precise reference
signal used for indicating rotational speed, filtering vibration
to multiples of running speed (such as 1X, NX, and NOT 1X),
providing vibration phase information and allowing air gap
profile data, rotor pole temperatures, etc. Two probes anda 3500/50 tachometer can provide direction of rotation
detection. The Keyphasor signal is required for synchronous
values and sampling in the 3500/46M and 3701/46 monitors.
• 3500/50M Tachometer or 3500/25 Keyphasor Module

9• 3300 XL Series Proximity Transducer• Orbit 60 Monitoring System

5.
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10

Rotor Vibration and Position

Detects a variety of important malfunctions such as roughload zone, various sources of unbalance, shear pin failure,
bearing problems, and wicket gate problems. Each channel ofthe 3500/46M module can simultaneously monitor direct, 1X
vector, NX vector, NOT 1X, shaft radial position (gap voltage),and composite amplitude (gap voltage change multiplied by
NX amplitude).
• 3500/46M Hydro Monitor• 3300 XL Series Proximity Transducer

6• Orbit 60 Monitoring System

6.

Head Cover/Draft Tube Vibration and
Dynamic Pressure

Air gap measurement is important because the stator is a
flexible assembly that can become non-concentric and/or
out of round. The monitor is able to provide instantaneous,minimum, maximum, and average air gap measurements
along with the rotor pole to which min and max measurements
coincide. Connecting to the System 1* software enables
interpolation between sensors, providing calculated stator
shape plots.
• 3500/46M Hydro Monitor

Stator Frame Vibration

Vibrations of the stator core can increase after many
temperature cycles, resulting in loose stator components. By
mounting an appropriate seismic vibration transducer on thestator core/frame, such problems can be detected before
serious damage occurs.

Generator Air Gap

Generator Temperatures

Temperature sensors installed in locations such as in statorslots, air cooler inlet and outlet, water inlet and outlet rotor
poles, etc., provide important information on generator
condition. The monitor provides alarming functions, alerting
operators when temperatures are outside of acceptable
limits. The monitor can also supply temperature information
to System 1 software where it can be trended and correlatedwith other measurements for a more complete picture ofunit health.
• 3500/60, /61, or /65 Temperature Monitor• RTD or Thermocouple• Orbit 60 Monitoring System

9.

Thrust and Guide Bearing Temperatures

Bearing temperature can indicate problems related to
fluid-film bearings, including overload, bearing fatigue, orinsufficient lubrication.
• 3500/60, /61, or /65 Temperature Monitor• RTD or Thermocouple• Orbit 60 Monitoring System

10. Seal Ring Condition/Blade Tip Clearance

Francis turbines employ seal rings to prevent unwanted
leakage of water past the runner, influencing efficiency. Kaplan
and propeller type turbines experience changes in blade tip
clearances or chamber deformation. Transducers mounted
to observe/monitor these clearances can detect problems as
they develop.
• 3500/46M Hydro Monitor• 3300 XL Series 11 mm underwater Proximity Transducer• Orbit 60 Monitoring System

Process and Environmental Variables

Load, reactive load, exciter voltage and current, generator
voltage and current, lube oil pressure, wicket gate position, andreservoir elevation are just a few of the parameters that may
be available in the unit’s or plant’s control and automation
system. These variables are often correlated with the condition
monitoring measurements for enhancing the diagnostic
capabilities of the system. If these variables cannot be
imported directly into the condition monitoring software, they
can be obtained via the 3500 System.
• 3500/62 Process Variable Monitor• Orbit 60 Monitoring System• System 1 OPC UA and/or Modbus data import

Cavitation can damage the turbine, eroding metal, affecting
efficiency, and eventually forcing a shutdown and dewatering
for repair of affected parts. Improper clearances can cause
vibration of the head cover. By monitoring the draft tube orhead cover with accelerometers and/or dynamic pressure
sensors, these conditions can be detected and adjustments
made to avoid operating in undesirable regions.
• 3500/46M Hydro or 3500/42M Proximitor*/Seismic Monitor• 330425/330400 Accelerometer• Orbit 60 Monitoring System• 350300 Dynamic Pressure Sensor
89Operating hydro inchallenging conditions
Hydro turbines are facing a broader set of operating
conditions that increase the risk and wear. System operators
would base load these units, only reducing load or removing
the units from service when maintenance was required, thepower was not needed, or stream flow conditions dictated. In
this base-load mode, a typical hydro machine could operate
successfully for over 40 years with only routine scheduled
maintenance and minimal condition monitoring.
In today’s world of partially deregulated utilities and grid
systems where fish and water issues often eclipse energy
issues, the operating flexibility of hydro machines has often ledthem to be load-follow units with continuous load changes
and partial-load operation. Running a unit at partial loadbrings into play considerations like rough load zone andcavitation, along with operation that is far from the unit’s peakefficiency. Further, continuous load cycling introduces thermal,
mechanical, and electrical stresses on the machinery that
may not have even been considered in the original design.
In some cases, such machines are cycled on- and off-line
multiple times per day. And pumped storage applications canexperience even more starts and stops, often representing
the most extreme operating conditions of all hydro units. At
the same time, normal scheduled maintenance outages

The business caseare being reduced or eliminated. The circumstances thatonce resulted in virtually trouble-free operation for decades
simply don’t apply any more. Clearly, the need for condition
monitoring on hydro units has never been more important.
For over six decades, the Bently Nevada condition monitoring
portfolio has been synonymous with the highest quality, mostreliable choice available for critical machinery. With a namethat is trusted worldwide for machinery protection, over four
million transducers and monitoring channels have been
installed around the globe. Our comprehensive selection ofhydro-specific transducers, monitors, diagnostic software,and of course, services, has been designed with the uniqueneeds of hydro operators in mind.

Benefits• Lower life-cycle costs• Improved efficiency• Avoidance of load zones
with damaging vibrationor cavitation conditions• Early warning ofimpending failures• Proactive maintenanceplanning and intervention• Reduced maintenancecosts• Increased availability
and reliability• Longer intervals between
outages• Lower insurance premiums

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Machinery protection and asset condition monitoring
systems are an investment that pays back quickly andin numerous ways. Today, such systems have moved
from simply “good engineering practice” to “goodbusiness practice” in hydro power generation as well as
many other industries. These systems have proven andcontinue to prove their value time and again.

Payback through Protection

Our solutions help protect your machinery fromcatastrophic failures and their costs.
For more than 60 years, the Bently Nevada
name has been recognized for its industry
leadership in machinery protection andcondition monitoring. Today, with morethan one million channels of machinery protection
installed worldwide, customers have made us the provenchoice for machine protection. We not only protect yourmachinery, but our legendary product quality, deep
application expertise, and highly competent locallyavailable service help protect your condition monitoring
investment as well.

Payback through Mechanical Validation

Our solutions let you capture baseline machinery
conditions, pre- and post‑maintenance, giving you areference for optimal decision making.
One of the most crucial times in the life of amachine is immediately after maintenancehas been performed. We can tell you if“all is well” with systems that capture
relevant data both before and after maintenance. You
can instantly see if problems are present and makedecisions accordingly. For many customers, the ability
to knowledgeably continue with or abort the startup of ahydro turbine-generator unit can more than pay for their
entire system in a single event.

Payback through Asset
Performance Management (APM)

Our solutions provide the data necessary to optimize
machinery operations and maintenance for financial
and market conditions.
Hydro power assets are increasingly asked
to compensate for the effects of a morediverse mix of generating assets, which
often forces them into operating regimesthat cause increased machine stress and wear. As
industry digitizes to more effectively monitor, monetize,and optimize its assets, the ability to incorporate richasset health data from a condition monitoring system
becomes essential for accurate analysis and decisions.

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Copyright 2023 Baker Hughes Company. This material contains one or more registeredtrademarks of Baker Hughes Company and its subsidiaries in one or more countries. All
third-party product and company names are trademarks of their respective holders.
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