NSK Bruel & Kjaer Vibro VC-8000 Operation And Maintenance

Hydro and low speed machines including machine-state alarming

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Instruction

VC-8000 for Hydro

and Low Speed Machines

Including Machine-State Alarming

Operation and Maintenance

UNRESTRICTED DOCUMENT

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Page 1 Instruction VC-8000 for Hydro and Low Speed Machines Including Machine-State Alarming Operation and Maintenance UNRESTRICTED DOCUMENT...
Page 2 Trademarks and Copyrights All trademarks, service marks, and/or registered trademarks used in this document belong to BK Vibro America Inc., except as noted below: Copyright © 2021 Brüel & Kjær Vibro GmbH All rights to this technical documentation remain reserved. Any corporeal or incorporeal reproduction or dissemination of this technical documentation or making this document available to the public without prior written approval from Brüel &...
Page 3: Table Of Contents
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Table of Contents Table of Contents Overview ........................6 Vertical Machines..........................6 1.1.1 Sensor Orientation & Direction of Rotation ......................6 Hydro Radial Vibration .................... 7 Configure Hydro Radial Vibration ....................... 7 2.1.1 Rack Layout ................................
Page 4 Selecting a Seismic Sensor .................. 20 Machine Speed ............................ 20 Hydro Measurements ......................... 20 Environment (Noise) ........................... 21 System Specifications ........................22 6.4.1 Channel Type Selection ............................22 6.4.2 Sensor Specifications ............................24 6.4.3 SETPOINT CMS Plots and Measurement Units ....................25 Cost ..............................
Page 5 Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Table of Contents Machine-State Alarming ..................43 Configure VC-8000 Channels ......................43 8.1.1 Phase Trigger (Speed) Channel ........................... 43 8.1.2 Discrete Input Channel ............................43 8.1.3 Define Machine (Asset) Groups ........................... 44 8.1.4 Temperature Channels (TMM) ..........................
Page 6: Overview
Overview This application note is an addendum to the VC-8000 Operation & Maintenance Manual (S1079330), and the SETPOINT Condition Monitoring System Operation Manual (S1176125). Please refer to these manuals for basic operating instructions. This application note provides information specific for hydro turbine generators, other low speed machines, and machines using Machine-State alarming.
Page 7: Hydro Radial Vibration
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Hydro Radial Vibration Hydro Radial Vibration The Hydro Radial Vibration channel is optimized for low speed (< 720 RPM) and provides a selection of tracking filters and bandpass filters. Table 2-1 Hydro Radial Vibration Measurement Description...
Page 8: Verify Hydro Radial Vibration
Verify Hydro Radial Vibration Set up the test equipment as shown. Set the power supply to the transducer Gap voltage. Figure 2-1) Test Setup for Hydro Radial Vibration Set the function generator to a frequency inside your band-pass filtered region (i.e. 10 Hz) so the filter does not attenuate the signal.
Page 9: Hydro Velocity
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Hydro Velocity Hydro Velocity The Hydro Velocity channel is specifically designed for Hydro machines. It provides a good selection of tracking filters (1X, 2X) and bandpass filters to be used depending on the installed location of the sensor.
Page 10: Verify Hydro Velocity
Verify Hydro Velocity 3.2.1 Test Setup Simulate the Hydro Velocity channel depending on the sensor selected. 3.2.1.1 Constant Current Velocity Sensor Use a 3.3 kΩ resistor to set the bias voltage (+10 Vdc). The 940 µF (or larger) capacitor is used to force the current through the resistor.
Page 11: Simulate Signals (Standard - In/S)
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Hydro Velocity 3.2.2 Simulate Signals (Standard - in/s) Use a test frequency compatible with the Hydro Velocity Channel (i.e. 25 Hz). Use the following equations to calculate the velocity input value: Equation 3.1 (in/s pk) ��...
Page 12: Simulate Signals (Standard - Mm/S)
3.2.3 Simulate Signals (Standard - mm/s) Use a test frequency compatible with the Hydro Velocity Channel (i.e. 25 Hz). Use the following equations to calculate the velocity input value: Equation 3.3 (mm/s pk) �� ( �� ( �� ) = ∗...
Page 13: Simulate Signals (Integrated - Mils Pp)
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Hydro Velocity Simulate Signals (Integrated – mils pp) 3.2.4 Use a test frequency compatible with the Hydro Velocity Channel (i.e. 25 Hz). Use the following equations to calculate the velocity input value: Equation 3.5 (mils pp) ��...
Page 14: Low F Velocity
Low F Velocity The Low F Velocity was not designed for Hydro monitoring. It is a modification of the Standard Velocity channel with some improvements for lower frequency measurements. The band-pass frequency of the channel is very wide. The integration of a signal (with low frequency and a wide band-pass) requires extra processor power;...
Page 15: Low F Acceleration
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Low F Acceleration Low F Acceleration The Low F Acceleration channel can be used for Hydro monitoring, but it was not specifically designed for Hydro monitoring. It is a modification of the Standard Acceleration channel with some improvements for lower frequency signal components.
Page 16: Configure Low F Acceleration
Configure Low F Acceleration If you are using this channel for a Hydro machine, you a will probably need to modify a few of the default channel settings. These are explained below. 5.1.1 Setting the Low Pass Filter To set the Low Pass filter correctly, you need to know what you are measuring. The default Low Pass filter is 200 Hz.
Page 17: Verify Low F Acceleration
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Low F Acceleration Verify Low F Acceleration 5.2.1 Test Setup Use a 3.3 kΩ resistor to set the bias voltage (+10 Vdc). The 940 µF (or larger) capacitor is used to force the current through the resistor.
Page 18: Simulate Signals (Integrated - In/S)
Simulate Signals (Integrated – in/s) 5.2.3 Use a test frequency compatible with the configuration of the channel (i.e. 25 Hz). Use the following equations to calculate the acceleration input value: Equation 5.3 (in/s pk) �� ( ��) ∗ �� (��) ��...
Page 19: Simulate Signals (Integrated - Mm/S)
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Low F Acceleration Simulate Signals (Integrated – mm/s) 5.2.4 Use a test frequency compatible with the configuration of the channel (i.e. 25 Hz). Use the following equations to calculate the acceleration input value: Equation 5.5 (mm/s pk) ��...
Page 20: Selecting A Seismic Sensor
Selecting a Seismic Sensor There are several things to consider before selecting a sensor. 1. What is the speed of the machine? 2. What am I trying to measure? 3. What is the environment? 4. What are the specifications for the system (Sensor, VC-8000, CMS) 5.
Page 21: Environment (Noise)
Selecting a Seismic Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Sensor Protection or Condition Monitoring If the measurement is purely for condition monitoring (and not to protect the machine) than it may be acceptable to choose an accelerometer to reduce cost if the customer understands the trade-offs involved.
Page 22: System Specifications
System Specifications Sensor selection impacts the channel types that can be used in VC-8000. This, in turn, impacts what can be viewed in SETPOINT CMS software. The following sections explore these relationships. 6.4.1 Channel Type Selection If you select to use an Accelerometer on a low speed machine, you must use one of the acceleration channels.
Page 23 Selecting a Seismic Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Sensor 6.4.1.1 Band-pass Filters The Channel Type you select will affect the band-pass filter options that are available to you. The Direct measurement of each channel is band-pass filtered (see Table 6-2). Protection systems use band-pass filters on the Direct measurement to improve the integrity of the signal that is (normally) used to trip the machine.
Page 24: Sensor Specifications
6.4.1.2 Filter Steepness The Channel Type you select determines the steepness of the filter. A steeper filter provides a stronger signal near the corner frequencies and it also does a better job of removing low frequency noise. The Hydro velocity channel has the steepest filters (14 pole); Table 6-3 Comparison of filter steepness (poles) Channel Type High Pass...
Page 25: Setpoint Cms Plots And Measurement Units
Selecting a Seismic Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Sensor 6.4.2.1 VS-068 and VS-069 - Limitations B&K Vibro VS-068 and VS-069 should not be used with VC-8000 and SETPOINT CMS software for applications below 10 Hz (600 CPM) – unless the CMS waveforms are disabled. Below 10 Hz, the VC-8000 provides linearization for the overall value of the signal;...
Page 26: Hydro Air Gap Channel
Hydro Air Gap Channel The Hydro Air Gap channel uses capacitive displacement sensors to assist in detecting generator faults such as dislocation of poles, loose rotor rims, deformed rim or center-line offset. The channel provides the following measurements: Table 7-1 Hydro Air Gap channel – Measurements Measurement Description Minimum Air Gap...
Page 27: Background
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Hydro Air Gap Channel Background There are several potential failure modes that are related to the physical configuration of hydro generators. Hydro units turn at relatively low speeds to extract maximum energy from the water head. This means many rotor poles are needed to generate electricity at line frequency, which results in generators having a large diameter with a small space between the stator and rotor (air gap).
Page 28: How Many Sensors To Install
7.2.2 How Many Sensors to Install The air gap sensor measures the distance from the stator to each generator pole as it passes by. One sensor can only measure the distance at one location – where it is installed. Because the stator can deform in an irregular pattern, it is common to install multiple sensors;...
Page 29: Configure Hydro Air Gap
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Hydro Air Gap Channel Configure Hydro Air Gap 7.3.1 Rack Layout The Hydro Air Gap channels can be installed in any UMM channel in the rack (they are not XY pairs). However, there are some trade-offs to consider.
Page 30 Instruction Picture Add and configure a hydro generator. Name Assign a unique name to identify the hydro generator. This field is used in SETPOINT CMS software. Poles The number of generator poles. The VC-8000 uses this number to count the poles and determine the Minimum Air Gap per one revolution.
Page 31: Phase Trigger
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Hydro Air Gap Channel Instruction Picture Sensor Gap (A) and When the machine is stopped measure the following: Sensor Gap (A) is the physical distance between the Sensor Voltage (B) sensor face and the pole in front of that sensor.
Page 32: Waveform Sample Rates
7.3.4 Waveform Sample Rates The Air Gap channel waveforms are used in the SETPOINT CMS software. They are not used for machinery protection. Figure 7-3) Waveform Data Collection Best practice is to collect a waveform over 2 (or 4) revolutions with at least 10 samples per pole. Asynchronous Waveform (Example) Start by selecting the number of samples (See Figure 7-3).
Page 33: Compatible Sensors
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Hydro Air Gap Channel If the minimum air gap measurement (24 hours) varies from 21.2 mm to 20.9 mm (Delta 0.3 mm) then a suggested I-Factor would be 0.3 x 1.5 = 0.45 mm (amplitude change). Next you must calculate the percentage change.
Page 34: Setting Ok Limits
IMPORTANT Capacitive air gap sensors require more current than can be supplied by the UMM. Supply the power for the air gap sensors using an external power supply. 7.4.2 Setting Ok Limits If the Air Gap sensor has a range of 0 to +10 Vdc, set the Lower Ok Limit to 100 mV; This will detect an open circuit (0 V) or a sensor with no power (0 V).
Page 35: Verify Air Gap Alarms
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Hydro Air Gap Channel Verify Air Gap Alarms Simulate the Air Gap channel using a function generator (A) and a DC power supply (B) as shown in Figure 7-5 The Minimum Air Gap measurement is calculated from the lower portion of the square wave (sensor viewing the pole);...
Page 36 Example: Test an Air Gap channel with an Alert alarm • Sensor Gap (sensor face to rotor pole) = 35 mm • Sensor Gap (sensor face to rotor pole) Volts = 6.0 V • Sensor Offset Distance = 5 mm •...
Page 37: Setpoint Cms Air Gap Plots
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Hydro Air Gap Channel SETPOINT CMS Air Gap Plots The VC-8000 Air Gap channel provides a Rotor Profile waveform and an Asynchronous waveform to the SETPOINT CMS software. This data is used for the Asynchronous Timebase plot (A), the Rotor Profile Timebase plot (B), and the Air Gap plot (C) (see Figure 7-7).
Page 38: Creating Multiple Air Gap Plots
7.6.1 Creating Multiple Air Gap Plots Air Gap channels with the same CMS Navigation path are displayed on the same Air Gap plot. To place channels on separate plots, make the CMS Navigation path different for each channel (or group of channels). For example, if you have sensors on the upper and lower side of the generator, use a CMS Navigation path of “Unit 1\Upper”, for the upper channels, and “Unit 1\Lower”...
Page 39 Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Hydro Air Gap Channel Example: Simulate an Air Gap channel with a Minimum Air Gap of 30 mm. The settings described here, are for convenience to make it easier to simulate the channel. Air Gap Channel •...
Page 40 Instruction Picture Set the Trend manual scale to 0-40 mm Set the Air Gap manual scale to 0-80 mm Note: The Air Gap scale is increased to 80mm to make it easier to view the Air Gap plot. The Air Gap plot is shown here. Due to variations in the timing between the function generators your plot may appear slightly different.
Page 41 Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Hydro Air Gap Channel Instruction Picture On the Plot tab (Orbit/Timebase section) Select to show the Asynch Orbit/Timebase Set Asynch Orbit/Timebase = 0.4 seconds. This controls how much of the Asynch waveform is shown.
Page 42: Troubleshooting The Air Gap Plot
7.6.4 Troubleshooting the Air Gap Plot If the rotor profile waveform is not being shown in the CMS software: • Check the status bar (A) of the Air Gap channel using the VC-8000 Maintenance software. Verify the status is OK (see Figure 7-10). •...
Page 43: Machine-State Alarming
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Machine-State Alarming Machine-State Alarming Machine-State Alarming allows alert and danger alarm levels to change, based on the operational state of the machine (i.e. Pump/Storage Hydro units). One alarm level is set when the machine is generating electricity (Machine-State A (Generating)), and another alarm level is used when the machine is pumping water back into the upper reservoir (Machine-State B (Pumping)).
Page 44: Define Machine (Asset) Groups
3. The fields Contact Function, and Group Name (see Figure 8-2) are not used for machine-state logic. These fields are for Bypass, Inhibit, and Trip Multiply control functions and are rarely used (See the VC-8000 instruction manual for more information). Figure 8-2) Set Polarity 4.
Page 45: Temperature Channels (Tmm)
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Machine-State Alarming 8.1.4 Temperature Channels (TMM) The TMM does not have the ability to do machine-state alarming. If temperature is needed for machine-state alarming, the user must bring the temperatures into a UMM Process Variable channel using a transmitter (i.e.
Page 46: Configure Machine-States
Configure Machine-States The machine-states, and logic are configured on the Channels tab, States view. Your basic rack configuration (channel names, channel types, and rack layout) should be completed before you configure machine-state logic. 8.2.1 Add a Machine Follow these steps to add Machines for your machine-state logic (see Figure 8-6). 1.
Page 47: Add Inputs
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Machine-State Alarming 8.2.2 Add Inputs Follow these steps to add Inputs for your machine-state logic (see Figure 8-7). 1. Select the Machine (row). The Input will be added to this machine. 2.
Page 48: Add States
8.2.3 Add States Follow these steps to add States for your machine-state logic (see Figure 8-8). 1. Select the Machine (row). The State will be added for this machine. 2. Select Add, State from the menu. A new State will be shown in the States grid. Repeat this step to add an additional state.
Page 49: Set Machine-State Definitions
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Machine-State Alarming 8.2.4 Set Machine-State Definitions Follow these steps to define the states for your machine-state logic (see Figure 8-9). 1. Select the machine. 2. Notice the definition type. 3.
Page 50: Configure Machine-State Alarms
When the Phase Trigger becomes valid (see Figure 8-10), a speed reference is saved, and the machine-state equals Steady State (A). The speed is then checked every 40 msec. When the speed increases by the Delta RPM setting (Phase Trigger channel) the machine-state changes to Accelerating (B).
Page 51: Validate Machine-State Alarming
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Machine-State Alarming Figure 8-11) Machine-state Alarms The Alarm Type can be Disabled, In Band, Out of Band, Over, or Under. The Alarm Type and Alarm Time Delay must be the same for all machine-states. Notice in Figure 8-11 that the Generating and Pumping state alarms can be disabled individually;...
Page 52: Documentation
• Place Unit 1 in the Default state (if applicable) • Verify the machine-state by viewing the Maintenance software, or the machine-state Modbus register. • Repeat the Alert/Danger channel tests for the Default state. 8.4.1 Documentation For documentation of the machine-state validation, you can copy and paste the machine-state alarms from the VC-8000 Setup software into a spreadsheet.
Page 53: Alarm Delays (Timers) And Hysteresis
Brüel & Kjær Vibro │Instruction VC-8000 for Hydro and Low Speed Machines Machine-State Alarming 8.4.3 Alarm Delays (Timers) and Hysteresis Alarm Delays (Timers) are not reset when switching between states. When the current input exceeds the current alarm setting, the Alarm Delay timer starts. If a new machine-state is triggered the timer will stop - if the input is less than the new alarm setting;...
Page 54 Contact Brüel & Kjær Vibro GmbH Brüel & Kjær Vibro A/S BK Vibro America Inc. Leydheckerstrasse 10 Lyngby Hovedgade 94, 5 sal 1100 Mark Circle 64293 Darmstadt 2800 Lyngby Gardnerville NV 89410 Germany Denmark Phone: +49 6151 428 0 Phone: +45 69 89 03 00 Phone: +1 (775) 552 3110...