Vibration Monitoring for the Wind Industry
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Introduction
Vibration monitoring for the wind industry is a critical cost-saving and safety measure. Wind turbines consist of many rotating elements, which are subject to wear and tear over time due to constant variation in speed and load.
Common faults include:
- Bearing failures
- Gear wear and tear
- Blad vibration
- Electrical problems
- Imbalance
- Misalignment
- Looseness
- Resonance
Thees faults have tremendous replacement costs due to the large size and weight of turbine components. Predictive maintenance can be used to improve reliability, lower replacement costs, and help ensure human safety.
What We Offer
At CTC, we specialize in providing the highest-quality industrial accelerometers specifically designed to meet the needs of the wind industry. Our products enable effective monitoring of: main bearings, generators, and gearboxes used in wind turbines. We offer general purpose, triaxial, low frequency, and molded accelerometers, as well as all related cables, connectors, and mounting hardware.
General Purpose Accelerometers
For gearbox and generator applications, CTC general purpose accelerometers are recommended. This is because the intermediate shaft and output shaft of the gearbox will have higher rotational speeds and generate a higher frequency disturbance relative to the bearings and gear mesh. The output of the gearbox typically rotates 50 - 60 times faster than the input shaft.
As a result of these increased rotational speeds, CTC general purpose accelerometers can be used. CTC's AC102 Series top exit sensors provide a 100 mV/g output over the range of 0.5 - 13,500 Hz (30 - 810,000 CPM) ±3 dB, and AC104 side exit Series sensors provide a 100 mV/g output over the range of 0.5 - 10,000 Hz (30 - 600,000 CPM) ±3 dB. CTC recommends CB102-A2A cable and connector assembly for use with AC102-1A and AC104-1A. This cable assembly can be fully customized to your desired length.
AC102-1A General Purpose Accelerometer, Top Exit 2 Pin Connector, 100 mV/g, ±10%
AC104-1A General Purpose Accelerometer, Side Exit 2 Pin Connector, 100 mV/g, ±10%
CB102 Twisted, Shielded Pair Cable with Red FEP Jacket and A2A Polycarbonate Molded, 2 Socket MIL-Style Connector for Permanent Mounting
TREA Series Triaxial Accelerometers
If triaxial configurations are desired, CTC's TREA330 and TREA331 miniature triaxial accelerometers are the ideal solution for turbine monitoring. These sensors feature a low profile form factor, 100 mV/g output, and are capable of measuring from 0.5 - 15,000 Hz (30 - 900,000 CPM) within a ±3 dB tolerance. CTC recommends CB119-J4A cable and connector assembly which can be fully customized to your desired length.
TREA330 Premium Miniature Industrial Triaxial Accelerometer, Side Exit 4 Pin Mini-MIL Connector, 100 mV/g, ±5%
TREA331 Low Cost Miniature Industrial Accelerometer, Side Exit 4 Pin Mini-MIL Connector, 100 mV/g, ±15%
CB119 4 Conductor, Shielded Cable with Orange FEP Jacket and J4A Polycarbonate Molded, 4 Socket Mini-MIL Connector for Permanent Mounting
Low Frequency Accelerometers
For low speed applications like main bearings, CTC recommends our AC133-1A and AC134-1A 500 mV/g low frequency accelerometers. The larger mV/g output gives the sensor sufficient voltages signals, which will improve its ability to read low amplitude vibration signals down to 0.1 Hz within a ± 3 dB sensitivity tolerance. AC133 and AC134 accelerometers have a frequency response of 0.1 to 10,000 Hz (6 - 600,000 CPM) within a ±3 dB tolerance which provides the ability to monitor low frequency and low amplitude vibration levels. These accelerometers are specifically designed to enable pure low-frequency measurements and use high-frequency detection and analysis techniques all in one hermetically sealed accelerometer.
AC133-1A Low Frequency Accelerometer, Top Exit 2 Pin Connector, 500 mV/g, ±10%
AC134-1A Low Frequency Accelerometer, Side Exit 2 Pin Connector, 500 mV/g, ±10%
MA Series Molded Sensors
CTC's MA Series molded sensors offer high-voltage isolation and are ideal for use in wind turbine monitoring applications in areas that are prone to lightening strikes. These molded sensors feature a durable stainless steel base and connector, with a polycarbonate-overmolded body. They offer 10 kV DC (7 kV AC) electrical isolation between the base and the electronics. Our MA Series sensors come in both 100 mV/g and 500 mV/g options.
Available configurations include:
100 mV/g Top Exit Molded Sensors
MA150 - ± 15% | MA102 - ± 10% | MA202 - ± 5%
500 mV/g Top Exit Molded Sensors
MA153 - ± 15% | MA133 - ± 10% | MA233 - ± 5%
CTC recommends using MA Series sensors with A2AG and A2NG grounded connectors for additional noise protection:
CB102-A2AG Red FEP Jacketed, Twisted, Shielded Pair Cable and Two-Socket MIL-Style Polycarbonate Molded, Grounded Connector
Mounting Hardware
Due to the main bearing, gearbox, and generator being located between 50 and 150 meters in the air, accelerometers should be permanently stud mounted. CTC Offers a variety of studs, as well as installation tool kits for the mounting surface to be spot faced, drilled, and tapped for threaded attachment of the accelerometer to the machine.
