Summary of Contents for Datawell BV Wave Unit
- Page 1 Wave Unit Reference Manual Service & Sales Voltastraat 3 1704 RP Heerhugowaard The Netherlands +31 72 534 5298 +31 72 572 6406 April 15, 2019 www.datawell.nl...
- Page 4 Declares under sole responsibility that the product: Product name: Waverider Trade name: Datawell Model: Wave Unit complies with the essential requirements of the following applicable European Directives, and carries the CE marking accordingly: EMC Directive (2004/108/EC) RoHS Directive (2011/65/EU) and conforms with the following product standards:...
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Page 5: Table Of Contents
2.1.1 Bags of drying agent ................. 9 2.2 Inspection ....................9 2.2.1 Damage .................... 9 2.2.2 Opening the Wave Unit and sealing rings ......... 9 2.3 Service ..................... 9 2.3.1 The Wave Unit’s wave motion sensor ..........9 3 Trouble Shooting ..................11 3.1 Wave Unit diagnosis ................ - Page 6 5.5.1 Wave Unit serial message format ........... 27 5.5.2 Datawell real-time format ..............28 5.6 Stainless steel housing and lid assembly ..........31 5.6.1 Installation ..................31 5.6.2 Packing, weights and dimensions ........... 31 5.6.3 Wave Unit housing ................31 5.6.4 Handles ...................
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Page 7: Introduction
The power converter is suitable to accept a wide input voltage range from 10V up to 30V DC. The data format of the Wave Unit is compatible with the format as sent out by a DWR-MkIII and can be used with the Waves4 software package and/or libdatawell library. -
Page 9: Maintenance
2 Maintenance During the operational life of your Wave Unit it will require some maintenance even though it may function without error. We recommend to inspect the Wave Unit on every possible occasion in order to prevent possible malfunctioning. This chapter indicates which parts need servicing and when. Rather than extensively describing the full maintenance procedure, this chapter gives a short summary. -
Page 11: Trouble Shooting
3.1 Wave Unit diagnosis The Wave Unit has been provided with a processor board, which processes the digital signals to the serial communication channel. This channel is available for host access. For the processor board is a common part in most products of Datawell’s product range, it has some redundant circuitry when using it in this Wave Unit application. -
Page 13: Repair
TEL: 023 5316053 4.3 Serial numbers If you have any questions regarding your Wave Unit or if you encounter problems and you wish to contact Datawell, it is important to have the serial number at hand as listed on the text plate... -
Page 15: Reference
5 Reference This is the largest chapter by far. All Wave Unit functions and parts will be discussed here. To start with, the various components of the Wave Unit, their names and location will be introduced. You will be guided through the lid assembly and the stainless steel housing assembly, and packing, first in general, then in detail. -
Page 16: Wave Unit Parts
Unit the connection box is available for making the connections to the host unit. 5.2.3 Packing The Wave Unit is packed on a wooden plate, secured with 4 bolts and nuts. 5.2.4 Stainless steel housing On the outside of the stainless steel housing you will find, from the bottom up: the mounting flange, the cylindrical housing with in the upper flange, the forward shipping reference and the groove for the rubber sealing ring;... -
Page 17: Lid Assembly
To ensure proper functioning of all the electronics drying agent bags have been added at the appropriate places. 5.2.5 Lid Assembly A whole range of printed circuit boards each with its own functionality and its own location has been positioned onto the lid assembly. Figure 5.2.5.1 schematically shows the location of the boards;... -
Page 18: Wave Motion Sensors
Two mutually perpendicular accelerometers are mounted in the Wave Unit which measure the horizontal motion in case the Wave Unit is in the upright position. In case of tilt, the pitch and roll angles are determined by coils around the sensor sensing the electromagnetic coupling with a coil on the stabilized platform. -
Page 19: Wave Unit Axes And References
Note that an accelerometer sensor actually is a force sensor and that with a tilted Wave Unit the force of gravity will act as an inertial force. If you add that the direction of acceleration is opposite to the direction of the inertial force or gravity force, you will understand why A is negative. -
Page 20: Inspection Of The Fluid Level
-axis always points up and is fixed to the stabilized platform. For a tilted Wave Unit the orientation is the same as for an upright Wave Unit, which may be verified by tilting the Wave Unit. 5.3.4 Inspection of the fluid level As mentioned in Chapter 2 Maintenance it is important for the stabilized platform and vertical accelerometer sensor to periodically check the fluid level within the plastic sphere. -
Page 21: Sensor Fluid And Temperature
It should stay below 1º. To test the stability, leave the Wave Unit at rest on a trolley for a while. Then start logging the Wave Unit motion. Push and stop the Wave Unit fiercely thus moving it a few metres. In particular, the horizontal displacements will show disturbances at the natural swinging period of 40 s of the stabilized platform. -
Page 22: Pitch And Roll
Unit from accurately measuring the waves. The following is however quite dependant on the application the Wave Unit has been built-in, but at higher frequencies, when positioned in a hull type of buoy, the wave wavelength becomes comparable to the buoy dimensions and the buoy will not be able to follow the particular waves anymore (geometric attenuation). - Page 23 Specifications* for the Wave Unit when built into a 90 cm sphere and moored with a horizontal elasticity of 30 N/m . See Table 5.3.11.1. Table 5.3.11.1 Specifications of Wave Unit. Heave Range -20 m - + 20 m Resolution...
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Page 24: Data Processing
5.4 Data processing The Wave Unit sensor generates raw north, west and vertical displacements at a rate of 1.28 Hz. Displacements refer to excursions from the average position and should not be mistaken for position changes relative to the previous position. -
Page 25: Wave Direction Spectrum
where frequencies range from 0.0 Hz to 0.64 Hz in steps of 0.005 Hz. Actually, there is one more step, all coefficients are smoothed according to (5.4.1-6) To limit the number of frequencies low frequency coefficients (f ≤... - Page 26 Thus, one obtains: (5.4.2-6) (5.4.2-7) Given these components a whole set of informative wave parameters such as: wave direction, direction spread, wave ellipticity can be obtained. Before discussing their meaning in more detail, first, all formulas will be given.
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Page 27: Data Format
5.5.1 Wave Unit serial message format The Wave Unit sends out the 64 bits vector packed in a message format preceded by two characters of status and a two character counter and trailed by a carriage return: SSNN, VVVV, VVVV, VVVV, VVVV<CR>... -
Page 28: Datawell Real-Time Format
MSB = 1 means negative. Table 5.5.2.1.1 shows the organization of the 64-bit vector. Table 5.5.2.1.1. Organization of real-time displacements in 64-bit vector. Cyclic data Real-time displacements (1 cm/bit)* Parity bits see text Wave Unit vertical North west 16 bits... - Page 29 5.5.2.2 Spectrum file or full wave spectrum One level further up the cyclic data contained within 18 vectors forms one block. The cyclical data is organized as shown in Table 5.5.2.2.1. One block provides information on spectral parameters at 4 frequencies. The parameters are: ...
- Page 30 5.5.2.3 System file All system file words of 16 blocks are combined into one system file. A complete system file consists of 16 words from 16 consecutive blocks. It takes 16×18 = 288 vectors to acquire one system file. Table 5.5.2.4-2 below shows the significance of the system file data. Bits in the 12- bits word are numbered 0 through 11 with bit 11 MSB and bit 0 LSB.
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Page 31: Stainless Steel Housing And Lid Assembly
When lifting or moving the Wave Unit you can use the two handles present on the lid. 5.6.5 Lid, serial number and FS direction By lifting the lid the interior of the Wave Unit can be accessed. Almost all parts within the stainless steel housing can then be serviced or even replaced. A small V-shaped groove... -
Page 32: Drying Agent Bags, Plywood
Wave Unit from condensing water vapour bags of drying agent are packed inside the Wave Unit. Perforated sealing bags are used to slow down the drying process. The colour of the humidity indicator should be blue. If the colour has turned pink, the paper bags (without plastic sealing bag) should be dried at a maximum temperature of 110 ºC for approximately 12 hours. - Page 33 The connection box on top of the lid has been provided with a waterproof feed through connection to the inside of the Wave Unit. Hence, if the lid has been properly fitted to the housing and the power and communication cable are properly fed through the connection box entry, you may expect a watertight application.
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Page 34: Power Supply And Consumption
The Wave Unit’s nominal power consumption is less than 400 mW. The applied voltage from the power supply must be in the range of 10-30V. For proper start-up of the wave unit the power supply must be able to deliver at least 200mA. This current is only required when the unit is switched on. -
Page 35: Website
5.8.4 Website Our website www.datawell.nl will inform you of new Datawell products and developments. 5.8.5 FAQ Datawell maintains a Frequently Asked Questions list with answers about products and services. Go to the Datawell website www.datawell.nl and click <Support>, <FAQ>. 5.8.6 Datawell Bulletin About twice a year Datawell composes an e-mailing on new products and services.