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FT742 – Digital (RS485) Wind Sensor Manual
FT TECHNOLOGIES LTD.
SUNBURY HOUSE
BROOKLANDS CLOSE
SUNBURY-ON-THAMES
MIDDLESEX TW16 7DX
A4278-3-EN
October 2017
The FT and Acu-Res logos are registered trademarks of FT Technologies Ltd.
Copyright © 2017 FT Technologies Ltd. All rights reserved.
1
Direct-Mount Variant
FT742-DM (RS485) Sensors – User Manual
TEL: +44 (0)20 8943 0801
FAX: +44 (0)20 8943 3283
WEB:
www.fttechnologies.com
E-MAIL: info@fttechnologies.com
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Table of Contents
Summary of Contents for FT FT742
- Page 1 BROOKLANDS CLOSE WEB: www.fttechnologies.com SUNBURY-ON-THAMES E-MAIL: info@fttechnologies.com MIDDLESEX TW16 7DX A4278-3-EN October 2017 The FT and Acu-Res logos are registered trademarks of FT Technologies Ltd. Copyright © 2017 FT Technologies Ltd. All rights reserved. FT742-DM (RS485) Sensors – User Manual...
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Page 2: Table Of Contents
FT054 Evaluation Cable ....................27 SENSOR COMMUNICATION ................29 Introduction ........................29 RS485 Protocol ........................29 Configuring the Sensor ..................... 30 Communication ........................30 5.4.1 Conventions used in this manual ..................30 5.4.2 Data Transmission ......................31 FT742-DM (RS485) Sensors – User Manual... - Page 3 UC.5: Set & Query User Calibration Table Label ............62 6.4.26 US: Set or Query Saved Parameters ................63 6.4.27 WV Polar: Query the Wind Velocity Reading .............. 65 6.4.28 WV NMEA: Query the Wind Velocity Reading ............66 FT742-DM (RS485) Sensors – User Manual...
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Page 4: Product Symbols
Cela doit être fait par le should be done by returning the product to retour du produit à FT Technologies FT Technologies or by using an appropriate ou en utilisant une entreprise waste disposal company. This product d'élimination de déchets. Ce produit should not be disposed of in general waste ne doit pas être éliminé... -
Page 5: Safety Instructions
In accordance with the instructions set out in this manual, observing all information, warnings and instructions In accordance with any other instructions or guidance FT Technologies provide • To ensure that the product remains compliant with the electrical safety requirements of the UL / CSA 61010-1 Standards it must be;... -
Page 6: Consignes De Sécurité
Conformément aux instructions figurant dans ce manuel et en observant toutes les informations, avertissements et instructions Conformément à d'autres instructions ou directives que FT Technologies fournit • Pour garantir que le produit reste compatible avec les exigences de sécurité électrique de l'UL/CSA 61010-1 normes, l'équipement doit être :... -
Page 7: Introduction
FT sensors are configurable and can be factory programmed to the required customer settings, contact FT Technologies for further details. Note: The FT742-DM range is not suitable for turbine control applications. The FT742-FF and FT742- PM ranges are designed for this application. -
Page 8: Disclaimer
The Purchaser assumes all risks and liability in conjunction with the use of the information given. Any warranty given by FT Technologies in respect of the equipment is conditional upon the sensor being handled, installed, integrated and operated in accordance within the guidelines given in this manual. -
Page 9: Functional Description
3. See safety instruction requirements (page 5 and 6). 4. The heater set point, current limit and maximum power limits can be pre-configured in the factory or adjusted using the FT Acu-Test Digital kit. FT742-DM (RS485) Sensors – User Manual... -
Page 10: Wind Speed Calibration
Wind Speed Calibration All FT742-DM wind sensors get calibrated in the FT production wind tunnel before dispatch. As the sensor has no moving parts, there is no need to recalibrate a sensor over its lifetime as no measurement degradation will occur. -
Page 11: Electronic Rotation Of The Datum Direction
This setting can be programmed by the factory, by using the Acu Vis Test software (see Section 4.4) or the heater software commands (see Section 6.4.11). FT742-DM (RS485) Sensors – User Manual... -
Page 12: Low Power Operation
Section 2 Functional Description It is important to consider cable resistance losses and use a suitably rated cable of an appropriate length. FT recommends cable types in Section 3.2 and the cable length should not exceed 15m. If longer cables runs are required, consider the use of a junction box and heavy-gauge cable. -
Page 13: Mechanical & Electrical Installation
This section is for guidance only. It is the responsibility of the designer and installer to ensure that the installation and its design is fit for purpose. Please see Disclaimer Section 1.4. FT742-DM (RS485) Sensors – User Manual... - Page 14 The following replacement parts are available: FT027 O-ring (3.53 CS x 32.92 ID) Size Adaptor 25mm (1”) for FT742-DM (includes a FT033 tapered pipe insert & 4x FT034 FT031 self-locking fasteners) Size Adaptor 50mm (2”) for FT742-DM (includes a FT033 tapered pipe insert & 4x FT034...
- Page 15 Section 3 Mechanical & Electrical Installation FT742-DM (RS485) Sensors – User Manual...
- Page 16 Section 3 Mechanical & Electrical Installation Figure 5: Direct Mount Sensor (mm) FT742-DM (RS485) Sensors – User Manual...
- Page 17 The sensor measures the wind direction relative to the alignment flat and the central datum feature. When the wind sensor is correctly aligned the wind direction measurements will be as shown in Figure 6. Figure 6: Wind Direction (view from above) FT742-DM (RS485) Sensors – User Manual...
- Page 18 Confirm the installation is safe and appropriate for the environment. FT provides optional size adaptors to suit mounting diameters of 25mm (FT031) and 50mm (FT032). Ensure the internal diameter allows the interface cable to pass through. Pipe Insert (FT033)
- Page 19 Section 3 Mechanical & Electrical Installation Figure 8: Direct-Mount Compass Alignment FT742-DM (RS485) Sensors – User Manual...
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Page 20: Connector Details
In an area with a moderate or severe lightning strike exposure the cable shield may not provide sufficient protection. In this case the cable will require further shielding such as being enclosed in a metal pipe or conduit. FT742-DM (RS485) Sensors – User Manual... -
Page 21: Lightning, Surge & Emi Protection
3.3 Lightning, Surge & EMI protection The FT742-DM is specifically designed for meteorological use. When installing the sensor it is essential to do so in a way that protects the sensor in the event of a lightning strike, if the site is deemed to be at risk. Since current levels during lightning strike can be in the order of 200kA, applying the correct grounding technique is critical, so that the current is diverted to ground in a controlled manner. - Page 22 Pipe-Mount (PM) range of sensors. In such applications, a different grounding method should be employed and the Pipe Mount variant is a more suitable solution. Please contact FT Technologies for further information. FT742-DM (RS485) Sensors – User Manual...
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Page 23: Service, Configuration & Testing
When water enters the measurement cavity the surface helps to wash away dust and debris which may have settled. If any debris is present this can be removed by gently rinsing the measurement cavity FT742-DM (RS485) Sensors – User Manual... -
Page 24: Fault Finding & Troubleshooting
The following replacement parts are available: FT027 O-ring (3.53 CS x 32.92 ID) Size Adaptor 25mm (1”) for FT742-DM (includes a FT033 tapered pipe insert & 4x FT034 self- FT031 locking fasteners) Size Adaptor 50mm (2”) for FT742-DM (includes a FT033 tapered pipe insert & 4x FT034 self-... -
Page 25: Returns
Please contact FT Technologies for further information and advice if required. 4.3 Returns If a sensor appears to be faulty, compile a detailed fault description for each sensor, then contact FT Technologies to request a Returns Materials Authorisation (RMA) form. Please complete the form and return as instructed. -
Page 26: The Acu-Test Pack
4.4 The Acu-Test Pack To help users carry out a test bench assessment of the digital sensors, FT Technologies sells an Evaluation test Pack. This includes Acu-Vis software and the FT054 digital test cable. The test cable allows for connection between the sensor, an external supply and PC via a Type A USB connection. -
Page 27: Ft054 Evaluation Cable
Figure 12: Electronic diagram Warning: Live connection/disconnection of the power and/or sensors during live operation, or miswiring of the power leads could damage the equipment and is not covered by FT’s standard warranty terms. Figure 13: Acu-Vis Heater Controls Heater Settings: Displays the Heater setpoint value (°C). - Page 28 Figure 15: Windows driver installation sequence 5. Once the above sequence is complete, wait approximately 10 seconds and then run Acu-Vis by selecting the shortcut icon on the desktop or from the start menu in the FT Technologies folder. Figure 16: Acu-Vis Shortcut Icon 6.
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Page 29: Sensor Communication
The sensor features an easy to use ASCII-based communication protocol transmitted over an RS485 serial link. The protocol incorporates checksum validation to ensure the integrity of all data transmissions. In addition to the FT Technologies proprietary protocol the sensor can output the common NMEA 0183 MWV (Wind Speed and Angle) sentence. -
Page 30: Configuring The Sensor
Start of message delimiter Checksum field delimiter Field delimiter Dash <cr> Carriage return End of message delimiter Line feed <lf> <name> Placeholder for data Figure 18: Symbols used in this Handbook FT742-DM (RS485) Sensors – User Manual... -
Page 31: Data Transmission
See Section 5.4.5 for information on how to compute the checksum and Section 5.4.6 if checksum message validation is not required. All messages are terminated with a carriage return <cr> and line feed <lf>. FT742-DM (RS485) Sensors – User Manual... -
Page 32: Listener And Talker Identifiers
ASCII characters ‘//’ in place of the checksum value. Example: Send a message to set the data output format to Polar using the DFP command (the sensor Listener ID in this example is set to 02) FT742-DM (RS485) Sensors – User Manual... - Page 33 $02DFP*//<cr><lf> A checksum value is always transmitted by the sensor with every outgoing message. However the checksum field can be ignored by the host computer if checksum validation for received messages is not required. FT742-DM (RS485) Sensors – User Manual...
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Page 34: Parameter Settings
Section 6 Parameter Settings 6 PARAMETER SETTINGS FT sensors are configurable. The factory default settings can be modified on despatch to the required customer settings. 6.1 Command Types 6.1.1 Set Commands Figure 22 lists the commands that may be sent to the sensor from the host computer that are used to SET configuration options for the wind sensor. -
Page 35: Query Commands
Wind speed table record 6.4.23 Table label 6.4.24 6.4.25 Saved User Parameters Matches Saved to Current User Parameters 6.4.26 6.4.27 Wind velocity reading Wind Speed, Direction and Sensor Status 6.4.28 Figure 23: Query Commands FT742-DM (RS485) Sensors – User Manual... -
Page 36: User Calibration Table
Read the number of table entries and the table checksum; • Read out a selected row of table data, • Read out the User Calibration Table label. See Sections 6.4.21 - 6.4.25 for further details. FT742-DM (RS485) Sensors – User Manual... -
Page 37: Timing Constraints
A QUERY can then be sent to confirm command has been carried out: $//DF?*//<cr><lf> Then wait 50-100ms for the sensor to send a response: $WI,DF=P*5D<cr><lf> Please note the above example assumes the sensor has a factory default time delay of 50-100ms (DL01). FT742-DM (RS485) Sensors – User Manual... -
Page 38: Command Parameters
If you do not know what the current setting of the sensor baud rate is you will need to try each baud rate in turn until you establish communication. FT742-DM (RS485) Sensors – User Manual... -
Page 39: Cf: Set Or Query The Wind Datum Offset Angle
If the sensor’s location is changed then the offset value must be changed to suit the new installation or set to zero otherwise incorrect wind direction readings will be obtained. FT742-DM (RS485) Sensors – User Manual... -
Page 40: Cu: Set Or Query The Continuous Update Setting
WARNING: Do not use the continuous update mode if there are other talkers connected to the data bus. Only one active talker is allowed on the data bus at any one time otherwise bus contention will occur FT742-DM (RS485) Sensors – User Manual... -
Page 41: Df: Set Or Query The Wind Velocity Data Format
NMEA 0183 Format: The sensor returns the wind angle (0-359 degrees, Relative) and wind speed (m/s, knots or km/h). The sensor TalkerID is always set to WI when NMEA format is selected irrespective of any value that may have been set with the ID command. FT742-DM (RS485) Sensors – User Manual... -
Page 42: Dg: Query The Run-Time Counter
Use the DG command to query the number of operational hours that the anemometer has been in use. The Run-Time Counter is incremented on completion of each full hour that the anemometer has been in use. FT742-DM (RS485) Sensors – User Manual... -
Page 43: Dl: Set Or Query The Command Delay Interval
For example, if the delay interval is set to 250ms then the sensor will commence outputting the wind velocity data between 250-300ms after receiving a WV query command. If any further commands are sent to the sensor before the delay interval has elapsed they will be discarded. FT742-DM (RS485) Sensors – User Manual... -
Page 44: Er: Query Or Reset The Error Report
The historical log is stored in Flash and is retained when the power is switched off or the sensor software reset. This report can be sent back to the FT factory for analysis if there are problems with the sensor. -
Page 45: Fl.1: General Filter Settings
Comment $01,FLD*//<cr><lf> Disable filtering $01,FL?*//<cr><lf> Query filter setting $WI,FL=D*41<cr><lf> Sensor response Description Use the FL command to enable or disable moving average filtering of the wind speed and wind direction readings (see Section 2.3). FT742-DM (RS485) Sensors – User Manual... -
Page 46: Fl.2: Set Or Query Filter Lengths
1. So setting a filter to a length of 0001 gives just the current reading (see Section 2.3). The sensor’s internal memory is large enough to retain 64 previous speed and direction readings, allowing for maximum filter length of 6.4 seconds. FT742-DM (RS485) Sensors – User Manual... -
Page 47: Fl.3: Set Or Query The Selective Filter
This scheme can be enabled by factory configuration. The filter is turned off by default to match legacy behaviour. Depending on the control system used, this may improve data quality. FT742-DM (RS485) Sensors – User Manual... -
Page 48: Ht.1: General Heater Settings
It is also possible to query the duty cycle of the heater, which specifies the percentage of the current being drawn by the heaters. By default the heater requires a minimum voltage of 11VDC, see Section 6.4.13 for further details. FT742-DM (RS485) Sensors – User Manual... -
Page 49: Ht.2: Delay Heater Settings
Sensor response Description Use the HT command to set the sensor heater parameters, including setting a delay time which specifies how many seconds will elapse after powering on the sensor before the heater is enabled. FT742-DM (RS485) Sensors – User Manual... -
Page 50: Ht.3: Limit Heater Settings
Set current and voltage Limit $01,HT?L*//<cr><lf> Query heater settings $WI,HT=3.3,12*12<cr><lf> Sensor response Description The HT command may be used to set the sensor heater parameters such as the maximum current and under voltage limit of the heaters. FT742-DM (RS485) Sensors – User Manual... -
Page 51: Id: Set Or Query The Listener & Talker Identifiers
Note: the ID? command must use the new listener ID otherwise the command will not be recognised. Description Use the ID command to set the listener and talker address identifiers. See Section 5.4.4 for information on listener and talker address identifiers. FT742-DM (RS485) Sensors – User Manual... -
Page 52: Mm: Reset Or Query The Min/Max Recorded Wind Speed
Use the MM command to query the minimum and maximum wind speed readings that the sensor has recorded since it was last switched on. The minimum and maximum readings are set to their default values when an MMR, an RS or a DF set command is executed. FT742-DM (RS485) Sensors – User Manual... -
Page 53: Os: Overspeed Warning Scheme
Disable the Overspeed Warning scheme. Verify that the command has been accepted. Message Comment $01,OSD*//<cr><lf> Disable the scheme $01,OS?*//<cr><lf> Query Overspeed Warning scheme $WI,OS=D*57<cr><lf> Sensor response Description Use this command to query, enable or disable the Overspeed Warning Scheme (See Section 2.7). FT742-DM (RS485) Sensors – User Manual... -
Page 54: Pr: Query The Parameter Report
$WI,PR=076B63,0000,19,29,BF*7C<cr><lf> Sensor response Description Use the PR command to generate a sensor report. This report can be sent back to the FT factory for analysis if there are problems with the sensor. Currently the parameter report is only used for factory diagnostic purposes. -
Page 55: Rs: Reset The Sensor
To restart the software, but load the saved parameter settings use the RSS command. To restart the software, but load the factory default parameter settings use the RSF command. See command US (Section 6.4.26) for a description for setting or querying these Saved Parameters. FT742-DM (RS485) Sensors – User Manual... -
Page 56: Sn: Query The Serial Number And Platform Version
The serial number format starts with a 5 digit batch code, followed by a 3 digit number which identifies a sensor within a particular batch. The overall number is the unique serial number identifier for the sensor. FT742-DM (RS485) Sensors – User Manual... -
Page 57: Query The Software Version
Software version of the sensor. The spaces are reserved for future use. Examples Example 1 Read the software version number Message Comment $01,SV?*//<cr><lf> Query software version $WI,SV= *00<cr><lf> Sensor response Description The SV command returns the software version of the sensor. FT742-DM (RS485) Sensors – User Manual... -
Page 58: Uc.1: General User Calibration Settings
(nn) will be 00 and the saved user calibration table Flash copy checksum (zzzz) will be 5535. When the User Calibration facility is enabled, the uncorrected wind speed indication of the sensor is calibrated according to the stored calibration records, using linear interpolation. FT742-DM (RS485) Sensors – User Manual... -
Page 59: Uc.2: Clear User Calibration Table Record
A UCCLEAR is performed before a new user calibration table is loaded (see Section 6.4.23). The user calibration table label is also cleared to 32 ASCII spaces when the UCCLEAR command is sent (see Section 6.4.25). FT742-DM (RS485) Sensors – User Manual... -
Page 60: Uc.3: Set User Calibration Table Record
Up to 64 records can be entered sequentially into the sensor’s RAM and verified. Once sufficient records have been loaded, these can be saved to the Flash using the user calibration save command (see Section 6.4.24). FT742-DM (RS485) Sensors – User Manual... -
Page 61: Uc.4: Save And Read User Calibration Table
Use the UC?R command to verify the data stored in an individual Flash calibration record. Once the table has been saved into Flash memory, new data and the text string can only be written to it by first clearing the table. FT742-DM (RS485) Sensors – User Manual... -
Page 62: Uc.5: Set & Query User Calibration Table Label
The user calibration table label can be cleared by using the UCCLEAR command. (see Section 6.4.22) This resets the label to 32 ASCII spaces. UC?T query command will only return a response after the user calibration table has been initialised. FT742-DM (RS485) Sensors – User Manual... -
Page 63: Set Or Query Saved Parameters
The Factory Parameters retain the original default settings and cannot be modified, but can be used to replace the User Parameter, by using the RSF command (see Section 6.4.18) Continued over the page… FT742-DM (RS485) Sensors – User Manual... - Page 64 User version becomes corrupt there is always a ‘clean’ back up Saved copy of the parameters that can be used to recover the sensor. FT742-DM (RS485) Sensors – User Manual...
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Page 65: Wv Polar: Query The Wind Velocity Reading
It is important that the host computer is able to cope with occasional periods when valid data may be temporarily unavailable. The status is cleared once the WV command is executed, provided that the error condition does not persist. FT742-DM (RS485) Sensors – User Manual... -
Page 66: Wv Nmea: Query The Wind Velocity Reading
MWV Wind Speed and Angle sentence. The sensor Talker ID is always set to WI when NMEA format is selected, irrespective of any setting that may have been set with the ID command. End of Manual – Back to Contents FT742-DM (RS485) Sensors – User Manual...
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