Vaisala WXT510 MET Sensor Installation Notes

Vaisala WXT520 MET sensor installation notes Oct 5, 2009

This instrument provides Wind (Speed & direction), Air Temperature, Humidity, Barometric Pressure, and Rain (amount and intensity). It requires 12vdc (5-30 vdc) and has an RS485 data port (RS232 & RS422 are also possible). The sensor has a single character address (allowable= 0-9, A-Z, a-z). Factory default address and port protocol are: 19200,N,8,1 Addr=0. Oceanus port and stbd units are configured for 9600,N,8,1 Addr="P" & "S". Protocol and address changes are most easily accomplished using the Vaisala supplied software and USB test cable (configuration can be done without the test cable if necessary). See the “Hot Configuration Notes” below for information on changing the parameters of instruments already on the mast.

Installation Overview It seems best to use the supplied test cable and software to revise the factory communications settings. The test cable plugs into a connector on the bottom of the sensor and a computer USB port. The software allows changing a great many sensor configuration settings but it is only necessary to adjust the port protocol and the sensor’s address. The port should be set for RS485 at 9600,N,8,1 in order to be compatible with our ship’s other MET sensors. The address can be any single character; at present, the port and stbd sensors are addressed as "P" and "S" (previously "5" was used for single sensor installations). The data and power connection can be made using a connector mounted on the bottom of the sensor or by installing a supplied stuffing tube and running the cable to an internal terminal strip. Using the connector eases the problems associated with servicing the sensor but we may discover that the terminal strip is a better choice for our environment.

Standard Vaisala interface cable: Pin2 Brown Vin (12vdc) (Blue IMET cable wire) Pin8 Red or Clear Gnd for Vin ("clear" is the non-insulated drain wire) (Black IMET cable wire) Pin5 Gray Data+ (white IMET cable wire) Pin7 Blue Data- (brown IMET cable wire)

Pin4 Yellow Vh Heater power (5-30vdc or 30vac rms max) (Do not use sensor supply voltage) Pin6 Pink Gnd for Vh

Mounting: Sensor has a North arrow on the bottom that should point directly forward. An alignment error can be specified in the sensor configuration but none of the other wind sensors on our ships have this ability so, for consistency, the WXT520 alignment correction is made by Calliope. The Calliope correction value is the mounting offset angle; “+” if the North arrow points towards the stbd side. The Calliope alignment correction variable is WXT520PortOffset or WXT520StbdOffset, as defined in Calliope\Constants\WindSensors.dat

Sensor Initialization: The Calliope code includes an initialization function that will set the sensor parameters as discussed in the following paragraphs. Experience shows that this initialization only needs to be done once and it's not a good idea to repeat it unless changes need to be made. Therefore, initially the Calliope code should be run with “WXT520_init()” specified as the initialization function and then the WXT520’s setup should be changed to eliminate use of this function. Since the WXT520 can provide information on its configuration if requested, Calliope includes the “WXT520_info()” function that requests this data and stores it in a metadata file (MetaDataAux.txt) in the directory with the data files. Normally, this function is used to replace the WXT520_init function after Calliope has been run for a short time and the sensor has been initialized. The Calliope\Functions directory needs to have the file Initializations26.lib or newer (only one “Initializations##” file should have the “.lib” extension). This file will initialize the WXT520 (using WXT520_Init) and write the configuration information to the MetaDataAux.txt file in the Calliope data directory. The initialization code assumes the port protocol is 9600,N,8,1 but it obtains the sensor address from the polling address entered as part of the Calliope transaction definition (i.e. if PR0 is entered as the data request address, the initialization code will use “P” as the sensor’s address). This allows the same function to be used to initialize multiple sensors having different addresses.

The standard configuration results in a data string similar to the following:

PR0,Dm=048D,Sn=0.0M,Sm=0.1M,Sx=0.2M,Ta=24.5C,Ua=35.7P, Pa=1018.2H,Rc=0.00M,Ri=0.0M

PR0 = Instrument’s polled data request address & cmd Dm = Wind direction, deg (2 Hz samples, 10 sec average) “0” deg wind comes over the bow Sn = Wind speed min, m/sec (2 Hz, 10 sec sample period) Sm = Wind speed average, m/sec (2 Hz, 10 sec sample period) Sx = Wind speed max, m/sec (2 Hz, 10 sec sample period) Ta = Air temperature, degrees C Ua = Relative humidity, % Pa = Barometric pressure, hPa Rc = Rain accumulation, mm (accumulation is updated in 10 sec intervals) The accumulation value is reset only when the sensor power is reset. Ri = Rain intensity, mm/hour Hot Configuration Notes:

Most (all?) of the WXT520 basic communications configuration parameters can be changed after the instrument is mounted and providing data. The WXT520 instructions (Chapter 6) discusses the procedure, which utilizes the “XU” command. There is one trick to this: the command and terminating must be delivered faster than a normal person can type. Therefore the command needs to be sent as a pre-defined block rather than via a keyboard and terminal program.

There’s a simple way to make “XU” changes using Calliope. As an example, the following describes how to change a WXT’s address to “P”, assuming the instrument is installed and delivering data using address “5”.

1) Using the Calliope Editor, open the WXT’s definition window. The polling address should be \013\0105R0\013\010. 2) Change the polling address to \013\0105XU\013\010. DO NOT HIT “Done”! Instead, click on “View”. You should get a configuration message, most of which requires Chapter 6 information to understand. If you don’t get this message, figure out why before continuing. 3) Change the polling address to \013\0105XU,A=P\013\010 and click on “View”. This command is sent to address “5” and instructs the instrument to change its address to “P”. You should get back “PXU,A=P”. 4) Reset the polling address to request data but with the new instrument address (\013\010PR0\013\010) and click on “View”. If you get data, store the changes by clicking on “Done”.

Some changes require resetting the instrument (i.e. baud rate). This can be done with the “addrXZ” command or by cycling power. Calliope Setup: The sensor delivers an extensive data set so there are a considerable number of data items to be defined. The following example is for a port sensor:

WXTP_R0 Vaisala WXT520 Complete raw data string WXTP_Dm Wind direction Ship relative (not corrected for sensor alignment) WXTP_Sm Wind speed Ship relative WXTP_Ta Air temperature WXTP_Pa Barometric pressure WXTP_Ua Relative humidity WXTP_Rc Rain accumulation WXTP_Ri Rain intensity WXTP_TSD True wind speed & direction WXTP_TS True wind speed WXTP_TD True wind direction

The basic Calliope transaction definitions can be seen in the configuration report excerpt at the end of this document.

Sensor Configuration:

Vaisala WXT520 Configuration - Wind sensor: PWU,R=11111100&01011100,I=10,A=10,U=M,D=0,N=W,F=2 Pressure/Temperature /Humidity sensor: PTU,R=11010000&11010000,I=6,P=H,T=C Rain sensor: PRU,R=11111100&10100000,I=60,U=M,S=M,M=R,Z=M

Typical Metadata entries (port sensor):

WXTP Vaisala WXT520 Weather Transmitter (port) The sensor is mounted on the port side of the forward mast, 20m above the waterline.

Data Format: WXTP 39240.67178 16:07:22 5R0,Dm=048D,Sn=0.0M,Sm=0.1M, Sx=0.2M,Ta=24.5C,Ua=35.7P,Pa=1018.2H,Rc=0.00M,Ri=0.0M

WXTP 39240.67178 16:07:22 = Calliope designator and time values (time stamps are GMT) PR0 = Instrument’s polled data request cmd (“P” is inst address) Dm = Wind direction, deg (2 Hz samples, 10 sec average) Sn = Wind speed min, m/sec (2 Hz, 10 sec sample period) Sm = Wind speed average, m/sec (2 Hz, 10 sec sample period) Sx = Wind speed max, m/sec (2 Hz, 10 sec sample period) Ta = Air temperature, degrees C Ua = Relative humidity, % Pa = Barometric pressure, hPa Rc = Rain accumulation, mm (accumulation is updated in 10 sec intervals) Ri = Rain intensity, mm/hour

The rain accumulation value is reset only when the sensor power is reset. Wind speed and direction are given in meteorological terms: a “0” degree wind comes from the bow; a “90” degree wind comes from the stbd side. Wind speed and direction values are ship relative and direction has not been corrected for sensor mounting alignment error. Wind sampling is done at 2 Hz and averaged over 10 seconds – new data is available at 10 sec intervals.

WXTP_Dm Ship relative wind direction (degrees) not corrected for mounting alignment error. Data Format: xxx

Wind direction is given in meteorological terms: a “0” degree wind comes from the bow; a “90” degree wind comes from the Stbd side. Wind sampling is done at 2 Hz and averaged over 10 seconds – new data is available at 10 sec intervals.

WXTP_Sm Ship relative wind speed (m/s) Data Format: xx.x

Wind sampling is done at 2 Hz and averaged over 10 seconds – new data is available at 10 sec intervals.

WXTP_Rc Rain accumulation (mm) Data Format: xx.xx

This value continues to increase until the sensor is reset as the result of power cycling (data polling does not reset the count).

WXTP_Ri Rain intensity (mm/hr) Data Format: x.x

This value is calculated over 10 second intervals.

WXTP_TSD True wind speed (m/s) and direction (degrees) – Port sensor Data Format xx.x, xxx Values are calculated from the port Vaisala WXT520 Weather Transmitter raw data corrected for sensor alignment error and combined with the ship’s heading (gyro, Octans, Pos/mv, etc.) and GPS SOG and COG values.

WXTP_TS True wind speed (m/sec) Data Format xx.x

Values are calculated from the Vaisala WXT520 Weather Transmitter raw data corrected for sensor alignment error and combined with the ship’s heading (gyro, Octans, POS/MV, etc.) and GPS SOG and COG values.

WXTP_TD True wind direction (degrees)

Values are calculated from the Vaisala WXT510 Weather Transmitter raw data corrected for sensor alignment error and combined with the ship’s heading (gyro, Octans, POS/MV, etc.) and GPS SOG and COG values. Typical Calliope configuration information:

Defined constants: WindSensors.dat

// Wind sensor offset values. This is the angle of the sensor measured // from the centerline of the ship (clockwise from above). If the wind // sensor reports a 0.0 degree wind when the wind is approaching from 5 // degrees to stbd, the offset is +5. // For an IMET sensor, a 0.0 degree wind is indicated by 0.0 as the // first item in the wind data string. Additionally, the sixth item // (LastVane) will also be 0.0. // For a WXT520 sensor, a wind coming directly over the bow should // result in a WXTx_Dm value of 0.0 degrees.

IMETWindSensorOffset = 0.0 WXT520PortOffset = 0.0 WXT520StbdOffset = 0.0 WS425SensorOffset = 0.0

______

Sensor definitions: (SI=Service interval, LC=Log cycle, CC=Clear cycle, P=Priority)

WXT520 Port Vaisala MET sensor WXTP, Polled, Com3 Active; SI=10; LC=3; CC=3; P=0 Address = \013\010PR0\013\010 Terminator = \010, Terminator count = 1 Response time = 0.5 Init=WXT520_Info( ) C[0]=0, C[1]=0, C[2]=0, C[3]=0, C[4]=0, Hi_limit=0, Lo_limit=0, Max_diff=0 CSV flag clear Primary UDP output Stored value: PR0,Dm=114D,Sn=0.8M,Sm=1.3M,Sx=1.8M,Ta=14.9C, Ua=46.7P,Pa=1028.9H,Rc=0.00M,Ri=0.0M

Air temp; Port WXT520 (C) WXTP_Ta, Secondary, WXTP Active; SI=10; LC=10; CC=10; P=0 No Functions Equation = toNum(x[6]) (Start string=None) C[0]=0, C[1]=0, C[2]=0, C[3]=0, C[4]=0, Hi_limit=0, Lo_limit=0, Max_diff=0 CSV flag set, 1 decimal plcs No UDP output Stored value: 24.9

Baro press; Port WXT520 (hPa) WXTP_Pa, Secondary, WXTP Active; SI=10; LC=2; CC=2; P=0 No Functions Equation = toNum(x[8]) (Start string=None) C[0]=0, C[1]=0, C[2]=0, C[3]=0, C[4]=0, Hi_limit=0, Lo_limit=0, Max_diff=0 CSV flag set, 1 decimal plcs No UDP output Stored value: 1015.9

Rain accum; Port WXT520 (mm since last reset) WXTP_Rc, Secondary, WXTP Active; SI=10; LC=2; CC=2; P=0 No Functions Equation = toNum(x[9]) (Start string=None) C[0]=0, C[1]=0, C[2]=0, C[3]=0, C[4]=0, Hi_limit=0, Lo_limit=0, Max_diff=0 CSV flag set, 1 decimal plcs No UDP output Stored value: 0.25

Rain inten; Port WXT520 (mm/hr) WXTp_Ri, Secondary, WXTP Active; SI=10; LC=0; CC=0; P=0 No Functions Equation = toNum([10]) (Start string=None) C[0]=0, C[1]=0, C[2]=0, C[3]=0, C[4]=0, Hi_limit=0, Lo_limit=0, Max_diff=0 CSV flag set, 1 decimal plcs No UDP output Stored value: 0.0

Rel humidity; Port WXT520 (%) WXTP_Ua, Secondary, WXTP Active; SI=10; LC=2; CC=2; P=0 No Functions Equation = Rnd(toNum(x[7]),1) (Start string=None) C[0]=0, C[1]=0, C[2]=0, C[3]=0, C[4]=0, Hi_limit=0, Lo_limit=0, Max_diff=0 CSV flag set, 1 decimal plcs No UDP output Stored value: 47.0

Rel wind dir; Port WXT520 (deg) WXTP_Dm, Secondary, WXTP Active; SI=10; LC=2; CC=2; P=0 No Functions Equation = toNum(x[2]) (Start string=None) C[0]=0, C[1]=0, C[2]=0, C[3]=0, C[4]=0, Hi_limit=0, Lo_limit=0, Max_diff=0 CSV flag set, 0 decimal plcs No UDP output Stored value: 216

Rel wind spd; Port WXT520 (m/s) WXTP_Sm, Secondary, WXTP Active; SI=10; LC=2; CC=2; P=0 No Functions Equation = toNum(x[4]) (Start string=None) C[0]=0, C[1]=0, C[2]=0, C[3]=0, C[4]=0, Hi_limit=0, Lo_limit=0, Max_diff=0 CSV flag set, 1 decimal plcs No UDP output Stored value: 0.5

True wind dir; Port WXT520 (deg) WXTP_TD, Secondary, WXTP_TSD Active; SI=10; LC=0; CC=0; P=0 No Functions Equation = x[2] (Start string=None) C[0]=0, C[1]=0, C[2]=0, C[3]=0, C[4]=0, Hi_limit=0, Lo_limit=0, Max_diff=0 CSV flag set, 0 decimal plcs Primary UDP output Stored value:

True wind spd; Port WXT520 (m/s) WXTP_TS, Secondary, WXTP_TSD Active; SI=10; LC=0; CC=0; P=0 No Functions Equation = X[1] (Start string=None) C[0]=0, C[1]=0, C[2]=0, C[3]=0, C[4]=0, Hi_limit=0, Lo_limit=0, Max_diff=0 CSV flag set, 3 decimal plcs Primary UDP output Stored value:

True Wind spd & dir; Port WXT520 WXTP_TSD, Conversion, Null Active; SI=10; LC=3; CC=3; P=20 No Functions Equation = TrueWind_SD(WXTP_Sm.value, WXTP_Dm.value, WXT520PortSensorOffset) C[0]=0, C[1]=0, C[2]=0, C[3]=0, C[4]=0, Hi_limit=0, Lo_limit=0, Max_diff=0 CSV flag clear No UDP output Stored value: 3.4455 250.2