Delta-T WS-GP1 User manual

WS-GP1 Weather Station
WS-GP1 Weather Station for wind speed and direction, relative
humidity, air temperature, rain and solar radiation
Quick Start Guide Version 1.0
Delta-T Devices Ltd

Introduction
The WS-GP1 Weather Station measures wind speed and direction, air temperature,
relative humidity, solar radiation and rainfall.
Apart from the wind vane tail, the sensors are already attached to the cross-arm and
connected to a GP1 Logger with a weather station program installed.
This guide explains how to choose a site, install the mast, mount and align the cross
arm, add the wind-vane tail and align it to North. Then, using a PC or Windows Mobile
Device we show how to change the weather station program, check the sensor
readings, then acquire and display readings.
1 Unpacking
Check your contents against your order.
You should have a cross arm fitted with a GP1
logger pre-wired to:
Wind speed and direction sensor D-034B-CA
RH and air temperature sensor RHT3nl-CA
Solar energy flux sensor PYRPA-03
Rain gauge RG2+WS-CA
You should also find the following:
Sensor user manuals
GP1 Quick Start Guide and screwdriver
Allen keys - 5/64 inch for the wind vane and 2.5 mm for light sensor levelling mount
Spanner for the mast
GP1-RS232 serial cable
Delta-T Software and Manuals CD including DeltaLINK PC version 2.3 or later
You may also have the following:
Tripod mast M2-TRPD or some other mast to mount on
Guy wire support kit WS-GWSK
t er tools you may need:O h
Spirit level for ensuring mast is vertical
Pick axe and shovel if the site needs preparing for the mast
Mallet for ground stakes if used
Steps, box to stand on, or mirror, to see bubble level on light sensor
PC running DeltaLINK-PC or PDA running Pocket DeltaLINK version 2.3 or later
Page 2 © 2007 Delta-T Devices Ltd

2 Choose the Location
Results depend not just on sensor accuracy and reliability but also on how
representative the site is – so choose the site carefully.
Where data is to be compared to a “standard” meteorological site, the sensors should
be exposed in a similar way to sensors at the standard sites, i.e. over a level surface of
short grass and away from trees or buildings.
These are rough guidelines. Refer to meteorological publications for further advice.
e.g. http://www.wmo.int/web/www/IMOP/WebPortal-AWS/Index02.html
Rules of thumb
© 2007 Delta-T Devices Ltd
Near a building, mount the sensors outside
the zone of influence. Horizontally this
extends roughly twice the height of the
building upstream and ten times
downstream. Vertically it extends to about
twice the height of the structure.
If the requirement is to measure the true
local conditions, e.g. a field of newly planted
corn, select a relatively uniform area of the
terrain. Be aware that, as a crop grows up
towards the sensors, the measured wind
speed decreases as the canopy
approaches.
Sensors are also influenced by the c
local thermal and humidity microclima
above the crop. There are no simple rules
to follow – but be aware of the following:
Clothes lin
hanging
te
e effect: vegetation upwind may
.
ater,
or glacier, is surrounded by a
rce. er
f
lacing objects directly under the air humidity and
temperature sensor, such as a solar panel, which can create a rising thermal plume
when warmed by the sun.
X
10X
2 X
2 X
Clothes line effect
Oasis effect
Leading edge effect
Rules of thumb
affect vapour gradients and heat transfer
Oasis effect: If an isolated source of w
e.g. a lake
relatively arid area, then the relative
humidity may be affected if the wind
direction draws air from the water sou
Leading Edge effect: When air moves ov
the boundary between two surfaces that
differ in temperature, moisture content,
roughness or some other characteristic, it
takes time for the air to adjust. The line o
discontinuity is known as the leading edge.
The boundary layer will vary in vertical
extent with distance from the leading edge
as it adjusts to the new conditions.
Thermal plume effect: Avoid p
Page 3

© 2007 Delta-T Devices Ltd
3 Attach wind vane
1 Fully insert vane arm into hub.
2 Align vane with centre axis of sensor.
3 Use the hex 5/64” Allen key to tighten
the set screw at the top of the hub.
4 Install mast and
cross arm
The cross arm can be mounted on any
sturdy vertical (or horizontal) mast of
diameter: 42 to 52 mm (1⅝to 2 inches).
Make the ground sufficiently level, firm and
stable to secure your mast. If using the
M2-TRPD tripod mast use the optional guy
wire kit with ground stakes to further
stabilise it.
Install the mast securely and as vertical as
possible using a sprit level.
Shield the logger from direct sun by
mounting the cross arm East to West with
the logger away from the Equator.
If using a solar panel, ensure it is not
immediately below the RH and air
temperature sensor.
Bolt cross arm to the mast - using the U-bolts and box wrench, and make it horizontal.
5 Orient the wind vane
Find true north
It is best to set the wind direction sensor to
true north, not magnetic north.
Compass Method: Get a compass and
the local angle of magnetic declination –
either from a map, local airport - or use an
online calculator e.g.
http://www.ngdc.noaa.gov/seg/geomag/jsp
Attach wind vane
South in the
northern
hemisphere
South in the
southern
hemisphere
A
B
Orient the cross arm East-West
/struts/calcDeclination
...and enter your latitude and longitude.
Magnetic declination (or variation) is the
angle between magnetic north and true
north.
It is positive when the angle measured is east of true north and negative when west.
So, if the declination is positive, true north is left of magnetic north.
+30°
MAGNETIC
NORTH
= 360M
TRUE
NORTH
=
= 270M
TRUE
NORTH
=0-(-30)
= 30M
-30°
N
S
E
W
N
S
E
W
+-
PLUS MINUS
Example: How to find true north given a compass
and the angle of magnetic declination
90
90
180 180
270
270
0-30
Page 4

Typical map of magnetic declination for y
he magnetic variation around the world can be quite large.
so it is best to refer wind direction to true north.
uthern Cross.
e True North intersects the horizon.
cking shoulder screw #231is in
ees, i.e.
mp
the cross arm,
ody until the count point to true
il points to true north).
oulder screw to
rotate freely.
r
ws supporting the light sensor to
hexagonal
r a box or use a
see the bubble level.
ear 2000
(reproduced courtesy of NOAA)
From this map you can see t
Magnetic north also drifts over time,
Star Method: Find the North Star or the So
Whichever method you use, establish wher
Orient the wind vane
1. Ensure that the lo
place on the hub. The wind vane cannot rotate and,
if read, the sensor should indicate 180 degr
south.
2. Using the spanner provided, loosen the cla
holding the O34B to
3. Rotate the housing b erweight and
the black arrow on the housing actually
south (and the wind vane ta
4. Tighten the clamp and remove the sh
release the wind vane and allow it to
6 Level the light senso
Adjust the tripod of scre
centre the bubble level, using the 2.5 mm
socket wrench provided .
Note: You may need to stand on steps o
mirror to
1See the D-034-CA Technical Manual on the Software and Manuals CD
Page 5 © 2007 Delta-T Devices Ltd

7 Install and Start GP1 Software
Install and start the GP1 software DeltaLINK on your PC as
instructed in the GP1 Quick Start Guide and connect to the Weather Station GP1
logger using the GP1-RS232 cable provided.
8 Examine the GP1 Program
1. Select the Program window. Factory installed weather stations will have the
WS-GP1 Weather Station Program pre-installed as shown
2. If e
se, New Program, WS-GP1 Weather Station Program and click OK.
Cin sensor tabs.
4. E lp for each tab.
Nand the choice of faster
s s, and modify them as
r
N
a
eem necessary
For definitions e.g. for the various wind
missing, to reinstall this program Click Change on th
elect Fil Program window and
3. lick on and examine the Air, Wind Sun and Ra
xamine the context sensitive online He
5. ote the default 1 hour Recording Rate in the Main tab
ampling rates for individual sensors in the Sensor tab
equired.
6. ote the various recording options such
s Average, Maximum, Time of
maximum and so on, and click the
check boxes as required.
7. Note the choice of units for wind run
and radiation integral.
8. Make any change you d
to the program and click Apply to install
it to the logger.
rose options: see the online Help.
Page 6 © 2007 Delta-T Devices Ltd

9 Check sensors & start logging
pan
3.
4. blo
5.
pl
6. gau
7. Click
w
8.
1. Select the Sensors
window and click the
Read now button. The
sensor readings will
continually refresh on a
scrolling time graph.
2. Observe the sensor
reading display in the
Select the Logger
scrolling charts and value
els.
Check the wind vane
reads 360 degrees at
north and 180 at south.
Spin the anemometer and
w on the radiation
shield and check the
readings look plausible.
Illuminate the light sensor
then cover it, and check
the readings seem
ausible.
Pour water into the rain
ge funnel to simulate
rainfall.
the Cancel button
hen finished.
window and click Start to
commence logging.
For help diagnosing sensor behaviour - from the Help menu (Alt H) select Document
tation Document Library
W
10 Collect and Save Logged Data
1. d data in the logger will be retrieved and
w seconds to download the data).
et file.
viously saved dataset file.
4. et file as a ASCII file for importing into other programs, open the file
s… selecting the appropriate file type to save.
Library (Alt D), and then WS-GP1 to display the Weather S
and refer to the individual sensor technical manuals.
eather Records
Select the Dataset window. All store
displayed on the screen (it may take a fe
Click Refresh if required.
Select File, Save to sa
2. ve the data to a datas
3. Select File, Open to open and view a pre
To save a datas
in DeltaLINK, and select File, Save A
Page 7 © 2007 Delta-T Devices Ltd

11 View Weather
in Dataset
V
Ri axis to
se cale options.
Le hart to mark out
ht-click to zoom.
Ri is to restore
the
Left click and drag top and bottom chart
e the chart
Ri on to pop up
a m cluding Hide,
ails options
Se
Ex elect
Do nd then
WWeather Station
Do rary mple WS-
GP t6 to
dis pical record. s outlined
ab
Display Options
iew
ght-click on the timescales
lect from the preset times
ft click and drag on a c
a zoom region. Then rig
ght click on the value ax
default zoom.
borders then click to resiz
ght click on the chart regi
enu of display options in
Show all Charts and Det
e also the online Help
ample Dataset
From the Help menu (Alt H) s
cument Library (Alt D), a
S-GP1 to display the
cument Lib
Double click on the file “Exa
1 Weather Station data.d
play a ty
Examine the display options a
ove.
No
ar te – Statistical symbols e only available if
© 2007 Delta-T Devices Ltd
Average
Time of
minimum
Maximum
Time of +1 standard
deviation
maximum
Minimum
Key to statistical
symbols % of time wind was from each direction:
% of windrun from each direction
% of wind energy from each direction
d was in each
4
5
6 and greater
Class Rose: % of time spee
Beaufort scale range
1
2
3
-1 standard
deviation
selected in the program
Page 8

Further processing your weather data
helps you seamlessly import data into MS ExcelDataset Import Wizard
spreadsheets. Multiple dataset files may be imported and the data interleaved.
See GP1 Quick Start Guide for instructions on using the Dataset Import Wizard.
Once your data is in Excel, many third-party Excel add-ins are available to help you
process your database.
Note: at the time of writing this document Excel can only graph up to 32000 lines of
data.
Moving the station
For its protection, remove the wind sensor vane before moving the weather station.
The blue box is NOT drop proof, so carry it carefully. Do not ship it by commercial
carrier without further protective packing.
Battery Life
Replace the battery before
the battery voltage indicator
drops below 5.5V.
At 1 reading/ minute on all
sensors a 9V Alkaline battery
may last 90 days.
To increase this, reduce the
reading frequency, and/or use
a lithium battery or external
lead acid battery.
The RH sensor dominates the
current consumption -
reducing RH sensor readings
to once every 5 minutes will
more than double battery life.
You might expect an external 10 Ahr lead acid battery to last longest, but internal self
discharge may limit this to 12 months at 25°C or only 3 months at 40°C. So unless it is
periodically recharged – for example by a solar panel - a lead acid battery may not
outlast a Lithium battery with its longer shelf life.
Note: When retrieving data, keep an eye on your logger battery. Its status is reported
by the logger software, and you can also log it along with the sensor readings. The
voltage reported is that presented to the sensors, and is slightly less than that at the
battery terminals.
Battery Life Estimator
0
200
400
600
800
0 102030405060708090100
Frequency of RH readings (minutes)
Life (days)
9V Lithium
9V alkaline
Page 9 © 2007 Delta-T Devices Ltd

Specifications
Specification
Logger Range/Notes GP1 ing) typical at 20°C
ding) max over -20°C to + 60°C
± (0.3mV+0.01% read
± (1.63mV+0.05% rea
Accuracy analog
±
⎠
0.07°C typical at 20°C
± 0.13°C max. (-20°C
© 2007 Delta-T Devices Ltd
to +60°C)
Readings > 600,000
Logging frequency 1s to 24 h
r
Data collection To PC or Pocket PC
Logging status Flashing LED
Environmental -20°C to +60°C, IP67
Wind speed ± 0.1m.s-
1
up to 10m.s-
1
(22.7 mph)
over 10m.s-
± 1.1% of reading
1
(22.7 mph)
Range 0 to 75m.s-
1
(0 to 167 mph)
4 m.s-
Starting threshold 0.
1
(0.9 mph)
4°
electrical
mechanical
Wind direction
Accuracy ±
0 to 356°
0 to 360°
Starting threshold 0.4 m.s-
1
(0.9 mp
Damping rat h) io .25
sensor and logger
0.5 °C at 3 m.s-
Resolution < 0.5°
Temperature
Accuracy at 25°C ± 0.2°C
IP65
1
1.0 °C at 2 m.s-
1
2.0 °C at 1 m.s-
1
RH ± 2% RH 5 to 95% RH
± 2.5% RH < 5% and > 95% RH
Envronmental -20 to 80°C, 0-100%RH IP65
Response time < 10s 90% of scale for a step change from
11% to 75% RH
Rainfall Sensitivity 0.2mm per tip up to 360 mm.hr-
1
Solar Radiation
Absolute accuracy ± 5%
Uniformit
y
± 3%
Repeatability ± 1%
± 1% 45°zenith angle
± 4% 75°zenith angle
Environmental -40 to 55°C, 0 to100%RH can be immersed
Cosine response
n Shield error
for 10K thermistor (at -20 to + 60°C)
Accuracy at 25°C
Temperature accuracy
Range
Radiatio
Accuracy
Page 10

Sensor Wiring
© 2007 Delta-T Devices Ltd
Service & Recali
Before returning parts please co
bration
ntact Delta-T or your local agent for instructions.
aceable in the field.
Note: the Windvane, though connected to
GP1 terminal Temp3, is actually read as a
voltage output sensor (0-2.5V equals 0-360
degrees). The internal circuit differs from the
standard MetOne O34B, see panel at right.
See also D-034B-CA Technical Manual on the Delta-T Software and Manuals CD.
Wind speed and direction D-034B-CA
Recalibrate: every year. Service: 6-12
months: look & listen to see if the vane and
cups are running freely, are undamaged, and
are not loose. 12-24 months: replace
anemometer bearings. 24-36 months:
complete factory overhaul of sensor.
Most parts are repl
10K
10K
5V (ref)
GND
Temp3 (IN)
Temp3 (GND)
green
yellow
Windvane circuit schematic
white
1M
1K
Colour Function GP1 connection
Black WS common GND
Pin 4 Green WD Common Temp3 (GND)
White WD +REF +5V (ref)
White/brown Shield GND
RH Signal - CH2 (-)
Blue Air temp + Temp4 (IN)
Yellow Air Temp - Temp4 (GND)
Red Power V+ CH2 (PWR)
Black Power V- CH2 (GND)
Screen Shield GND
either Switch NO Event 6
either Switch common GND
ion
Red Signal CH1 (+)
Black 5V power +5V (ref)
Clear Ground CH1 (GND) + CH1(-)
Rain
and direction
A
ranometer
nl-CA
rature
Wind speed & Direction:
Pin 1 Red WS signal Event 5
Pin 2
Pin 3 Yellow WD signal Temp3 (IN)
D-O34B-CA
Wind speed
Pin 5
Temperature & RH
White RH Signal+ CH2 (+)
Green
RHT3
Tempe
Rainfall
Solar Radiat
RG2
D-PYRPA-C
py
and RH
Page 11

Rain gauge RG2
an be recalibrated in the field.
See also the RG2+WS-CA Technical Manual on the Software and Manuals CD
Light sensor D-PYRPA-CA
consequential loss may occur. It is the responsibility of the user to ensure appropriate
safeguards are in place for regularly monitoring a
In no event shall Delta-T’s liability exceed the selling
indirect, incidental or consequential damages in connection w
but not limited to: data loss, vegetation loss, loss of
or services, property damage, or personal injury th
customer agrees to the limitations and exclusions
See also the GP1 Product Usage.pdf in the online
The WS-GP1 Weather Station is CE compliant, See WS-GP1 E
Document Library folder.
C
Typical drift 1% per year. Recalibrate every 2 years. Keep it clean and level.
Manufacture’s Warranty: 1 year parts and labour.
See also the D-PYR-PA Technical Manual on the Software and Manuals CD
RH & air temp sensor RHT3nl-CA
Typical drift -1.5 to -2% in the first year, -1% in the second year and -0.5% in the third.
No adjustment of the RH or temperature element is possible. Inaccurate sensors must
be replaced with new module which can be plugged in the field. Replace every two
years in clean atmospheric conditions or every year if the atmosphere is polluted.
Replacing the RH Sensor
Note: the RHT3nl uses a 10K Betatherm 10K3A1B thermistor and a 6 plate radiation
shield but is otherwise similar to the RHT2nl sensor.
See also the RHT3nl-CA Technical Manual on the Software and Manuals CD.
Notices
This product uses software code. It should not be used in safety-critical applications or where
nd checking the equipment.
price of the product. Delta-T is not liable for
ith the use of equipment, including
energy or water, cost of substitute equipment
at results from installer’s negligence. The
of liability by purchase or use of this product.
Document Library folder.
C Certificate.pdf in the online
16
23 4 5
Delta-T Devices Ltd
130 Low Road, Burwell
Cambridge CB25 0EJ
UK
Tel: [phone]
Fax: [phone]
e-mail: [email protected]
[e-mail]
web: www.delta-t.co.uk