Gill Instruments WindObserver II User manual

WindObserver II (WindObserver FC)
Ultrasonic Anemometer
User Manual
Doc No. 1390-PS-0011
Issue 2
Gill Instruments Limited
Saltmarsh Park,
67 Gosport Street,
Lymington,
Hampshire.
SO41 9EG
UK
Tel: [phone]
Fax: [phone]
E-mail: [e-mail]
Website: www.gill.co.uk

Gill Instruments Ltd
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WindObserver II (WindObserver FC) Page 2 Issue 2
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WindObserver II (WindObserver FC) Anemometer

Gill Instruments Ltd
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Contents
1. FOREWORD............................................................................................5
2. INTRODUCTION......................................................................................5
3. FAST TRACK SET-UP ............................................................................5
4. SPECIFICATION .....................................................................................6
5. PRE-INSTALLATION ..............................................................................7
5.1. Equipment supplied .......................................................................................... 7
5.2. Installation requirements................................................................................... 7
6. INSTALLATION.......................................................................................8
6.1. Installation Guidelines....................................................................................... 8
6.2. Bench system test ............................................................................................ 9
6.3. Cabling ............................................................................................................. 9
6.4. Connections.................................................................................................... 10
6.5. Power supplies ............................................................................................... 12
6.6. Mechanical installation.................................................................................... 12
Location................................................................................................................... 12
Orientation .............................................................................................................. 12
Mounting bracket .................................................................................................... 12
Figure 1. Suggested mounting bracket and Earthing (grounding) arrangements .. 13
Alignment ................................................................................................................ 14
Figure 2a North marker and UV polarity definition (UV) format) and Mounting Ring14
Figure 2b WindObserver II (WindObserver FC) Outline Dimensions..................... 15
7. MESSAGE FORMATS & OPTIONS......................................................16
7.1. Wind Speed format ......................................................................................... 16
7.2. Output formats................................................................................................ 16
Output format .......................................................................................................... 16
7.3. Units ............................................................................................................... 16
7.4. Output rate...................................................................................................... 17
Sample Average ..................................................................................................... 17
7.5. Averaging ....................................................................................................... 17
7.6. Heating ........................................................................................................... 17
7.7. 45°Offset........................................................................................................ 17
7.8 Vertical Output Padding .................................................................................. 17
7.7. ASCII message format (UV and Polar) ........................................................... 18
ASCII UV format .................................................................................................... 18
ASCII Polar format .................................................................................................. 19
7.8. NMEA Format................................................................................................. 20
8. CONFIGURING......................................................................................21
8.1. Entering Configuration mode .......................................................................... 21
8.2. Returning to Measurement mode.................................................................... 21
8.3. Checking the configuration ............................................................................. 22
8.4. Changing settings ........................................................................................... 22
8.5. Output format.................................................................................................. 22
8.6. Unit Identifier .................................................................................................. 23
8.7. Units ............................................................................................................... 23
8.8. Output rate...................................................................................................... 23

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8.9. Averaging ....................................................................................................... 23
8.10. Heating ........................................................................................................... 23
8.11. NMEA ............................................................................................................. 23
8.12. Vertical Output Padding .................................................................................. 23
8.13. 45°Offset........................................................................................................ 24
Figure 3 UV Polarity............................................................................................... 24
8.14. Communications settings................................................................................ 25
Baud rate................................................................................................................. 25
Duplex mode........................................................................................................... 25
Data and parity options ........................................................................................... 25
ASCII Message terminator...................................................................................... 26
Scaling .................................................................................................................... 26
Polar mode direction wraparound........................................................................... 26
8.15. Configuration and Diagnostic Information ....................................................... 26
8.16. Message Format (Output String Padding)....................................................... 26
9. MAINTENANCE & FAULT-FINDING ....................................................27
9.1. Cleaning ......................................................................................................... 27
9.2. Servicing......................................................................................................... 27
9.3. Fault-finding.................................................................................................... 27
9.4. Returning unit ................................................................................................. 28
9.5. Status (error) codes ........................................................................................ 28
9.6. Bench test....................................................................................................... 28
Integrity Check Chamber (ICC) .............................................................................. 29
Integrity & Zero Wind Check ................................................................................... 29
10. APPENDICES........................................................................................30
10.1. Glossary & Abbreviations................................................................................ 30
10.2. Guarantee....................................................................................................... 31
10.3. Principle of operation ...................................................................................... 32
10.4. Electrical Conformity....................................................................................... 33
EC DECLARATION OF CONFORMITY ACCORDING.......................................... 33

Gill Instruments Ltd
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1. FOREWORD
Thank you for purchasing the WindObserver II (WindObserver First Class) manufactured
by Gill Instruments Ltd.
The unit has no customer serviceable parts and requires no calibration or maintenance.
To achieve optimum performance we recommend that you read the whole of this manual
before proceeding with use. Do NOT remove black “rubber” transducer caps.
Gill products are in continuous development and therefore specifications may be subject to
change and design improvements without prior notice.
The information contained in this manual remains the property of Gill Instruments and
should not be copied or reproduced for commercial gain.
2. INTRODUCTION
The Gill WindObserver II (WindObserver FC) wind sensor is a very robust, lightweight
unit with no moving parts, outputting wind speed and direction. The units of wind speed,
output rate and formats are all user selectable.
The WindObserver II (WindObserver FC) is supplied with de-icing heating
(recommended if icing is likely).
The WindObserver II (WindObserver FC) can be used in conjunction with a PC, data
logger or other device, provided it is compatible with the RS422 output.
The output message format is configured in Polar, NMEA (0183 Version 3); Continuous
output, other formats can be configured as detailed in Section 7 Message Formats &
Options.
WindObserver II (WindObserver FC) may be configured using standard communications
software on a PC. This is explained in Section 8 Configuring.
3. FAST TRACK SET-UP
If you are in a hurry to try out the WindObserver II (WindObserver FC), are familiar with
Gill equipment, and coupling to a PC using RS422, go to the following sections:
Section 6 Installation
Section 7 Message Formats & Options
Section 8 Configuring
After you have successfully set up the WindObserver II (WindObserver FC), we strongly
advise that you then go back and read the rest of the manual to ensure that you get the best
results from the WindObserver II (WindObserver FC).

Gill Instruments Ltd
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4. SPECIFICATION
Model 1390-PK-057
Measurement
Output 1Hz
Parameters UV, Polar, NMEA
Units m/s, Knots, MPH, KPH ft/min
Averaging Flexible 1-3600 seconds
Wind Speed
Range 0 - 75m/s
Accuracy ±2%@12m/s and ±6%@75m/s (estimated to be confirmed)
Resolution 0.01m/s
Offset ±0.01m/s
Direction
Range 0 - 359°
Accuracy ± 2°
Resolution 1°
Anemometer Status Supplied as part of standard message
Starting Threshold 0.01 m/s
Dead Band Wind Direction None
Power Requirement
Anemometer only 20-30 V DC (50mA Average)
Heating - Optional 3A @ 24V AC or DC
Digital Output
Communication RS422, full duplex, network facility
Baud rates 1200, 2400, 4800, 9600, 19200, 38400
Formats 8 data, odd, even or no parity
Dimensions
Size 405mm x 210mm
Weight 1.5kg (not including cable)
Materials
External Construction Stainless Steel 316
Environmental
Moisture protection IP66 (NEMA4X)
Operating temperature -55°C to +70°C
Humidity 5% to 100% RH
Precipitation 300mm/hr
EMC BS EN 50081-1: 1992 (Emissions class B)
BS EN 50082-2: 1992 (Immunity)
FCC class A
Icing MILSTD810E Method 521.1 Procedure 1
Standards Traceable to UK national standards
Site Calibration None required. (See Section 10.6 Zero Wind Check)

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5. PRE-INSTALLATION
5.1. Equipment supplied
WindObserver II (WindObserver FC) RS422 output and de-icing
and Installation kit (comprising a gasket and four Stainless Steel screws)
and WindObserver II (WindObserver FC) CD User Manual (this manual)
and Integrity Check Chamber (ICC) (Optional)
5.2. Installation requirements
Host system - One of the following:
 PC with an internal or external interface compatible with the RS422 output from
the WindObserver II (WindObserver FC).
 Other equipment with I/O compatibility to the WindObserver II (WindObserver
FC) option selected.
Software - One of the following:
 HyperTerminal (for Windows™ 9x and later), or Terminal (Windows™ 3.n),
normally already installed on a PC.
 Other Terminal Emulation software packages
Cable and Junction box
To connect between the WindObserver II (WindObserver FC) and the host system. The
unit is supplied with a 15m flying cable, requiring a mast mounted junction box (not
provided) for onward connection.
See Section 6.4 for connection details
The flying cable must be retained with a cable tie within 150mm of the base of the
anemometer.
Mounting Bracket
A mounting bracket is required (not provided) which will attach to the WindObserver II
(WindObserver FC) via the four tapped holes in the base of the unit. Always ensure that
the gasket supplied is fitted to the base of the anemometer.
It is important that the gasket supplied forms a watertight seal on the base of the
anemometer.
In the event that the mounting bracket supplied by the customer is not flat or does not
form complete support for the anemometer base; the customer must fit a mounting ring as
shown in Figure 2a.
See Section 6.6 for mounting details.

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6. INSTALLATION
Do NOT remove the black “rubber” transducer caps. Warranty is void if the
security seal is damaged or removed.
All the time the WindObserver II (WindObserver FC) is not in its final
location, it should be protected from damage by keeping it in the original
packaging as long as possible, treating it as a delicate instrument.
6.1. Installation Guidelines
The WindObserver II (WindObserver FC) has been designed to meet and exceed the
stringent standards listed in its specification. Operating in diverse environments all over
the world, WindObserver II (WindObserver FC) requires no calibration or adjustment
whatsoever.
As with any sophisticated electronics, good engineering practice should be followed to
ensure correct operation.
 Always check the installation to ensure the WindObserver II (WindObserver FC) is
not affected by other equipment operating locally, which may not conform to
current standards, e.g. radio/radar transmitters, boat engines, generators etc.
Guidelines –
 Avoid mounting in the plane of any radar scanner – a vertical separation of
at least 2m should be achieved.
 Radio transmitting antennas, the following minimum separations (all round)
are suggested
• VHF IMM – 1m
• MF/HF – 5m
• Satcom – 5m (avoid likely lines of sight)
 Ensure the product is correctly earthed in accordance with this manual
 Use cables recommended by Gill, keeping the length below the maximum allowed
(See Section 6.3) Where the cables are cut and re-connected (junction boxes, plugs
and sockets) the cable screen integrity must be maintained, to prevent the EMC
performance being compromised.
 Earth loops should not be created – earth the system in accordance with the
installation guidelines. (See Section 6.4)
 Ensure the power supply operates to the WindObserver II (WindObserver FC)
specification at all times.
Avoid turbulence caused by surrounding structures that will affect the accuracy of the
WindObserver II (WindObserver FC) such as trees, masts and buildings. The World
Meteorological Organisation makes the following recommendation:
 The standard exposure of wind instruments over level open terrain is 10m above
the ground. Open terrain is defined as an area where the distance between the
sensor and any obstruction is at least 10 times the height of the obstruction.

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6.2. Bench system test
Note: Prior to physically mounting the WindObserver II (WindObserver FC) in its final
location, we strongly recommend that a bench system test be carried out to confirm the
system is configured correctly, is fully functional and electrically compatible with the
selected host system and cabling (preferably utilising the final cable length). The required
data format, units, output rate, and other options should also all be configured at this
stage. If an Integrity Check Chamber (ICC) has been purchased refer to Section 9.6.
6.3. Cabling
Cable type
A RS422 compatible cable should be used, with the number of twisted pairs matching the
application.
Generic description – Twisted pairs with drain wire, screened with aluminised tape,
with an overall PVC sheath. Wire size 7/0.2mm (24 AWG)
The table shows some suitable manufacturers’ references; other manufacture’s equivalents
can be used.
Table 1
No. of pairs Gill ref. Belden
ref.
Batt electronics
ref.
2 - 9729 -
3 026-02660 9730 91030
4 026-03156 9728 91199
9 026-02663 8774 91009
Cable length
The typical maximum length at 9600 baud is 1km (3200ft), using the recommended cable.
If any problems of data corruption are experienced (due to, for example, a high local
electrical ‘noise’ level), then a lower baud rate should be used. Alternatively, a thicker or
higher specification cable can be tried. See also Section 6.1
Cabling and junction box
The WindObserver II (WindObserver FC) unit is fitted with a flying 9 pair cable attached
(15m long). This must be terminated in a suitable terminal box to IP66 or better, fitted
with glands to prevent moisture ingress.
The cable type from the terminal box to the host system must be as specified above. If any
cable is likely to be exposed to mechanical damage, it must be enclosed in a suitable
conduit or cable tray. The cable must be securely fixed with cable clamps or equivalent,
such that the cable is not under stress at the cable glands.
The gland area at the base of the WindObserver II (WindObserver FC) should not be
directly exposed to moisture, as whilst the gland is sealed when mated, the anemometer is
vented to air at the base to avoid pressure build up. If an IP66 rating is essential or the unit
is mounted other than ‘right way up’ use the gasket provided in the mounting kit.

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6.4. Connections
Important Do NOT join any of the cores of the cable together. Joining cores
could damage the unit permanently. Any cores not used should be isolated.
Do NOT connect the unit’s 0V, heating –ve or digital 0V to the screen or earth.
The screens of each pair are joined together inside the anemometer - these should be
joined to the cable screen(s) of any further cable run. Avoid long grounding loops. Digital
OV should be used in conjunction with RS422 TX RX lines in order to improve noise
immunity. Each pair in the cable is labelled with its pair number.
Table 2
Conductor colour Designation
Pair 1 green RS422_TXB (+)
black RS422_TXA (-)
Pair 2 white RS422_RXB (+)
black RS422_RXA (-)
Pair 3 red Supply V+
black Supply V-
Pair 4 blue Digital 0v
black Not used (isolate)
Pair 5 yellow Heater +
black Heater –
Pair 6 brown Not Used (isolate)
black Not Used (isolate)
Pair 7 orange Not Used (isolate)
black Not Used (isolate)
Pair 8 white Not Used (isolate)
red Not Used (isolate)
Pair 9 green Not Used (isolate)
red Not Used (isolate)
Screens Chassis ground
Earthing or grounding
To ensure correct operation, and for maximum protection against lightning, the
anemometer MUST be correctly earthed (grounded) via its mountings. Inadequate
Earthing will degrade anemometer performance, particularly in the presence of radio
frequency interference.
See Fig 1 Suggested mounting bracket and Earthing (grounding) arrangements
The unit MUST be connected to an appropriate grounding point with a minimum of 6mm²
copper wire, via the M5 base screws. The cable screens must be joined with any cable
screen continuing from the unit’s cable via a junction box. The primary earth for the
anemometer must be provided via the base screws and not via the cable screens.

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Default Settings
The factory default settings are:
A0 B3 C2 E1 F1 G0000 H2 J1 K1 L1 M5 NA O1 P1 T1 U1 V1 X1 Y1 Z6
See Section 8 Configuring for further details
Connecting to a PC with a RS422 or RS485 input
The PC requires either an internal RS422 interface card, or an external RS422/485 to
RS232 converter, which will plug into the standard 9 way or 25 way RS232 serial port of
the PC or host equipment.
WindObserver II
(WindObserver FC)
9 pair cable
PC with RS422 or
RS485 input
Signal names Pair
no. Colour Cable – 3 or 4 twisted pairs Signal names
TXB (+)
TXA (–) 1 green black RXB (+) RXA (–)
RXB (+)
RXA (-) 2 white black TXB (+) TXA (–)
Digital 0V 4 blue Signal Ground
CONNECTED INTERNALLY Screen and
drain wires Ground (Earth)
Supply V+
Supply V- 3 red black
+
-
DC Power
supply 20 – 30V
see Section 6.5
Heater +
Heater - 5 yellow black
+
-
Heater power
supply
See Section 6.5

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6.5. Power supplies
All WindObserver II (WindObserver FC) units
Voltage 20 to 30v DC
Current 60mA max. 50mA average
Heating
The heating module requires a separate power supply.
Either
22 – 30V DC @ 3A
or 24V AC RMS ±10% @ 3A AC RMS
NOTE: AC Supply must be isolated from Mains Supply
6.6. Mechanical installation
Before installing, a bench system test is recommended (see Section 6.2).
All the time the WindObserver II (WindObserver FC) is not in its final
location, it should be protected from damage by keeping it in the original
packaging as long as possible, treating it as a delicate instrument.
Location
It is important to ensure that the WindObserver II (WindObserver FC) is mounted in a
position clear of any structure, which may obstruct the airflow or induce turbulence.
Do NOT mount the WindObserver II (WindObserver FC) in close proximity of high-
powered radar or radio transmitters. A site survey may be required if there is any doubt
about the strength of external electrical noise. (See Section 6.1)
Orientation
Normally the WindObserver II (WindObserver FC) is mounted vertically with the cable
exit at the bottom.
Alternatively, the unit may be mounted in any orientation, but note that if the unit is
mounted with the cable uppermost, the gasket provided in the mounting kit must be used.
Mounting bracket
A suggested mounting bracket is shown in Fig 1 below.
It is recommended that the WindObserver II (WindObserver FC) mounting bracket is
manufactured from stainless steel 316, to prevent possible galvanic corrosion.
It is also recommended that the supplied gasket is always fitted to ensure IP66 rating and
to prevent galvanic corrosion if the mounting bracket is not manufactured from stainless
steel 316.
Stainless steel 316 fixings must be used.

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Figure 1. Suggested mounting bracket and Earthing (grounding) arrangements

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Alignment
The anemometer should be set to point North (or to another known reference direction),
using the North Spar, which can be identified from the alignment indicator on the base of
the instrument. See Figure 2a.
Figure 2a North marker and UV polarity definition (UV) format) and Mounting
Ring
See Fig. 3, on page 24 for U,V DEFINITION

Gill Instruments Ltd
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Figure 2b WindObserver II (WindObserver FC) Outline Dimensions.
15 Metre Cable
100 mm
long tails

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7. MESSAGE FORMATS & OPTIONS
On first applying power to the WindObserver II (WindObserver FC), it will be in
‘Measurement Mode’, and it will output wind measurement information in one of the
configurations as described below.
Setting the output format, units, other parameters, options and the communication settings
are all carried out in the alternative ‘Configuration Mode’.
See Section 8 CONFIGURING for details of how this is done.
The factory default settings are shown here in bold, and for convenience some
‘Configuration codes’ (as used to set the configuration) are shown in blue boxes.
For example M3.
7.1. Wind Speed format
The wind speed measurements can be output in one of the following formats:
UV, Polar, Customer format NMEA.
7.2. Output formats
The UV and Polar wind speed parameters are output in NMEA format. These parameters
can be transmitted continuously or polled from the user.
Polar is also available in continuous ASCII.
Output format Output Tri-state o/p Configuration code
Continuous No
M1
ASCII UV Polled Yes
M3
Continuous No M2
ASCII Polar Polled Yes M4
NMEA Continuous No M5
7.3. Units
The wind speed can be set to any of the following units:
Unit Abbreviation
Metres per sec m/s
Knots knots
Miles per hour MPH
Kilometres per hour kph
feet per minute fpm

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7.4. Output rate
The output frequency is set to1 per second. The wind speed is sampled every 25ms, each
axis being sampled sequentially. The following Table lists the possible outputs per second
and the corresponding number of averaged samples. A 25ms sample period is used to
process and output the results.
Outputs per Second Sample Average
1 39
7.5. Averaging
The Averaging Period can be set from zero to 3600 secs. (1 hour). The default setting is
zero. When averaging is enabled, data is output at a rate determined by the averaging
period. The data is an average of valid data collected during the averaging period.
7.6. Heating
Heating is autonomous and requires no set-up once activated.
7.7. 45°
°°
°Offset
The U axis is offset +45°to the transducer axis.
7.8 Vertical Output Padding
A dummy W vector is inserted to provide compatibility with any WindMaster that may be
in a network.

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7.7. ASCII message format (UV and Polar)
ASCII UV format
<STX>A,+000.04,-000.02,M,00,<ETX>25
Start of
String
Unit
Identification
U Axis Wind
Speed
V Axis
Wind
Speed
Units Status End
of
String
Check
Sum
Where
U axis wind speed In increments of 0.01 units (±UUU.UU)
V axis wind speed In increments of 0.01 units (±VVV.VV)
Value Units
Units M Metres per second (m/s)
N Knots (knots)
P Miles per hour (MPH)
K Kilometres per hour (kph)
F Feet per minute (fpm)
Start of string ASCII value 2
Unit identification Letter A – Z (default A)
Status Value Status
0 OK
60 Heating enabled and OK if enabled
Any other value Warning or fault condition
- see Section 9.5
End of string ASCII value 3
Check sum Exclusive OR of all characters between Start of String
and End of String reported as ASCII hex.

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ASCII Polar format
<STX>B,121,000.08,M,00,<ETX>06
Start of
String
Unit
Identification
Wind
Direction
Wind
Speed
Units Status End
of
String
Check
Sum
Where
Wind direction In degrees relative to N (DDD)
Wind speed In increments of 0.01 units (±MMM.MM)
All other parameters See Section 7.7 ASCII UV format

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7.8. NMEA Format
Instrument
Identifier
Wind direction Wind speed Units
Checksum
Delimiter
$ IIMWV, 120, R, 002.10, M, A* CC
Start of string Instrument
type
Wind
measurement
Status Check
sum
Where
Wind direction In degrees relative to N (DDD)
Wind speed In increments of 0.01 units (±MMM.MM)
Units M Metres per second (m/s)
N Knots (knots)
P Miles per hour (MPH)
K Kilometres per hour (kph)
F Feet per minute (fpm)
Start of string $
Instrument type IIMWV
Wind measurement R Relative wind measurement
Status A Valid measurement
V Invalid measurement
Check sum Exclusive OR of all characters between ‘$’ and ‘*’
reported as ASCII hex.
The default WindObserver II (WindObserver FC) configuration suitable for NMEA is:
B3, E1, F1, G0, K1, L1, M5, O1, P1, U1.
Consult specification NMEA 0183 version 3 (available on the web) www.nmea.org for
complete interface details.