User`s Manual Model 6030 Optical Rain Gauge

Model 6030
Optical Rain Gauge
User’s
Manual
Rev. B
All Weather Inc. • 1165 National Drive • Sacramento, CA 95834 • USA • 800.824.5873 • www.allweatherinc.com
Copyright © 2011, All Weather, Inc.
All Rights Reserved. The information contained herein is proprietary and is provided solely for the purpose of
allowing customers to operate and/or service All Weather, Inc. manufactured equipment and is not to be released,
reproduced, or used for any other purpose without written permission of All Weather, Inc.
Throughout this manual, trademarked names might be used. Rather than put a trademark (™) symbol in every
occurrence of a trademarked name, we state herein that we are using the names only in an editorial fashion and to
the benefit of the trademark owner, and with no intention of infringement. All Weather, Inc. and the All Weather,
Inc. logo are trademarks of All Weather, Inc.
Disclaimer
The information and specifications described in this manual are subject to change without notice.
Latest Manual Version
For the latest version of this manual, see the Product Manuals page under Reference on our web site at
www.allweatherinc.com/.
All Weather, Inc.
1165 National Drive
Sacramento, CA 95834
Tel.: (916) 928-1000
Fax: (916) 928-1165
Contact Customer Service
•
Phone support is available from 8:00am - 4:30pm PT, Monday through Friday. Call 916-928-1000 and ask for
“Service.”
•
Online support is available by filling out a request at www.allweatherinc.com/customer/support.html
•
E-mail your support request to support@allweatherinc.com
Model 6030 Optical Rain Gauge
User’s Manual
Revision History
Revision
B
Date
2011 Oct 31
Summary of Changes
Removed references to OEM part numbers, replaced installation drawing with
diagrams in the Installation chapter, and better explained options and wiring details
Model 6030 Optical Rain Gauge
User’s Manual
TABLE OF CONTENTS
1. OVERVIEW .........................................................................................................................1 1.1 Accessories ................................................................................................................................ 1 2. SYSTEM DESCRIPTION ....................................................................................................2 2.1 Major Components .................................................................................................................... 2 2.1.1 Sensor Head ..................................................................................................................... 2 2.1.2 Electronics Enclosure....................................................................................................... 3 2.1.3 AC Interface Board .......................................................................................................... 3 3. THEORY OF OPERATION .................................................................................................4 3.1 Sensor Head ............................................................................................................................... 4 4. INSTALLATION ...................................................................................................................6 4.1 Siting and Installation Guidelines ............................................................................................. 6 4.2 Mechanical Installation ............................................................................................................. 8 4.2.1 Preparation ....................................................................................................................... 8 4.2.2 Mount the Sensor Head .................................................................................................... 9 4.2.3 Install the Electronics Enclosure .................................................................................... 11 4.3 Electrical Connections ............................................................................................................. 12 4.3.1 RS-485 Connections to the AWOS Data Collection Platform ...................................... 15 4.3.2 Connecting the Sensor to the AC Power Line ............................................................... 15 5. OPERATION WITH AN AWOS DATA COLLECTION PLATFORM .................................. 16 5.1 Sensor Interface ....................................................................................................................... 16 5.1.1 Physical Level ................................................................................................................ 16 5.1.2 Link Level ...................................................................................................................... 16 5.1.3 Frame Format ................................................................................................................. 16 5.1.4 Protocol .......................................................................................................................... 17 5.2 Data Format ............................................................................................................................. 18 5.2.1 Precipitation Codes ........................................................................................................ 18 5.2.2 Status Codes ................................................................................................................... 19 6. MAINTENANCE ................................................................................................................20 6.1 Triannual Maintenance ............................................................................................................ 20 7. SPECIFICATIONS ............................................................................................................22 8. WARRANTY ...................................................................................................................... 24 Model 6030 Optical Rain Gauge
User’s Manual
1. OVERVIEW
The Model 6030 Optical Rain Gauge optically measures precipitation-induced scintillation and
applies algorithms to determine the precipitation occurrence, type, rate, and water equivalent
accumulation automatically.
The Model 6030 Optical Rain Gauge measures precipitation by detecting the optical irregularities —
known as scintillations — induced by particles falling through a beam of partially coherent infrared
light in the sample volume. The induced scintillations are related to the characteristics to the precipitation, and the precipitation rate is determined based on the intensity of these scintillations. In turn, the
precipitation rate can be used to determine precipitation accumulation.
The Model 6030 Optical Rain Gauge is not affected by many of the environmental factors that cause
significant errors with traditional rain gauges. Model 6030 Optical Rain Gauge offers these features.
 Easy Installation
 Wide Dynamic Range
 High Sensitivity
 Works on Ships and Buoys
 Low Maintenance
 No Evaporation or Splash Errors
 Minimal Wind Effects
 Not Affected by Insects, Debris, Dust
Applications using traditional tipping bucket rain gauges can all be upgraded easily to use the Model
6030 Optical Rain Gauge.
The electro-optical design provides for an extremely reliable sensor with a calculated MTBF in excess
of 60,000 hours. Unlike mechanical gauges, which collect the precipitation to measure it, the Model
6030 Optical Rain Gauge has no collectors or buckets to corrode or clog. The sensors use automatic
gain control circuitry to eliminate the effects of LED output power or dirty optics. In fact, sensor
performance is maintained even when over 75% of the light is blocked! Diagnostics alert the user if
the signal strength is too low for normal operation. Preventative maintenance, suggested every 6
months, is as simple as cleaning the two optical windows on the unit.
1.1 ACCESSORIES
The following accessories and replacement parts are available for the Model 6030 Optical Rain Gauge.
Part Number
M488173-01
Description
Standalone Mounting Kit
M404806
Serial Sensor Interface Board
M442071
10 A 250 V, 5x20 mm slow blow fuse (F1—AC Interface
Board)
M442070
5 A 250 V, 5x20 mm slow blow fuse (F2—AC Interface
Board — used with 230 V setting)
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2. SYSTEM DESCRIPTION
2.1 MAJOR COMPONENTS
2.1.1 Sensor Head
The 6030 sensor head uses a compact optical system to measure precipitation.
The sensor head frame is an all-aluminum, welded design. The small box (TX) is the transmitter unit
and contains an infrared LED and lens with a disk heater. The large box (RX) contains a receiver
assembly consisting of a photo diode, a lens with an aperture slit, a disk heater, electronics, an
external thermistor probe, and a connector for the signal/power cable. The wiring between the two
heads is inside the welded head frame.
The transmit and receive lenses are heated by self-regulating positive temperature coefficient (PTC)
thermistor disks to a temperature above the ambient temperature to reduce dew and frost on the lenses.
Depending on the ambient temperature, the current drain for the lens heaters can change more than
200 mA.
The sensor head is completely sealed from water intrusion at the factory. Exercise care should to
avoid drilling or otherwise puncturing the frame.
A 15 m cable is supplied to connect the sensor head frame to the electronics enclosure.
A mounting plate, an integral part of the sensor head cross arm, is provided to install the head to a
user-supplied mast. Two sets of holes in the mounting plate allow the U-bolts supplied with the head
to clamp the head to either a vertical or horizontal pipe up to 50 mm in diameter.
N o t e:
The sensor head frame contains no user serviceable
parts - opening the head will void the warranty!
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2.1.2 Electronics Enclosure
The electronics enclosure contains the processing electronics, power supplies, and
surge protection circuits.
The electronics enclosure is a fiberglass NEMA-4X type box with a hinged access door. One power
supply, and AC and RS-485 interface modules with surge protection are mounted to the base plate of
the enclosure. Figure 9 shows the locations of these components inside the enclosure.
All the units in the enclosure are field-replaceable.
The electronics enclosure is mounted with the supplied fastener hardware using the four (4) mounting
holes on the enclosure.
N o t e:
Exercise care to avoid drilling or otherwise puncturing the
electronics enclosure.
2.1.3 AC Interface Board
Two fuses are located on the AC Interface Board (see Figure 1). Though installed, fuse F2 is not used.
Replace the fuses only with fuses of the same rating, as shown below.
F1
10 A 250 V, 5×20 mm slow blow
F2
5 A 250 V (not used)
Figure 1. AC Interface Board
Note that there is a plastic safety shield over the AC Interface Board. The fuses extend through holes
in the shield, and may be replaced without removing the shield.
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3. THEORY OF OPERATION
3.1 SENSOR HEAD
The sensor head is a self-contained unit consisting of electro-optical components,
heaters, a microprocessor, and integral cabling to connect with the electronics
enclosure.
The sensor measures precipitation by detecting the optical irregularities induced by particles falling
through a beam of partially coherent infrared light (in the sample volume). These irregularities are
known as scintillation. The twinkling of stars is a familiar example of scintillation. By detecting the
intensity of the scintillations which are characteristic of precipitation, the precipitation rate is
determined. Precipitation is measured using the sensor head “in-beam” optics.
Figure 2. Optical Rain Gauge Theory of Operation
The Model 6030 Optical Rain Gauge consists of these components.
•
A transmit modulator and infrared LED (TX)
•
A transmitter optical lens assembly
•
A receiver optical lens assembly
•
A photo detector and preamplifier (RX)
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
An Automatic Gain Controlled (AGC) normalizer

A signal processor

A temperature probe

A microprocessor and communications subsystem
The transmitter portion of the sensor head uses an infrared LED as a light source that is modulated to
eliminate interference in the system caused by background light. The LED has a very long life time,
has a relatively low power draw, is invisible to the eye, and presents no radiation hazard to the user.
The LED is housed in the smaller of the sensor head boxes. A lens is used to collimate the LED’s
carrier-wave modulated light into a slightly diverged beam. The transmit and receive lenses are both
heated by self-regulating positive temperature coefficient (PTC) thermistor disks to a temperature just
above the ambient temperature to reduce dew and frost on the lenses.
The larger sensor head rectangular box houses receive optics, DC regulator, the AGC, signal
processing electronics, temperature probe, and microprocessor. The receive lens focuses the
transmitted light onto a photo diode. The scintillations in light intensity are thus detected and
amplified. A wide dynamic range Automatic Gain Control (AGC) circuit normalizes the precipitationinduced scintillation signal to the carrier-wave modulated light. Thus errors from variations in the
source intensity caused by LED aging or dirt on the lenses are eliminated. The demodulated
scintillation signal is then further filtered, processed, and averaged. The statistical average of the
measured scintillation signals gives an accurate measurement of instantaneous precipitation rates.
The microprocessor uses an adaptive baseline technique to optimize the sensitivity of the Optical Rain
Gauge continuously. This technique ensures that the sensitivity is not affected by normal atmospheric
turbulence, and it minimizes the chance of false alarms (such as reporting precipitation when none
occurs). The processor uses the scintillation signal and temperature probe data to determine the
precipitation type and calculates the total water equivalent with the following formula.
mm
mm/h
h RR is the precipitation intensity, and k is a constant that depends on the ambient temperature, T, as
follows.
T > 3°C
T < =4°C
-4°C < T < 3°C
k=1
k = 0.607
exp
3
12
The microprocessor also provides diagnostic data about the condition of the sensor. The output is an
RS-232 data string that is converted to RS-485 by the Serial Sensor Processor in the electronics
enclosure.
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4. INSTALLATION
4.1 SITING AND INSTALLATION GUIDELINES
The Model 6030 Optical Rain Gauge may be installed almost anywhere outdoors. An
area free and clear of obstructions and contamination sources will help insure good
sensor performance.
In general, the sensor should be located on level or slightly sloping ground where the sensor site will
be exposed to the same environment as the area around it. Ideally, the area around the site should be
free of buildings, trees, and other obstructions.
All Weather, Inc. recommends that the siting and installation follow the general guidelines established
by the Office of the Federal Coordinator for Meteorology (OFCM). The Federal Standard for Siting
Meteorological Sensors at Airports, OFCM document # FSM-S4-1987, makes the following
recommendations.
1. Distance from Obstructions — The distance between the sensor and obstructions such as trees
or buildings should be at least 2 times the height of the obstruction on all sides. For example, if
a tree20 m high is located alongside the sensor, the sensor should be at least 40 m away from
the tree. This restriction reduces the effects of wind turbulence created by the nearby obstruction and makes the precipitation measurement more representative. Do not locate the sensor
where tree branches or wires will hang over the sensor!
2. Separation from Turbulence and Contamination Sources — Do not mount the sensor near
building exhaust vents, strobe lights, or sources of smoke or steam. Where possible, locate the
unit as far away from runways and roads as possible to reduce optics fouling from wind-blown
road dirt. An ideal minimum distance is at least 30 m.
3. Sensor Height, Rigidity, Verticality, and Orientation — The OFCM recommends that the
Optical Rain Gauge be mounted at a height of 10 ft (3 m). This height is not always possible
because of constraints imposed by the site. Mounting the sensor head lower than 2 m or higher
than 5 m is not generally recommended.
4. For AWOS installations, All Weather, Inc. recommends that the sensor head should be
mounted on a mast with a diameter of 50 mm (2") that is set in a concrete foundation is
recommended. The electronics enclosure should be nearby, keeping in mind that the cable
extending from the sensor head is 15 m long.
The installation must be rigid so that wind-induced vibration does not cause false alarms. This
can be accomplished by mounting the sensor to a thick wall pipe such as “Schedule 40” type
or to a rigid boom arm 1 m in length or shorter. The Optical Rain Gauge may be mounted on
the top of a building if it located near the center of the building away from the wind turbulence
that may occur near the edges.
The sensor head must be mounted vertical within ±2 degrees so that the line aperture on the inbeam lens is horizontal.
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5. The sensor head is generally oriented with the transmitter head on the north side (in the
Northern hemisphere) so that the receiver optics face north. Align the sensor head so that the
receive lens faces north. If the orientation can be altered to either side of north to obtain a
“view” with fewer or more distant obstructions, it is generally acceptable to alter the
orientation up to ±30 degrees from north.
SUGGESTION: Take a picture at the installation site in each direction (north, east,
south, and west) to record the topography and obstructions for future reference.
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4.2 MECHANICAL INSTALLATION
4.2.1 Preparation
The sensor and site should be readied prior to beginning the installation.
SITING GUIDELINES
 Sensor head mounted 2–5 m above ground
 Rigid mounting pole
 In-beam lens aperture horizontal to ±2 degrees
 Receiving (RX) lens facing away from sun (north in Northern Hemisphere)
 No overhanging trees, wires, or roof lines
 Distance between sensor and closest obstruction at least 2 times obstruction height
 As far from road, runway, and contamination sources as possible
The 6030 Optical Rain Gauge is packed in two heavy-walled corrugated cartons. One carton contains
the electronics enclosure and the larger, narrow carton contains the sensor head and cables. Also
packed in this carton are the sensor head U-bolt mounting hardware, and electronics enclosure
mounting hardware. When opening the cartons, be careful to avoid spilling the contents.
Report any shortages or shipping damage to All Weather Inc. within 3 days.
CAUTION!
Do NOT drill holes in any portion of the sensor head or electronics enclosure! Doing so will void
the warranty and may allow water to enter the enclosure!
Site Preparation
1. Choose the site using the guidelines in Section 4.2.1.
2. Following applicable electrical and building codes, install a concrete mounting base, mast or
tower, AC power cable, RS-485 signal cable, and ground rod.
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4.2.2 Mount the Sensor Head
The sensor must be securely installed and correctly oriented to work properly.
Figure 3. Mounting Sensor Head
1. Attach the sensor head using the two U-bolts to connect the mounting plate on the sensor head
and the mounting bracket with the ¼-20 hex locking nuts as shown in Figure 3. To mount the
head to a vertical mast or tower section, install the U-bolts and mounting bracket horizontally.
To mount to a horizontal tower section or boom arm, install them vertically using the same
holes.
Note that the metallurgy of the stainless U-bolts will cause the nuts to seize to the U-bolts and
twist them off. Lubricate the threads with anti-seize compound before assembling.
Do not tighten the nuts completely until the sensor head is installed on the mast or tower and is
oriented on the north-south axis as shown in Figure 4.
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2. Rotate the sensor head until the receive lens is facing north.
Figure 4. Sensor Head Orientation
When mounting the sensor head on a tower, choose the tower leg that gives the larger head an
unobstructed view to the North without rotating the head assembly into the tower. The head
assembly should be completely outside the tower as much as possible.
3. Tighten the U-bolt nuts when the orientation is correct. (Do not overtighten such that the
mounting plate is bent).
4. Use a large-diameter (8–12 AWG) ground wire to connect the ¼-20 ground stud on the bottom
of the sensor head to a copper-clad ground rod close to the base of the mast (see Figure 5).
5. Route the cables along the mast or tower to the electronics enclosure and secure them to the
mast or tower every meter using tie-wraps or other straps.
Figure 5. Installation of Ground Cable
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4.2.3 Install the Electronics Enclosure
One mounting kit option is available to mount the electronics enclosure.

Standalone Mounting Kit (AWI part number M488173-01)
Attach the electronics enclosure to the Unistrut brackets using the hardware supplied with the sensor.
Figure 6 shows the mounting arrangements.
Figure 6. Standalone Enclosure Mounting
Figure 7 shows the details of securing the mounting hardware.
Figure 7. Mounting Hardware Details
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These additional steps will help keep the mounting secure and corrosion-resistant.

Apply anti-seize compound to all external threaded connections.

Once the installation of the enclosure has been completed, apply a light spray of corrosion
block to all metallic connectors and threaded fasteners.
4.3 ELECTRICAL CONNECTIONS
Figure 8 shows the external connections at the bottom of the enclosure.

AC power conduit.

Signal cables from sensor head.

Serial connection to DCP.
AC POWER
CONDUIT
SERIAL CABLE
TO DCP
FROM
SENSOR HEAD
Figure 8. External Connections at Enclosure Bottom
Route the cable from the sensor head to the bottom of the electronics enclosure. Secure the cable to
the mast using tie-wraps or other straps.
1. Route the cable from the sensor head into the electronics enclosure as shown in Figure 8.
2. Connect the wires to the connector on the DIN rail shown in Figure 9 according to the wiring
diagram in Figure 10.
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Figure 9 shows the layout of the various electronics subassemblies inside the electronics enclosure.
SERIAL SENSOR
INTERFACE
J2
DC OUT
DC POWER
SUPPLY
J1
AC IN
H4
1234567
H1
5 4 3 2 1
115/230
EMI
FILTER
FUSE
ON
OFF
2
3
4
5
6
7 8
GND
F1
S1
FUSE
TB1
12 3
AC INTERFACE
BOARD
SENSOR
HEAD
DCP
Figure 9. Optical Rain Gauge Subassemblies Inside Enclosure
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Figure 10 summarizes all the signal and power wiring for the Model 6030 Optical Rain Gauge.
Sensor Interface Processor Board
TB1 Pin
Function
Color
4
RS-485 (+)
GREEN
5
RS-485 (–)
BROWN
6
GROUND
BLACK
7
DC +
RED
AC Interface Board
TB1 Pin
Function
Color
1
HOT
BLACK
2
NEUTRAL
WHITE
3
GROUND
GREEN
6030
OPTICAL
RAIN GAUGE
YEL
BLK
RED
BLK
BLU
BLK
GRN
BLK
RED
F1
DC + (2)
BLK
2
DC – (10)
3
4
5
6
7
DC – (9)
8
DC + (1)
DCP
RED
BLK
WHT
from
CONDUIT
FITTING
GND
WHT
BLK
1
RS-232(Tx)
RS-232(Rx)
RS-232(GND)
RS-485(+)
RS-485(–)
GND
DC INPUT(+)
RS-485–
RS-485+
RS-485–
RS-485+
TB2
3
2
1
2
3
4
5
6
7
GND
ON
CABLE
OFF
TB1
RED
WHT
BLK
GRN
BRN
BLK
RED
DC = AND DC – CONNECTIONS
REFER TO DC POWER SUPPLY
HEADER J2
TB4
10
9
8
7
6
5
4
3
2
1
SENSOR INTERFACE
PROCESSOR
M404802
POWER INTERFACE
BOARD
5
J1
4
5
4
3
2
1
3
2
1
BLU
BRN
M438210
POWER
SUPPLY
Figure 10. Optical Rain Gauge Signal and Power Wiring
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4.3.1 RS-485 Connections to the AWOS Data Collection Platform
RS-485 connections are made to the Serial Sensor Interface located in the upper right side of the
electronics enclosure. A 3-wire connection to the AWOS Data Collection Platform (DCP) is used.
Before proceeding, verify that the 6030 electrical power is turned “OFF.”
1. If the shielded RS-485 cable is not already connected to the DIN rail connector and the Serial
Interface Processor, connect the WHITE RS-485(+) signal cable to terminal 6, connect the
BLACK RS-485(–) signal cable to terminal 7, and connect the RED GND signal cable to
terminal 8 of the DIN rail terminal block.
2. Feed the free end of the shielded RS-485 cable through the serial cable gland shown in Figure 8.
3. Strip and tin the ends of the wires.
4. Route the cable through a cable gland on the DCP and connect the three wires inside the DCP
to TB4 pins 1 (WHITE), 2 (BLACK), and 7 (RED).
5. Ensure that none of the wires are stressed, then hand-tighten the gland seals on the DCP
enclosure and on the Model 6030 Optical Rain Gauge enclosure.
4.3.2 Connecting the Sensor to the AC Power Line
Connections are made to the AC interface module inside the electronics enclosure
AC power connections are made to the AC Interface Board located in the lower center of the
electronics enclosure. A 3-wire, single-phase AC source is required consisting of hot, neutral, and
earth ground connections.
WARNING
Turn off electrical power at the source before making the electrical connections to the
sensor!
1. Install a conduit fitting at the location shown in Figure 8. Feed the power cable through the
conduit fitting. A 3-wire 16 to 18 AWG cable is recommended.
2. Crimp fork type terminals to the ends of the wires.
3. Connect the three power cable wires to the AC Interface Board terminal blockTB1 pins 1
(LINE), 2 (NEUTRAL), and 3 (GND).
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5. OPERATION WITH AN AWOS DATA COLLECTION
PLATFORM
5.1 SENSOR INTERFACE
The Model 6030 Optical Rain Gauge responds to a poll from the DCP for the setup, operation, and
status of the sensor.
5.1.1 Physical Level
The serial signal output from the Serial Sensor Processor consists of a three-wire RS-485 connection.
5.1.2 Link Level
Data transfer across the interface is implemented via a serial, ASCII encoded, half duplex, 4800 bps,
asynchronous transfer link. Data transfer in the DCP-to-sensor direction is limited to a poll command
("PRWX00\r\n"). Data transfers in the sensor-to-DCP direction are fixed-format ASCII strings
terminated with a carriage return (<CR>).
5.1.3 Frame Format
The standard output frame format is shown below. Details of the data fields are presented in a later
section. Each of the transmitted characters are eight (8) bit (msb - bit 7 - always 0), no parity ASCII
(decimal codes 0 to 127), with 1 stop bit. The status code and other information, is formatted in this
way as printable ASCII characters to aid in system debugging and field maintenance.
The output message from the interface computer in response to the poll consists of the following
string of characters.
Position
Contents
Description
1
<blank><blank><equals sign>
start of message string
4
W_ _PppppSssss
W plus _ _ (no present weather codes)
P plus rain rate in four digits with floating-point
decimal (0.001 to 9999)
S plus four-digit status code (see Section 0)
17
<blank>
18
X000L000K000H000T000
38
<blank>
39
sensor crc error counter <blank> sensor
input msg counter
no engineering data displayed
<blank> 4-character CRC<cr><lf>
crc from position 4 up to but not including the
crc itself
no engineering data displayed
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5.1.4 Protocol
In order to keep the interface design effective and simple, the protocol does not support unsolicited
messages to the DCP. In other words, the only time the sensor is allowed to transmit a message to the
DCP via this link is in direct response to a poll transmission from the DCP, which requires the return
of the standard data reply string.
Note that the sensor is sampling data continually (every 5 seconds) and processing the precipitation
algorithm (once a minute typical). In most cases, the sensor’s response time to a poll will begin within
a second or two after receiving the poll, but the response time could be several seconds in unusual
circumstances. Avoid these hang-ups by waiting at least 10 seconds before timing out and trying
another poll.
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5.2 DATA FORMAT
The raw weather information from the sensor head is encoded in the reply message as follows.
Byte
Description
Value
1
2
3-4
5
6-9
10
11-14
15
16
17-19
20
21-23
24
25-27
28
29-31
32
33-35
36
Start of transmission
Weather type marker
Present weather field
Precipitation rate marker
Precipitation rate field
Status field marker
Status field
Blank
Carrier raw data field marker
Carrier 1 min average raw data
Low raw data field marker
Low 1 min average raw data
Particle raw data field marker
Particle 1 min average raw data
High raw data field marker
High 1 min average raw data
Temperature field marker
Temperature field
Blank
=
W
__
P
pppp
S
ssss
0x20
X
000
L
000
K
000
H
000
T
000
0x20
The various fixed fields used in the above poll response are explained here.
1. The capital letters “W”, “P”, “S”, “X”, “L”, “K”, “H”, and “T” above serve as place markers
for the Weather, Precipitation, Status, Carrier, Low, Particle, High, and Temperature data
fields to follow. These markers are fixed in position and coding. They are included within the
format to simplify manual interpretation of the sensor output.
2. No present weather data are reported by this sensor, so the field displays _ _.
3. pppp is a four-byte field indicating the precipitation rate.
4. The remaining fields have no data and display zeroes.
5.2.1 Precipitation Codes
The precipitation rate is reported as a 4-byte field with the number in a floating-point format, varying
from 0.001 to 9999. Zero is formatted as four zeros (“0000”). The units are millimeters/hour for the
rain rate averaged over a one-minute period.
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5.2.2 Status Codes
The status codes are a convenient way for the sensor to report the sensor condition.
The status field, denoted by s s s s (four bytes) in the data output format, is a four-byte field of sensor
status bytes. The codes can be interpreted as shown in the table below.
S
BYTE 10
BIT
0
STATUS
OK
BIT
0
1
STATUS
OK
Error
S S S S
11 12 13 14
BIT
0
STATUS
OK
BIT
0
STATUS
OK
A status code of 0 in bytes 11, 12, 13 or 14 indicates “no problem,” while a 1 for byte 12 means there
is a problem in the sensor head.
Example
Status codes read S0180. Interpret this code as follows.
Byte 11 = 0
Byte 12 = 1
Byte 13 = 0
Byte 14 = 0
OK
Error (Sensor Head probably bad)
OK
OK
Solution
Wait for 5 minutes to verify that the microprocessor resets. If the status code still reads S0100, replace
the Sensor Head and recheck the status code. After 5 minutes (when the microprocessor resets) the
status codes should now be S0000.
In normal operation (excluding the first five minutes after reset or power-up), the status bytes will be
all low (0000). The host system should take action to alert maintenance personnel of a possible
problem. In addition, data from the sensor will be disregarded and a “missing” report issued. (Note
that the sensor does not necessarily stop outputting data when a status bit flags an error condition.)
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Model 6030 Optical Rain Gauge
User’s Manual
6. MAINTENANCE
The Model 6030 Optical Rain Gauge is designed for high reliability and low operator maintenance.
The only scheduled maintenance is to periodically clean the lenses. In most locations, cleaning the
lenses every four months is recommended. Historically, the sensors have operated unattended for
several years without any degradation in performance. Use the table provided to record the
maintenance performed.
Equipment Required

Clean Cotton Cloth or Lens Tissue

Common Household Glass Cleaner
6.1 TRIANNUAL MAINTENANCE
1. Clean Lenses
Cleaning the lenses should be done with lint-free cloth and cleaning solution. Clean the lenses
by first spraying the lens cleaner on the lens and then wipe gently to prevent scratching the
glass optics. In actual practice, moderate dust buildup and scratches on the lenses will not have
any discernible effect on the instrument.
2. Check Lens Heaters
With a clean finger, touch the lenses in front of the disk-shaped heater that is bonded to the
lower inside surface of both lenses. The lens surfaces should be slightly warmer to the touch
than the ambient temperature.
3. Comb Test
Using a pocket comb, stroke it up and down vertically in front of the receiver lens as shown in
Figure 11 for ~1 minute. Do not block the beam for any length of time. Look at the data on the
DCP screen to make sure it varies as the comb is moved around.
Figure 11. Comb Test Illustration
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Model 6030 Optical Rain Gauge
User’s Manual
Maintenance Log
Date
Date
Clean Lenses
Verify Lens Heaters
Comb Test
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Date
Model 6030 Optical Rain Gauge
User’s Manual
7. SPECIFICATIONS
Parameter
Specification
Rain Dynamic Range
0.1 – 500 mm/h
Rain Accumulation
0.1–999,999 mm
Rain Accumulation Resolution
0.001 mm
Rain Accumulation Accuracy
5% of accumulation
Snow Dynamic Range
Snow Accumulation
0.01–50 mm/h water equivalent
0.001–999,999 mm water equivalent
Snow Accumulation Resolution
0.001 mm
Snow Accumulation Accuracy
10% of accumulation
Time Constant
10 s
Data Update Rate
Once per minute
Serial Output
RS-485
Output Format
ASCII characters
Baud Rate
Serial Port Parameter Setting
4800 bps
8-N-1 (8 data bits, no parity, 1 stop bit)
Power Requirements
Supply Voltage
Transient Protection
115/230 V AC, 50/60 Hz, 50 W
AC power and RS-485 signal lines fully protected
Environmental
Operating Temperature
-40 to +50ºC
(-40 to +122ºF)
Storage Temperature
-50 to +60ºC
(-58 to +140ºF)
Relative Humidity
0–100%, noncondensing
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Model 6030 Optical Rain Gauge
User’s Manual
Parameter
Specification
Mechanical
Controller Assembly Enclosure
NEMA 4X fiberglass
Sensor Assembly
Mounting
Controller
Assembly
Sensor Assembly
Dimensions
2.5" (6.35 cm) dia. mast
Unistrut mounted
11.5 cm H × 26.4 cm W × 73.0 cm D
(4.5" H × 10.4" W × 28.75"D )
Controller
Assembly
36 cm W × 41 cm H × 20 cm D
(14" W × 16" H × 8" D)
Sensor Assembly
4 kg (8.8 lb)
Controller
Assembly
10 kg (22 lb)
Shipping Weight (2 boxes)
16 kg (35 lb)
Weight
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Model 6030 Optical Rain Gauge
User’s Manual
8. WARRANTY
This equipment has been manufactured and will perform in accordance with requirements of FAA
Advisory Circular 150/5220-16B. Any defect in design, materials, or workmanship which may occur
during proper and normal use during a period of 1 year from date of installation or a maximum of 2
years from shipment will be corrected by repair or replacement by All Weather Inc.
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All Weather Inc.
1165 National Drive
Sacramento, CA 95818
Fax: 916.928.1165
Phone: 916.928.1000
Toll Free: 800.824.5873
6030-001
Revision B
December, 2011