Davis Instruments Rain Collector II User manual

Rain Collector II
Installation manual
This instruction manual takes you step-by-step through the procedures required to
install the Rain Collector II. The Rain Collector II is designed for use with any of
Davis’ weather stations (with the exception of the Perception II® Station). Each station
can display rainfall in either inches or millimeters. Instructions for displaying rainfall
on the Weather Wizard III®and Weather Monitor II®are also included in this manual.
Components
The Rain Collector II includes the following components. Please make sure you have
all listed components before continuing.
•Rain Collector with Cable — The rain collector comes with the cone attached to the
base and has a 40’ (12m) cable.
•Four #8 x 3/4" Screws
•Debris Screen — This screen is placed into the rain collector cone to help prevent
debris from clogging the funnel hole.
•Metric Rain Adapter — This adapter adds weight to the tipping mechanism, adjusting
it to tip for every 0.2 mm of rainfall instead of every 0.01”.

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Rain Collector Internal Components
The illustration below shows the internal components of the rain collector, many of
which are referenced in this manual.
Rain Collector Internal Components

3
Tools and Materials Needed
You may need some of the following tools and materials to install the rain collector.
•Drill with 3/32" (2 mm) drill bit
•Medium Phillips Screwdriver
•3/16" (or 5 mm) Wrench
•Cable Clips or Weather-Resistant Cable Ties with screw holes or other means for mount-
ing
•Bubble Level (standard versions only)
Insert the Optional Metric Measurement Adapter
The rain collector tipping bucket mechanism contains a standard measurement weight
magnet that takes measurements in .01” for every tip of the bucket. The Weather Monitor
II assembly contains a metric measurement that adjusts the tipping bucket mechanism so
that it takes .2 mm metric measurements. To change the weight magnet:
1. Find the metric measurement adapter included in the hardware.
2. Locate the standard measurement weight magnet between the arms of the tipping
mechanism.
3. Open the arms slightly with one hand while pulling the magnet out with the other
hand.
4. Separate an end cap from one side of the magnet.
Open plastic tipping mechanism arms, pull out magnet

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5. Slide the magnet, with the exposed end of the magnet first, into the open slot of the
metric measurement adapter.
6. Insert the metric measurement adapter between the arms of the tipping bucket, with
solid side of the metric measurement facing up.
Although the rain collector is now ready to take accurate metric measurements, the
console does not register the rain collector measurement weight has changed. The rain
measurement type must be changed on the console.
Rainfall Calibration Number
Each station uses a rainfall calibration number (CAL) to determine how much water each
bucket tip (i.e., pulse) represents.
Calibrated Rainfall= Number of pulses x (1/CAL)
The default rainfall CAL of 100 works for the 0.01" rain collector. If you have a 0.01"
rain collector you do not need to adjust CAL at all.
Separate magnet from one end cap
Insert magnet with other end cap into metric measurement
adapter
Open plastic arms to insert metric measurement adapter,
with adapter in “V” position

Testing the Rain Collector II
5
If you install the metric adapter to your rain collector, first adjust the console to display
rainfall in millimeters and then change CAL to 0005. (To change CAL, press and hold the
RAIN button until CAL appears on the display. Consult the station manual, if necessary,
for further instructions.) Be aware that the console will revert to its default calibration
(i.e., inches) if it loses power.
Note: Make sure you display rainfall in the appropriate units of measure before changing CAL; otherwise you
will be setting the wrong calibration number. If, by mistake, you change CAL before switching to the
appropriate units, you can rectify the error by switching to the appropriate units and then entering the
appropriate CAL (for millimeters, 0005; for inches, 0100).
Once the console is calibrated for 0.01" (default) or 0.2 mm, you can switch the display
units as often as you like; the console accurately converts rainfall amounts regardless of
the type of rain collector you use.
Caution to Pre-1994 Station Owners
If you purchased a Monitor or Wizard station prior to 1994, it may be pre-calibrated for
an earlier model rain collector. See “Calibration of Older Model Weather Stations” on
page 9 for instructions.
Testing the Rain Collector II
Before installing the Rain Collector II, test the unit. If you are replacing a rain collector
you previously installed, make a note of the total rainfall amount displayed. You may
want to reenter this amount after you test the rain collector.
1. Turn the rain collector upside down and
remove the cone from the base by rotating
the base until the latches on the cone line up
with the latch openings in the base then
lifting the base away from the cone.
2. Carefully cut and remove the plastic tie
which holds the bucket in place during ship-
ping.
3. Attach the rain collector cable to the appro-
priate connector on the junction box.
4. Consult your station manual or system
installation manual.
5. Press the appropriate key on your console as
necessary to display daily rainfall.
6. Press UNITS if necessary to display rainfall
in the rain collector’s native unit of measure.
7. While watching the display on your console
to see if it changes, slowly tip the bucket until it drops to the opposite side. If the dis-
play does not change, you may be tipping the bucket too quickly. Try again, more
slowly this time.
Remove the Cone from the Base

Testing the Rain Collector II
6
If the rainfall amount displayed on the console increases by the expected increment
(either 0.01" or 0.2 mm) each time you tip the bucket, your rain collector is working
properly. If the display changes only after you tip the bucket several times, the rain
collector may be functioning correctly but you may have an older version of the
station console. See “Calibration of Older Model Weather Stations” on page 14 for
details.
Installing the Rain Collector II
Note: Climbing on your roof may be hazardous. If you are uneasy about installing your unit please have a qual-
ified professional complete the installation. Davis specifically disclaims any liability for injury or loss
resulting from the installation or use of the Rain Collector II.
Follow the instructions in this section to install your rain collector. Make sure you read
“Choosing a Location for the Rain Collector” on page 5 as it contains important informa-
tion concerning placement of the rain collector.
Typical Weather Monitor II Installation
The illustration below shows a typical rain collector installation for the Weather Wizard
III and Weather Monitor II.
Typical Installation

Testing the Rain Collector II
7
Choosing a Location for the Rain Collector
Keep the following in mind when choosing a location for your rain collector:
•You must mount the Rain Collector II on a level surface. To make sure the surface is
level, use a bubble level or pour water into the T-shaped leveling trough in the collector
base and observe the surface of the water to ensure that the collector is level.
•Be sure there is an unobstructed path for water runoff from the drain screens.
•The Rain Collector II contains a magnet-operated switch which may not operate cor-
rectly if you mount the rain collector on or near any object which attracts a magnet.
To install the rain collector on a sheet metal roof, insulate the unit by making a platform
out of wood. Mount the base of the rain collector at least 1"(4 cm) away from any steel
or iron surface and make sure the reed switch is at least 1" (4 cm) away from any steel or
iron objects (e.g., nails).
•Choose a location which is easily accessible for normal cleaning and is distant from
trees or other sources of heavy pollen or debris.
Installing the Rain Collector II
1. If you have not already done so, separate the cone from the base.
2. If necessary, disconnect the rain collector cable from the junction box.
3. Locate a suitable mounting surface, using the guidelines above.
4. Place the base on the mounting surface and mark the location of the four holes (the
base has eight to choose from) you will use to secure the base.
5. Make pilot holes using a 3/32" (2 mm) drill bit. You should make the pilot holes about
1/2" (12 mm) deep.
6. Fasten the base to the mounting
surface using the #8 x 3/4" screws
provided
7. Attach the rain collector cable to
the appropriate connector on the
junction box.
8. To be certain the rain collector is
functioning properly after installa-
tion, retest the unit as described
“Testing the Rain Collector II” on
page 2.
9. Once you are sure the unit is func-
tioning properly, place the cone
back onto the base by putting the
latches on the cone into the latch
openings in the base and rotating
the cone clockwise until the latches
“lock” into place.
Fasten Base to Mounting Surface

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8
As you reattach the cone, make sure to run the cable to the cable slot in the base, or the
cone will not fit snugly against the base.
10.Place the debris screen, points down, into the cone. The screen prevents large bits of
debris from blocking the funnel hole.
11.To prevent fraying or cutting of the cable where it is exposed to weather, it is impor-
tant that you secure it so it doesn’t whip about in the wind.
Use cable clips or weather resistant cable ties to secure the cable. Place clips or ties
approximately every 3 to 5 feet (1 to 1.6 m). Do not use metal staples or a staple gun
to secure cables. Metal staples—especially when installed with a staple gun—have a
tendency to cut the cables.
Extending Cable Runs
If the cable length supplied with the rain collector is not long enough for your purposes,
you may extend it. The maximum length of cable is 900 feet (270 m). Note that this
length represents the total length from the rain collector to the console, including any
length of cable from the junction box to the console. To extend the cable, purchase stan-
dard 4-Conductor Extension Cables from Davis and connect them to the existing rain col-
lector cable.
Adjusting the Rain Collector II
The Rain Collector II is calibrated at the factory so the
bucket tips (and records rainfall) for each 0.01" (or 0.2
mm if the metric adapter has been fitted) of rain. To adjust
the calibration slightly, use a 3/16" (or 5 mm) wrench to
rotate the adjustment screws which are located underneath
the bucket (see “Rain Collector Internal Components” on
page 2). The adjustment guide embossed in the platform
shows how far you must rotate both screws in turn to
effect a 1% and a 2% change. Moving the screws in the
positive (+) direction causes the bucket to tip more times
(i.e. give a larger count) for a given amount of water.
Note: Modify both adjustment screws by the same amount.
To check the accuracy of the rain collector, compare the Davis Rain Collector with a tube
type rain gauge. Use a rain gauge with an aperture of at least 4 inches. Any smaller and
the readings obtained may not be accurate. Place the tube type rain gauge directly next to
the Davis rain collector. Compare the totals on three storms. Based on this, develop an
average for how far off the reading are. Adjust the screws to fine tune the reading for the
next three storms if necessary.
Note: Do not compare rainfall readings to reading obtained from television, radio, newspapers, or neighbors
readings. Such readings are not located in your specific environment and therefore are not an accurate
measurement of the weather readings taking place in your surroundings. The rain collector is carefully
tested at the factory to conform to the specifications listed in the back of this manual.
Adjustment Guide

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Maintaining the Rain Collector II
For greatest accuracy, you should thoroughly clean the Rain Collector II at least once or
twice a year.
1. Disconnect the rain collector cable from the junction box.
2. Separate the cone from the base.
3. Use warm soapy water and a soft cloth to clean pollen, dirt, and other debris from the
cone, cone screens, and bucket.
4. Use a pipe cleaner to clear the funnel hole in the cone and the drain screens in the
base. When all parts are clean, rinse with clear water.
5. Reattach the cone and replace the screen.
6. Reconnect the rain collector cable to the junction box.
Using the Rainfall Function
The instructions below explain how to display rainfall on the Weather Wizard III and
Weather Monitor II.
To Display Rainfall
1. To display daily rainfall, press RAIN. The daily rainfall and the word RAIN display.
2. To display total rainfall, press RAIN again. The total rainfall and the words RAIN and
TOTAL appear on the display.
Total Rainfall
To Change the Unit of Measure
1. Press RAIN once or twice to select daily or total rainfall, as desired.
2. Press UNITS. The amount shown changes from inches to millimeters (or vice versa)
and the symbol in the display changes from IN to MM (or vice versa).
3. To return to the original unit of measure, press UNITS again.
Daily Rainfall

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10
To Clear Rainfall
Daily and total rainfall are independent of each other. You must clear each register
separately.
1. Press RAIN once or twice to select daily or total rainfall, as desired.
2. Press CLEAR and hold it down.
The display will flash several times and then the weather station clears rainfall.
Daily Rainfall Cleared
Note: Performing a “total clear” on the weather station does not clear rainfall.
To Set Total Rainfall
You may enter a total rainfall amount to represent any rainfall which accumulated before
you obtained the Rain Collector II:
1. Press RAIN once or twice to select total rainfall.
2. Use ENTER to set the total rainfall amount. See “Using the Enter Key” in the weather
station manual.
Calibration of Older Model Weather Stations
This information applies only to users of the Weather Wizard II-S, Weather Wizard III,
and Weather Monitor II manufactured prior to April, 1993. To check if your station meets
this criterion, press the RAIN button on the console. If, when set to inches, the display
reads 0.0 (rather than 0.00), you have an older model station.
Standard Setting
When using the 0.01” setting of the Rain Collector II with an older model station, note
that the station is pre-calibrated for an earlier model 0.1" rain collector. To re-calibrate
your station, first set the display to inches, then change CAL to 0100. (See “Rainfall Cal-
ibration Number” on page 2 and/or your station user’s manual for instructions on how to
change CAL.) Be aware that the console will revert to its default calibration (i.e., 0.1") if
it loses power.
Metric Setting
When using the 0.2 mm setting of the Rain Collector II with an older model station, note
that the station stores rainfall amounts in 0.2 mm increments but displays amounts
rounded to the nearest whole millimeter.
Note: Keep in mind when testing the rain collector with older weather stations that the display adds 1 mm for
each 5 tips of the bucket. Because the display rounds, however, the first change occurs after the bucket
tips 3 times (0.6 mm rounded to 1 mm).

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To calibrate your station for rounded millimeters, set the console to display rainfall in
millimeters and then change CAL to 0005. (See “Rainfall Calibration Number” on page 2
and/or your station user’s manual for instructions on how to change CAL.) Be aware that
the console will revert to its default calibration (i.e., 0.1") if it loses power.
If you want your station to display rainfall in tenths of a millimeter, you can “trick” it into
displaying in 0.2 mm increments. To “trick” the station, first display rainfall in INCHES
and then enter a CAL value of 0005. To display rainfall thereafter, leave the unit of mea-
sure set to inches. Even though the display will show IN on the right hand side, the value
will actually be in millimeters. Please note, however, that if you do employ this “trick”
the maximum total rainfall will be 999.8 mm, rather than 9999 mm.
Troubleshooting Guide
Before calling Technical Support (1-510-732-7814), carefully check the following trou-
bleshooting guide. You may be able to solve the problem yourself.
•Rainfall is not registering on the console or the console has a large error. Try the follow-
ing:
• Check the cable connections from the sensor to the console. Cable connections
account for a large portion of the potential problems. Connections should be firmly
seated in the jacks and plugged in straight. If you think a connection may be faulty,
try jiggling the cable while looking at the display. If a reading appears intermittently
on the display as you jiggle the cable, the connection is faulty.
• Make sure there is no magnetic, steel, or iron object near the rain collector.
• Make sure the funnel hole in the cone is clear so water can empty into the bucket.
• Make sure the bucket moves freely when tipping to both sides. The console should
show an increase in rainfall for each tip of the bucket. (If the bucket does not move
at all, check that you have cut the cable tie that holds it in place during shipping.)
• Make sure the console is calibrated correctly by setting the console to your unit
preference before viewing or changing the CAL value (to 0100 for inches, to 0005
for millimeters). If this does not correct the problem, see “Calibration of Older
Model Weather Stations” on page 14 to determine if your station is an older model
station that warrants re-calibration.
• The console will revert to its default calibration if it loses power. You will need to
re-calibrate on power up if you have an older model station or a 0.2 mm rain collec-
tor.
•Rainfall amount shown on console has a small error.
• Make sure the rain collector is mounted on a level surface. Use the adjustment
screws (see “Adjusting the Rain Collector II” on page 11) to adjust the rain collec-
tor’s sensitivity, if necessary.
• If you believe the rain collector to be installed and calibrated correctly and you still
detect a small error, you can tweak the console’s calibration. Use the rainfall cali-
bration equation on page 3 to adjust the calibration number. (Note: Tweaking will
only work with the 0.01" rain collector; the calibration number for millimeters (5) is
too small to be tweaked precisely.)

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Contacting Davis Technical Support
If you have any questions, or encounter problems installing or operating your Vantage
Pro2 weather station, please contact Davis Technical Support. We’ll be glad to help.
[phone] — Monday - Friday, 7:00 a.m. - 5:30 p.m. Pacific Time. Sorry, we are
unable to accept collect calls.
[phone] (fax)— Technical Support.
[email protected] — E-mail to Technical Support.
[email protected] — General e-mail.
www.davisnet.com — Davis Instruments web site. See the Weather Support section for
copies of user manuals, product specifications, application notes, and information on
software updates. Watch for FAQs and other updates.

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Specifications
General
Sensor Type . . . . . . . . . . . . . . . . . . . . . . . . . .Tipping bucket with magnetic reed switch
Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Contact closure
Attached Cable Length. . . . . . . . . . . . . . . . . .40’ (12 m)
Cable Type . . . . . . . . . . . . . . . . . . . . . . . . . . .4-conductor, 26 AWG
Connector. . . . . . . . . . . . . . . . . . . . . . . . . . . .Modular connector (RJ-11)
Recommended Maximum Cable Length . . . .900’ (270 m)
Housing Material. . . . . . . . . . . . . . . . . . . . . . .UV-stabilized ABS plastic
Dimensions
Rain Collector . . . . . . . . . . . . . . . . . . . .8.75" diameter x 9.5" high (16.5 cm diameter
x 24 cm high)
Collection Area . . . . . . . . . . . . . . . . . . .33.2 in2(214 cm2)
Weight. . . . . . . . . . . . . . . . . . . . . . . . . .2 lbs. 3 oz. (1 kg)
Console Data
These specifications apply to sensor output as converted by Davis Instruments weather
station consoles.
Weather Monitor/Wizard Range
Daily Rainfall. . . . . . . . . . . . . . . . . . . . .0.00” to 99.99” (0.0 mm to 999.8 mm)
Total Rainfall . . . . . . . . . . . . . . . . . . . . .0.00” to 99.99” (0.0 mm to 9999 mm)
Accuracy
Rainfall . . . . . . . . . . . . . . . . . . . . . . . . .±4%, ±1 rainfall count between 0.01" and
2.00" per hour (0.2 mm and 50.0 mm per
hour); ±5%, ±1 rainfall count between 2.00"
and 4.00" per hour (50.0 mm and 100.0 mm
per hour)
Resolution. . . . . . . . . . . . . . . . . . . . . . .0.01” (0.2 mm)
Sample and Display Update Interval. . .16 seconds (max)
WeatherLink®Data
These specifications apply to sensor output as logged and displayed by the WeatherLink.
Daily Rainfall. . . . . . . . . . . . . . . . . . . . . . . . . .Total during archive interval
Total Rainfall . . . . . . . . . . . . . . . . . . . . . . . . . .Total during archive interval
Rate of Rainfall . . . . . . . . . . . . . . . . . . . . . . . .Maximum value during archive interval (For
Vantage Pro and Pro2 models only)
Input/Output Connections
Black & Red . . . . . . . . . . . . . . . . . . . . . . . . . .Switch terminal
Green & Yellow. . . . . . . . . . . . . . . . . . . . . . . .Switch terminal

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Notes

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Notes

Product Number: 7852 Part Number: 07395.224
Rain Collector II Rev B Manual (10/21/05)
This product complies with the essential protection requirements of the EC EMC Directive 89/336/EC.
Copyright © 2004 Davis Instruments Corp. All rights reserved.
3465 Diablo Avenue, Hayward, CA 94545-2778 U.S.A.
510-732-9229 • Fax: [phone]
E-mail: [email protected] • www.davisnet.com
Notes