Davis Instruments Rain Collector User manual

Product#7852,7852M,7856,7856M
R
AIN
C
OLLECTOR
II
S TANDARD AND I NDUSTRIAL
I
NSTALLATION
M
ANUAL
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. For
greatest accuracy, however, use a rain collector which measures in the same
unit in which you wish to display rainfall.
Instructions for displaying rainfall on the Weather Wizard II-S
®
, Weather Wiz-
ard III
®
, and Weather Monitor II
®
are also included in this manual. Instructions
for displaying rainfall on the GroWeather™, Health EnviroMonitor™, and
Energy EnviroMonitor™ are contained in the station’s user’s manual.
C
OMPONENTS
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. The standard
version of the rain collector comes with a 40’ (12 m) cable. The industrial
version comes with a 16’ (5 m) 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.

Page2 RainCollectorII
Rain Collector Internal Components
The illustration below shows the internal components of the rain collector,
many of which are referenced in this manual. Note that the industrial versions
of the rain collector also include a terminal block to which the rain collector
cable is connected and a bubble level to help you insure that the rain collector
is mounted on a level surface. Neither is pictured below.
R
AIN
C
OLLECTOR
I
NTERNAL
C
OMPONENTS

ToolsandMaterialsNeeded Page3
T
OOLS AND
M
ATERIALS
N
EEDED
You may need some of the following tools and materials in order 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
mounting
✦
Bubble Level (standard versions only)
R
AINFALL
C
ALIBRATION
N
UMBER
Each station uses a rainfall calibration number (CAL) to determine how much
water each bucket tip (i.e., pulse) represents.
CalibratedRainfall=Numberofpulsesx(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.
If you have a 0.2 mm 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; other-
wise 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 14 for instructions.

Page4 RainCollectorII
T
ESTING THE
R
AIN
C
OLLECTOR
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 dis-
played. 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.
R
EMOVE THE
C
ONE FROM THE
B
ASE
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 appropriate connector on the junction box/sen-
sor interface module (SIM).
Consult your station manual or system installation manual.
4. Press the appropriate key on your console as necessary to display daily rainfall.
Press UNITS if necessary to display rainfall in the rain collector’s native unit
of measure.
5. 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 display does not change, you may be tipping
the bucket too quickly. Try again, more slowly this time.
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.

InstallingtheRainCollectorII Page5
I
NSTALLING THE
R
AIN
C
OLLECTOR
II
Follow the instructions below to install the Rain Collector II.
CAUTION: Climbing on your roof may be hazardous. If you are uneasy about installing your unit please
have a qualified professional complete the installation. Davis specifically disclaims any liabil-
ity 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 see “Choosing a Location for the Rain Collector” on page 8 as it con-
tains important information concerning placement of the rain collector.
Typical Weather Wizard II-S, Weather Wizard III, or Weather Monitor II
Installation
The illustration below shows a typical rain collector installation for the
Weather Wizard II-S, Weather Wizard III, or Weather Monitor II.
T
YPICAL
I
NSTALLATION

Page6 RainCollectorII
Typical Standard GroWeather/EnviroMonitor Installation
The illustration below shows a typical standard rain collector installation for
the GroWeather, Energy EnviroMonitor, or the Health EnviroMonitor. The rain
collector cable attaches to connector S1 on the sensor interface module (SIM).
T
YPICAL
S
TANDARD
G
RO
W
EATHER
/E
NVIRO
M
ONITOR
I
NSTALLATION

InstallingtheRainCollectorII Page7
Typical Industrial GroWeather/EnviroMonitor Installation
The illustration below shows a typical industrial rain collector installation for
the GroWeather, Energy EnviroMonitor, or the Health EnviroMonitor. The rain
collector cable attaches to connector S1 on the sensor interface module (SIM).
T
YPICAL
I
NDUSTRIAL
G
RO
W
EATHER
/E
NVIRO
M
ONITOR
I
NSTALLATION

Page8 RainCollectorII
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 base and observe the surface of the
water. Users of the industrial rain collector may use the bubble level
attached to the base to insure that the mounting surface 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
correctly 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/SIM.
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.

InstallingtheRainCollectorII Page9
6. Fasten the base to the mounting surface using the #8 x 3/4" screws provided.
F ASTEN B ASE TO M OUNTING S URFACE
7. Attach the rain collector cable to the appropriate connector on the junction box/SIM.
8. To be certain the rain collector is functioning properly after installation, retest the
unit as described “Testing the Rain Collector II” on page 4.
9. Once you are sure the unit is functioning 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.
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 anemometer cable where it is exposed to weather,
it is important 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.

Page10 RainCollectorII
E
XTENDING
C
ABLE
R
UNS
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/SIM to the con-
sole.
✦
Standard Rain Collector
Obtain Standard 4-Conductor Extension Cables from Davis and connect
them to the existing rain collector cable.
✦
Industrial Rain Collector
Obtain the desired length of Shielded 2-Twisted Pair Extension Cables
from Davis. You may splice the extension cable to the existing rain col-
lector cable, or you may remove the rain collector cable from the termi-
nal block (and the cable clamp which secures it in place) and connect the
extension cable to the terminal block in its place. You will need to obtain
Shielded 2-Twisted Pair cable (available from Davis) or 1-pair cable else-
where. If using the Shielded 2-Twisted Pair cable, twist the red and white
wires together for use as one wire and twist the two black wires together
for use as the other wire. Note that it does not matter which wire goes to
each screw as long as only one wire goes to each screw. Make sure you
secure the extension cable in place using the cable clamp.
R
EPLACING
I
NDUSTRIAL
C
ABLE

AdjustingtheRainCollectorII Page11
A
DJUSTING THE
R
AIN
C
OLLECTOR
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) 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.
A
DJUSTMENT
G
UIDE
Note: Modify both adjustment screws by the same amount.
M
AINTAINING THE
R
AIN
C
OLLECTOR
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/SIM.
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.
5. When all parts are clean, rinse with clear water.
6. Reattach the cone and replace the screen.
7. Reconnect the rain collector cable to the junction box/SIM.

Page12 RainCollectorII
U
SING THE RAINFALL FUNCTION
The instructions below explain how to display rainfall on the Weather
Wizard II-S, Weather Wizard III, and Weather Monitor II. Instructions for dis-
playing rainfall on the GroWeather, Energy EnviroMonitor, and
Health EnviroMonitor are contained in the station’s user’s manuals.
To Display Rainfall
1. To display daily rainfall, press RAIN.
The daily rainfall and the word RAIN appear on the display.
DAILY RAINFALL
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
3. Press RAIN once or twice to select daily or total rainfall, as desired.
4. 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).
5. To return to the original unit of measure, press UNITS again.

UsingtheRainfallFunction Page13
To Clear Rainfall
Daily and total rainfall are independent of each other. You must clear each reg-
ister 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 rain-
fall.
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 accumu-
lated 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.

Page14 RainCollectorII
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.
0.01" Rain Collector II
When using the 0.01" 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 Calibration Number” on page 3 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.
0.2 mm Rain Collector II
When using the 0.2 mm 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).
To calibrate your station for rounded millimeters, set the console to display
rainfall in millimeters and then change CAL to 0005. (See “Rainfall Calibra-
tion Number” on page 3 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 dis-
play rainfall in INCHES and then enter a CAL value of 0005. To display rainfall
thereafter, leave the unit of measure 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.

TroubleshootingGuide Page15
TROUBLESHOOTING GUIDE
Before calling Technical Support (1-510-732-7814), carefully check the following
troubleshooting 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 following:
✦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 intermit-
tently 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 col-
lector.
✦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 CALvalue (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 collector.
✦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 collector’s sensitivity, if necessary.
✦If you believe the rain collector to be installed and calibrated cor-
rectly and you still detect a small error, you can tweak the console’s
calibration. Use the rainfall calibration 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.)

Product Numbers: 7852, 7852M, 7856, 7856M
Davis Instruments Part Number: 7395-024
Rain Collector, Standard & Industrial
Rev. C Manual (7/7/99)
This product complies with the essential protection requirements of the EC EMC
Directive 89/336/EC.
© Davis Instruments Corp. 1996. All rights reserved.