Page 14
Rain Collector II
C
ALIBRATION
OF
O
LDER
M
ODEL
W
EATHER
S
TATIONS
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.
