Version 1.3
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to calibration.
3.
Outdoor Humidity Calibration
. Press the
SET
button again and the outdoor humidity value
will begin flashing. Press the
+
button or
MIN/MAX
button to adjust the humidity value to
the calibrated value.
Discussion
: Humidity is a difficult parameter to measure electronically and drifts over
time due to contamination. In addition, location has an adverse affect on humidity readings
(installation over dirt vs. lawn for example).
Official stations recalibrate or replace humidity sensors on a yearly basis. Due to
manufacturing tolerances, the humidity is accurate to ± 5%. To improve this accuracy, the
indoor and outdoor humidity can be calibrated using an accurate source, such as a sling
psychrometer or one step humidpak calibration kits (reference Section 11).
4.
Outdoor Temperature Calibration
. Press the
SET
button again and the outdoor
temperature value will begin flashing. Press the
+
button or
MIN/MAX
button to adjust the
temperature value to the calibrated value.
Discussion
:
Temperature errors can occur when a sensor is placed too close to a heat
source (such as a building structure, the ground or trees).
To calibrate temperature, we recommend a mercury or red spirit (fluid) thermometer. Bi-metal
(dial) and other digital thermometers are not a good source and have their own margin of error.
Using a local weather station in your area is also a poor source due to changes in location,
timing (airport weather stations are only updated once per hour) and possible calibration
errors (many official weather stations are not properly installed and calibrated).
Place the sensor in a shaded, controlled environment next to the fluid thermometer, and allow
the sensor to stabilize for 48 hours. Compare this temperature to the fluid thermometer and
adjust the console to match the fluid thermometer.
5.
Indoor Humidity Calibration
. Press the
SET
button again and the indoor humidity value
will begin flashing. Press the
+
button or
MIN/MAX
button to adjust the humidity value to
the calibrated value.
6.
Indoor Temperature Calibration
. Press the
SET
button again and the indoor temperature
value will begin flashing. Press the
+
button or
MIN/MAX
button to adjust the temperature
value to the calibrated value.
Press the
SET
button to exit the SET mode.
5.6
History Mode
The history mode allows you to review historical data for the last 24 hours in 3 hour increments.
To enter the history mode from the normal mode, press (do not hold) the
HISTORY
button. The
backlight turns on and the console beeps. The
HIS
icon will be displayed. Press the
MIN/MAX
button to review records in increments of -3 hours, -6 hours, -9 hours, -12 hours, -15 hours, -18 hours,
