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AB-6474
Maintenance
Since the temperature/humidity sensor is inspected and
calibrated for high accuracy at the factory before
shipment, no field calibration is necessary. Follow the
maintenance instructions below.
1) Periodic inspection
Determine the frequency of periodic inspection
depending on the amount of suspended dust and
other contaminants in the environment. Regulary
check the sensing accuracy and clean the cover.
2) Troubleshooting
If any problem occurs during operation, refer to the
following table for appropriate solutions.
Troubleshooting and Solution
Problems Check
items Solutions
•
No output
generated
•
Unstable output
•
Loose wiring
•
Disconnected
wiring
•
Power supply
voltage
•
Sensor damages
•
Re-perform wiring.
•
Replace sensor.
•
Slow response to
output
•
Moisture/conden-
sation on the
sensor
•
Remove cover.
•
Dry power-off
state sensor in
clean air
seasoning.
•
Error in output
•
Installed location
•
Dust and
contamination on
the sensor
•
Refer to
‘Installation
requirements’.
•
Clean the cover.
•
Perform humidity
single-point
calibration.
•
Replace the
sensor.
3) Humidity single-point calibration (Models HTY7043T,
HY7043T)
When you find an output error of the humidity sensor,
the sensor can be calibrated with the adjustment
knobs,VR1 for rough adjustment, VR2 for fine
adjustment, located inside the humidity sensor. The
output value is increased by turning these knobs
clockwise and decreased by turning them
counterclockwise.
Use a reliable measuring instrument for humidity
single-point calibration with correct procedure in
appropriate environment. A digital multimeter is
recommended to check the output voltage.
Fig. 20 Adjustment knobs arrangement on the circuit board
Cautions
1. Leave the unpacked sensor in the ambient
atmosphere for approx. 24 hours.
2. Be sure not to affect the sensor with heat generation
from human body and/or appliances during the sensor
calibration.
Building Systems Company
Tamachi Kiyota Building
4-3-4, Shibaura
Minato-ku, Tokyo 108-0023
http://www.yamatake.com
Rev. 2.1 Apr. 2005
AB-6474 0.5H-H (W00)
(J: AI-6474 Rev. 2.1)
Fine adjustment knob (VR1)
Temperature sensing
element
Humidity sensing element
Rough adjustment knob (VR2)
Specifications are subject to change without notice.
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