NuAire LabGard D NU-543-400, Руководство пользователя

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OM0283 Page 53 of 70
Rev 2 July/2021
7.10.4 FlowGard ™ Control Board Reset
The FlowGard ™ control board has a reset function available for Qualified Service Personnel.
Master Reset
– Resets all calibration, cabinet size, motor type/function and option settings back to their default
condition. It is recommended to perform a master reset upon installation of replacement control board or if there
seems to be intermittent functional abnormalities.
Perform the following sequence to accomplish a master reset:
1) Turn off all functions i.e. blower, lights, etc.
2) Press and hold alarm silence key for 10 seconds until alarm LED flashes, then release.
3) Press hidden key within 5 seconds of the alarm LED flashing. There will be a (3) beep confirmation that
the reset has occurred.
4) Turn off cabinet (either unplug cabinet or use power switch on left side within control panel) then turn
back
on to reinitialize the FlowGard™ control board. Just as in the initial power up, the RED alarm LED will
blink to indicate power up status along with the display message of power on reset.
5) Press key to clear the power on reset message.
6) Enter into service parameters and input configuration, set points, calibration and option settings as
required.
7.11 Digital Intelliflow Airflow Sensor Description and Replacement
The airflow sensor function utilizes two thermistors that provide a constant current source. One thermistor is a
reference that uses a very low current source. The other thermistor is the airflow measurer that uses a very high
current source. As airflow passes over the thermistors, the airflow removes heat from the thermistor measuring
airflow. The loss of heat from the thermistor causes the voltage from the thermistor to increase. This increased
voltage subtracted from the reference thermistor output voltage is what directly relates to airflow velocity. A
repeatable curve can be generated (voltage vs. airflow velocity).
The thermistors used are glass bead and coated and can be cleaned by gently using a cotton swab and alcohol.
Formaldehyde gas, Hydrogen Peroxide and Chlorine Dioxide have no effect on the airflow sensors; however, the
formaldehyde/Ammonium bicarbonate residue that remains after decontamination should be removed from the
airflow sensor thermistors.
Disconnect electrical power from the cabinet before
attempting any maintenance action.
The airflow sensor is removed by turning the locking ring counterclockwise and gently pulling the sensor away
from the connector. To reattach the airflow sensor, turn sensor in keyed connector until key matches, push in and
turn the locking ring clockwise until ring locks.
Once the new sensor has been replaced, airflow calibration (sensor value adjust for inflow velocity) is required.
CAUTION
!
XX:XX
GAF3 Version XX:XX
Power on Reset