NuAire NU-5710, Руководство по эксплуатации и обслуживанию

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OM0249 Page 18 of 64
Rev 4 June/2020
Condensation on the glass door, walls, top, or bottom of the chamber indicates an incorrect balance of door and front
perimeter heat. Both the door and front perimeter heaters operate on a duty cycle. A good starting point for these duty
cycles is the default setting for the door & perimeter heaters in a room ambient temp of 22°C (72°F) at a temperature set
point of 37.0°C. The fresh airflow that the air pump delivers to the chamber has been preset at the factory. If condensation
starts forming on the sides or back wall in the chamber, the number and length of air injections into the chamber can be
increased. (See section 8.8.1.2 for instructions.) To alleviate the condensation, increase the airflow. To increase RH in the
chamber reduce the airflow. If airflow is decreased, some condensation may be unavoidable. The port plug with breather
hole must be used on the side port.
Humidity Monitoring and control system are available on Models NU-5720 and NU-5741.
These models humidify the chamber by circulating the chamber air through heated water vapor saturated air in a tank
located outside of the chamber. This gives the operator control over the amount of humidity in the chamber from an
ambient dependent low value to 95%. After a door opening, the recovery time to 90% +5% / -3% is 25 minutes on average.
The control system has a +3% accuracy from any given set-point 90% and below. Much of the information regarding the
water pan can be applied with the exception of the water pan.
The control system uses a solid-state capacitance humidity sensor to monitor the relative humidity within the chamber.
If humidity is required, the control system will activate a solenoid valve routing the chamber air through a humidified
heated enclosure just before being returned to the chamber. The control will continue rout the chamber air through the
water vapor saturated air until the set-point is achieved. Use only single distilled water, NO PURER THAN 1 MEGA OHM to
fill the reservoir. The relative humidity display and control option offers an accurate and reliable method to control
humidity when required. The alarm set-point defaults at 8% over the set-point and 3% below.
NOTE: DO NOT SEAL OR RESTRICT THE OPENING IN THE PORT PLUG.
THIS IS A PRESSURE RELIEF FOR THE CHAMBER.
8.3 Control System Introduction
The NuAire Incubator Control Electronics system is designed to serve the control requirements of the Incubator chamber.
Temperature, CO
2
levels in all models and RH & O
2
in available models are controlled by preset values to provide the
optimum conditions for culture growth within a chamber. Operator input is coordinated through the NuTouch LCD keypad
and status displays.
Figure 1 shows the various inputs and outputs of the system.
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