CSZ EZT-570S, Руководство пользователя

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EZT-570S User Manual
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that this condition is present. If your chamber is not obtaining the desired humidity level, check the
status monitor to verify that you are not trying to operate the chamber at a point outside of the
chamber’s minimum dewpoint capability.
Maximum Humidity Limitations
Certain chambers have limitations on the maximum humidity level that they can operate at a given
temperature in order to protect the chamber structure. This limit typically applies to modular
chambers. These chambers are constructed of individual panels that lock together to form the
chamber. The panels have an inner chamber liner and outer skin with a foam insulation sandwiched
between them. They are primarily used for large walk-in/drive-in chambers. Due to the materials
used in the construction of the modular panels, the humidity is typically limited to a maximum 70°C
dewpoint which corresponds to a maximum of 95% at 70°C (158°F).
When humidity is limited due to the fact that the maximum dewpoint has been achieved, the
corresponding system status Monitor indicator (RH HI DEWPOINT LIMIT) will illuminate to indicate
that this condition is present. If your chamber is not obtaining the desired humidity level, check the
status monitor to verify that you are not trying to operate the chamber at a point outside of the
chamber’s maximum dewpoint capability.
3.2.1.2 Auxiliary Cooling Operation
The auxiliary cooling system utilizes LN2 or CO2 as a boost cooling medium to assist the refrigeration
system in lowering the chamber air temperature. It is an inexpensive method for fast cooling
transitions without having to make the investment in a high horsepower refrigeration system that may
rarely be used. It can also be used as the primary cooling source for ultra-low temperature operation
on chambers designed to operate at temperatures below -84°C (-120°F)
When this option is installed on the chamber, turn the “Aux Cooling” event on. When the boost is
required during a pull down, the EZT-570S will automatically turn on the boost cooling solenoids and
inject LN2 or CO2, into the chamber to rapidly drop the temperature as required. Once the desired
set point is achieved, the boost solenoids will close in order to conserve LN2 or CO2 since it is no
longer required, and allow the refrigeration system to maintain the chamber air temperature.
If the chamber is designed for ultra-low temperature operation, and the set point is below the
minimum achievable temperature for the refrigeration system, the EZT-570S will disable the
refrigeration system and use the boost cooling system for the primary cooling source. This
automatically protects the refrigeration system from damage and optimizes system operation.
If the auxiliary cooling event is turned off, the only means of cooling will be from the refrigeration
system. If the set point is below the capabilities of the refrigeration system on an ultra-low
temperature chamber, the chamber will not be able to reach set point until the event is turned on.