CSZ EZT-570S, Руководство пользователя

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EZT-570S User Manual
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As altitude increases, the air density within the chamber decreases. The heating and cooling
systems require a minimum amount of air flow in order to operate correctly and control the internal
chamber air temperature. The altitude system will inhibit the operation of the heating and cooling
systems when the altitude increases beyond the design limits. This limit is typically around 65Kft.
Humidity Control Limitations
On most altitude chambers with the humidity system option, operation of the humidity system is
inhibited when the altitude system is enabled. The vacuum system used to control the internal
chamber pressure, cannot operate with the addition of moisture. Only altitude chambers with vacuum
systems specifically designed to operate with the presence of moisture will allow humidity control with
the altitude system enabled.
Unless the vacuum system was specifically designed to operate in conjunction with
humidity, the chamber must be dried out before entering into altitude operation. Any
standing water in the chamber must be eliminated or possible damage and premature
failure of the vacuum pump may occur.
3.2.2.2 Thermal Shock Transfer Mechanism Operation
For chambers designed to perform specific thermal shock testing, a transfer cart/basket is used to
shuttle the product under test between different extreme environments. The transfer mechanism
typically transfers between two or three different zones.
The location for the shuttle to transfer to is set by two or three events which describe the desired
location. Vertical thermal shock (VTS) chambers typically operate with a hot and a cold chamber.
The events then relate to these locations as “XFR HOT” or “XFR COLD”. Double duty thermal shock
(DTS) chambers, also shuttle product between hot and cold chambers; however, these chambers are
equipped with a center cold chamber and two outer hot chambers. Since DTS chambers shuttle
product from left to right and vice versa, the events describe the transfer positions as “XFR LEFT”
and “XFR RIGHT”. Liquid bath thermal shock (TSB) chambers typically include a third position which
is an ambient zone. The “ambient” zone removes the basket from the liquid baths and allows the
operator to load product into the basket. This position uses the “UNLOAD” event.
When a position event is selected, the other event(s) will be automatically turned off and the basket
will transfer to the selected location. If there is a failure in the mechanism and the basket does not
reach its intended position, the “TRANSFER ERROR” alarm will indicate this fault. The selected
transfer event will then be turned off automatically, and the transfer mechanism will not try to transfer
the shuttle again until the operator enters a new position selection.
Manual Transfer Selection
When operating thermal shock chambers, the typical operation involves transferring product from a
“hot side” to a “cold side”. Since the transfer event selections work like “radio buttons”, that is when
one is pressed the other turns off, you can use this for repetitive manual transfers without having to
select and deselect the different events.
For example, if you set the “User State” to “ON” for both the transfer hot and transfer cold events,
each time the update button is pressed, the selected position for the transfer mechanism will alternate
back and forth between the hot and cold chambers.
Automatic Program Transfer Selection
When running a ramp/soak program, only one transfer position should be selected in a step. In most
cases, since the object of the test is to cycle between two chambers with fixed temperature
conditions, a two or three step program is all that is required. Each step will have the same set
points, but the transfer cart position events will alternate between the two steps.