i3070series6_Site_Preparation+11-12.3.pdf.pdf - 第31页
Environmental Requirements 5 Site Preparation 5-3 Air Temperature Requirements Ta b l e 5 - 1 summarizes the temperatur e and co oling r equir ements for the system. Air Temperature Specifications The i3070 test system i…
5-2 Site Preparation
5 Environmental Requirements
Air Quality Requirements
As a rule, good air quality is as important for the reliability of your i3070 test system
as it is for your production process. Three types of airborne contaminants are
discussed below. The presence of any of these contaminants at the site will
contribute to system degradation, resulting in lower reliability and higher operating
costs.
Corrosive Contaminants
Corrosion is a complex form of material deterioration or destruction by chemical or
electrochemical reaction. The presence of corrosive contaminants (gases) in the
atmosphere is very common in industrial environments. If ignored, corrosion can
eventually degrade system performance by its effects on high impedance circuits
and low impedance interfaces. It can also deteriorate most plastics including
software storage media. The effects of corrosive contaminants are usually
accelerated at high humidities or high temperatures.
Corrosives generally cannot be filtered out of the air by normal filtration methods,
and the techniques that must be used for their removal are complex and costly. If
the source of corrosive contaminants cannot be eliminated, the system should be
installed in an enclosed environment with a fresh air supply at positive pressure.
Particulate Contaminants
Particulate contaminants (hard particles) consist of smoke, dust, hair, lint, fibers
and miscellaneous organic and inorganic materials. The presence of these
contaminants in the air can cause system degradation, especially where disk drives,
test fixtures, and low impedance interfaces are concerned. Particulate
contaminants can be filtered from the air, and appropriate filters should be included
with any air conditioning installation. Also consider installing “No Smoking” signs
in the area. Tobacco smoke is a well-known factor in fixture contact contamination.
It causes false failures leading to unnecessary DUT repairs and higher production
costs.
Viscid Contaminants
Viscid contaminants are oily or sticky airborne substances that can be deposited on
the system’s electronic and mechanical parts. Besides contributing directly to
system degradation, viscid contaminants collect and hold particulate contaminants
and make cleaning very difficult. Viscid contaminants can be removed from the air
by filtration, but the elimination of their source, if possible, is preferable.
Environmental Requirements 5
Site Preparation 5-3
Air Temperature Requirements
Table 5-1 summarizes the temperature and cooling requirements for the system.
Air Temperature Specifications
The i3070 test system is designed to operate uninterrupted in an area where the air
temperature is stable and in the range from 0°C to 40°C (32°F to 104°F), as
measured at the tester-to-fixture interface.
The system has a built-in temperature sensor inside the testhead, located on the
ASRU card. This sensor constantly monitors the temperature of the air that has
been drawn through the testhead after it cools the system components. If the
temperature sensor finds that the air temperature inside the testhead has changed
±5°C (±9°F) since the last time the system ran AutoAdjust All, it will run AutoAdjust
All again. Therefore, to ensure uninterrupted use, it is important that the ambient
room temperature remain reasonably stable.
If the sensor finds that the air temperature inside the system is too high, the system
will shut down; typically, the over-temperature shutdown point is 55°C (131°F). See
Cooling Requirements for information on air conditioning requirements.
Table 5-1 Temperature and humidity ranges for operation and storage
Operating Temperature Operating Humidity Storage Temperature
Testhead
0°C to 40°C (32°F to 104°F)
5% to 80% non-condensing -40°C to 70°C (-40°F to 158°F)
Controller 20% to 80% non-condensing -40°C to 65°C (-40°F to 149°F)
The air temperature inside the system is not considered
stable until the system has been powered for at least 30
minutes.
5-4 Site Preparation
5 Environmental Requirements
Cooling Requirements
Design the site cooling capability using the heat dissipation estimates in Table 5-2.
Humidity Requirements
The system is designed to operate in the range from 5% to 80% relative humidity
(non-condensing).
If the system is subjected to condensation, as if moved from a cold loading dock
into a warm environment, allow at least 24 hours for the system to recover before
powering up.
Table 5-2 System heat dissipation
Number of Modules Dissipation
1 module 10500 BTU (3.1 kW)
2 modules 19700 BTU (5.8 kW)
3 modules 28500 BTU (8.4 kW)
4 modules 3700 BTU (10.9 kW)