TestEquity 123H, Operation And Service Manual

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Chapter 3 – Operation
Page 3-4 TestEquity 123H Temperature/Humidity Chamber
Loading the Chamber
!
WARNING: Do NOT put items in the chamber that could burn or explode at high
temperatures. This chamber uses open wire heating elements which generate
surface temperatures over 1000ºF. This is NOT an explosion-proof chamber.
!
WARNING: Do NOT put items in the chamber which can emit corrosive vapors or
substances.
!
WARNING: This chamber is NOT a curing oven. There are NO provisions for venting
fumes.
!
WARNING: The chamber door must remain closed while the chamber is operating. If you
need to open the door while the chamber is operating, wear safety goggles to
prevent the high velocity airflow from blowing particles or objects into your
eyes.
!
WARNING: This chamber operates at extreme temperatures. Avoid contact with air,
objects, and surfaces that are hot or cold to prevent severe burns or frostbite.
Protective gloves are recommended.
!
CAUTION: If your test sample is energized, it may be capable of raising the workspace
temperature beyond safe limits. This could occur if your test sample exceeds
the live load rating of the chamber or if the chamber’s refrigeration system
fails. This chamber has a set of contacts that can be used to remove power to
your test sample if the Limit Controller’s temperature limits are exceeded.
!
CAUTION: To prevent damage to your test sample and the chamber’s compressors, do not
exceed the live load rating of the chamber.
Live Load Capacity for Model 123H
Temp
+23°C 0°C –40°C –55°C –65°C
Watts 500 W 400 W 225 W 175 W 100 W
Performance Considerations
The performance of all chambers is significantly affected by the characteristics of your test
sample. Factors include size, weight, material, shape, and power dissipation if energized.
The test sample should be placed in the chamber in a manner that allows for air circulation. The
air plenum is located on the back wall of the chamber, where air is sucked in from the bottom
and exits from the top. You should not place the test sample directly on the chamber floor. It
should be placed on the shelf. Multiple test samples should be distributed throughout the
chamber to ensure even airflow and minimize temperature gradients. If necessary, additional
shelves should be used to evenly distribute the load. Verify that the temperature gradients are
within acceptable limits, by measuring the chamber temperature at strategic points using a
multipoint thermocouple meter or data logger.
You may find that the temperature throughout the chamber is even, but always different from
what the F4 Controller indicates. The correct way to adjust what the F4 Controller “displays”