TestEquity 123HS, Operation And Service Manual

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Chapter 3 – Operation
Page 3-8 TestEquity 123HS Temperature/Humidity Chamber
Purge Operation
The Purge mode is enabled through Event 3 (Digital Output 3) on the F4 Controller or the Purge
button on the F4T Controller.
For low humidity control
• Turn Event 2 (
HUMIDITY)
ON and Event 3 (
PURGE)
ON.
• Purge gas will feed when the F4/F4T Controller cycles the dehumidification system. It will
cycle on/off as the workspace humidity approaches and reaches the low humidity set point,
or whenever dehumidification is necessary.
For low humidity control below +10
°
C
Turn Event 2 (
HUMIDITY)
OFF and Event 3 (
PURGE)
ON. The Purge System will continue to
provide controlled dehumidification even though the humidity system is disabled.
Adjusting the Purge Flow
A flowmeter is located on the front panel to adjust the flow of purge gas into the chamber. The
flowmeter has a scale, calibrated in SCFM. The flow of purge gas should be adjusted to the
minimum amount required to obtain the desired drying in the chamber for your particular
conditions. A suggested starting setting is 2 SCFM.
Relief Vent
Excess pressure in the chamber workspace is vented through a pressure-relief check-valve,
which is located on the top of the chamber.