CSZ EZT-570i, Technical Manual

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EZT-570i Technical Manual
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4.5 Altitude System
When the altitude system is enabled, the altitude system output (Q45) will turn on. This turns on the
vacuum pump and any isolation valves to seal the chamber. The maximum dive output (Q46) and
maximum vacuum output (Q47) are controlled by the configurator settings. When the loop output
percent exceeds the configurator set point for the on delay period, the maximum output will turn on.
They operate as boost outputs, i.e., they are on/off outputs, not proportioning outputs. They connect
additional air and vacuum supply circuits to the control outputs in order to boost chamber
performance.
The altitude system automatically disables humidity, auxiliary cooling and dry air purge when it is
turned on. These systems can not run when the altitude system is on. The conditioning system is
allowed to run until the altitude reaches the conditioning system disable set point in the configurator.
Once this altitude is reached, both heating and cooling is shut down. During the allowed operating
range, the air circulator motors will switch from low speed (output Q2) to high speed (output Q44)
once the high speed fan enable set point is reached. This improves the heating and cooling
performance at higher altitudes due to the low air density in the chamber.
4.5.1 Altitude System Failures and Corrective Actions
SYMPTOM PROBABLE CAUSES CORRECTIVE ACTIONS
Chamber not increasing in altitude.
Altitude turned off.
Manual dive valve open.
Vacuum pump not running.
Leak in chamber.
9300 controller output off.
Vacuum control valve clogged/failed.
Turn on altitude event.
Close dive valve.
Check/replace fuse. Reset overload.
Check for leaks. Check door gaskets
and latches for tight seal.
Verify proper 9300 controller
configuration. Check set point.
Replace 9300 controller.
Inspect valve. Clean/Replace if
necessary.
Chamber not decreasing in altitude.
No compressed air supply.
9300 controller output off.
Air supply control valve clogged/failed.
Check/supply chamber with
compressed air. Check pressure
regulator setting.
Verify proper 9300 controller
configuration. Check set point.
Replace 9300 controller.
Inspect valve. Clean/Replace if
necessary.