CSZ EZT-570i, Technical Manual

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EZT-570i Technical Manual
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output will be of so that the wet coil solenoid can be cycled on
and off. When operating in frozen coil mode this output will turn
on in order to allow the dehumidification output of the 9300
controller to control the frozen coil solenoid instead of the wet
coil solenoid.
It also activates the bypass solenoid in order to bypass the EPR
valve on the dehumidification coil and switches control of the
purge air supply solenoid to the dehumidification output of the
9300 controller.
LN2 Supply Solenoid (Q36): This output is used to turn the LN2 supply solenoid on and off
based on chamber event 3. If the boost cool system is set for
control mode, it will automatically turn on when required in order
for the chamber to obtain temperatures below the capabilities of
the refrigeration system.
LN2 Control Solenoid (Q37): This output is used to turn the boost cooling solenoid on and off
based on the demand for cooling and settings made in the
configurator. It will turn on when the loop output exceeds the
“aux cool on percentage” for the on delay time set in the
configurator.
Rate Master Control (Q40): This output is used for rate master refrigeration systems. It is
used to switch cooling control between the system 1 and system
2 valves. When the output is turned on, system 1 is being used
to provide the cooling to the chamber. When the output is off,
system is being used to provide cooling the chamber like a
typical cascade system.
Minimum Heat/Cool Enable (Q41): This output is used to disable the cooling output from the 9300
controller, typically on chambers with defrost. When defrost is
on, this output will be off to prevent any cooling from taking place
in order to defrost the cooling coil.
On chambers that using the auxiliary cooling control, this output
is used to disable the refrigeration cooling solenoids and switch
control over to the auxiliary cooling control solenoids.
Defrost Solenoid (Q42): This output is used to turn on the hot gas defrost solenoid on
chambers equipped with defrost. This output will turn on during
the defrost period supplying hot gas to the cooling coil.
Cascade Solenoid Control (Q43):
The system 1 cascade solenoid control output is used on
chambers with rate master refrigeration systems. It is used to
disable refrigerant flow to the cascade when running in single
stage mode.