Brooks Polycold MaxCool Series - Operating Modes

Polycold Cryochiller Operation
Installation and Operation Manual Single Circuit Modes of Operation
Brooks Automation
214072 Revision B
6-5
LED Status Table
Single Circuit Modes of Operation
The MaxCool Cryochiller must have a proper refrigerant line and cryosurface connected to it in order to
operate in any mode, including standby.
The Base Model cryochiller has three modes of operation.
Standby
When the unit is in Standby, the Cool and Defrost solenoid valves are closed. The unit circulates (and
cools) the refrigerant in the “stack” in the top of the refrigeration unit. The refrigerant is not pumped to
the cryosurface. The refrigerant is coldest when the unit is operating in this mode because it has the
least heat load.
All solenoids and valves are closed when in Standby mode with the exception of the following:
• Freezeout Prevention valve logic based on the FRZ_PREVENT_SETPT Host command value
controlled around the Coldest Liquid Temperature (TC4) thermocouple reading. Default is
-148C.
• Logic associated with compressor startup where the Buffer valve may be opened
• Logic for the Cylinder Unloader solenoid for power management
If the Cylinder Unloader solenoid is enabled, it is activated if the unit is in Standby for more than the time
designated by the command POWER_MGMT_STANDBY_DELAY. Default value is 20 minutes.
E_MGMT_ENABLE is enabled by default if the system is equipped with Cylinder Unloader.
Compressor will continue to run when in Standby Mode.
Table 6-2: LED Status Table
Status / LED
Cool
LED
Standby
LED
Heat
LED
OK
LED
Remote
LED
Faults
LED
Power On
Compressor Off
Off Off Off Off Off Off if
no fault
Power On
Compressor
On
As set As set As set On when
contactor on
As set Off if
no fault
At Cool On Off Off On when
contactor on
As set Off if
no fault
Standby Off On Off On when
contactor on
As set Off if
no fault
Defrost in
Process
Off Off Flash On when
contactor on
As set Off if
no fault
Defrost
Complete
Off On On On when
contactor on
As set Off if
no fault
Rapid BP
Check
Off Off Off On when
contactor on
As set Off if
no fault
Fault As set As set As set On when
contactor on
As set On