Specifications

13
o Defrost Mode
 If this alarm and defrost term temp sensor alarm, reverse cycel defrost will last only three
minutes with valve open;
 If this alarm and defrost term temp sensor alarm, electric defrost will last only ten minutes
with valve closed.
• Room temp sensor alarm (ATSA)
o Cool Mode
 Run on superheat control for the minimum compressor run time
 Close valve for the minimum compressor off time
 Keep doing above cycle until alarm goes away.
• Low superheat alarm (LOSH)
o Close valve and wait for alarm to go away.
• High Room Temperature Alarm (HITA)
The ‘high room temperature alarm’ occurs when the room temperature is above the preprogrammed ‘HIGH
TEMPERATURE ALARM’ for a preprogrammed number of minutes. The alarm is cleared when the room
temperature is less than the ‘HIGH TEMPERATURE ALARM’ set point.
• Low Room Temperature Alarm (LOTA)
The ‘low room temperature alarm’ occurs when the room temperature is below the preprogrammed ‘LOW
TEMPERATURE ALARM’ for a preprogrammed number of minutes. The alarm is cleared when the room
temperature is above the ‘LOW TEMPERATURE ALARM’ set point.
• Defrost term temp sensor alarm (CTSA)
o Defrost mode
 Open valve until alarm goes away or defrost terminates.
 If this alarm and outlet temp sensor alarm, defrost will last only three minutes.
 Use outlet sensor for defrost temperature termination
• Communication alarm (COMA)
o For Alternating mode, (ALTN) go to standalone mode.
o For Synchronous mode, (SYNC)
 Cool mode
• Run on superheat control for the minimum compressor run time
• Close valve for the minimum compressor off time
• Keep doing above cycle until alarm goes away.
 Pumpdown Mode
• Wait until pump down time times out.
 Drip Mode
• Wait until Drip time times out.
 Defrost Mode
• Valve will close when defrost termination temperature meets its set point if reverse
cycle defrost. Valve will close at all time if electric defrost. It will then wait the full
defrost time for other evaporators to defrost..
• If in demand defrost mode, defaults to three defrosts per day.
Multiple Evaporator Configuration
The Master Controller 2.0 can be configured with 1 to 8 other controllers. Each controller is appointed a static I/P
address at the factory for communication and sequence of operation. The evaporators are piped together to one
condensing unit. The room temperature sensor is mounted on any of the controllers. All controllers can have a room
temperature sensor connected for better control. All evaporators have a pressure transducer, outlet sensor and coil
sensor. All controllers will communicate with each other to share the room temperature reading and the coil
temperature reading. All controllers can modulate its electric expansion valve independently.
• The communication cable is a CAT/5E cable, up to 330 feet.
• Communication for peer to peer control are connected to the RJ-45 connector.