Product specifications

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f. Proactive control providing safeties for high pressure, low pressure and freeze protection, to
eliminate nuisance trips
g. Proactive compressor staging to eliminate overloading during start-up to reduce compressor cycling
h. Continuous evaluation of sensors
i. (Control of Hot Gas bypass)
2. Microcomputer - Unit Protection shall provide the following:
a. Low pressure cutout with Proactive safety
b. High pressure cutout with Proactive safety
c. Automatic re-start from power outage with event posting
d. Battery backed-up real time clock and memory with over 10 years life and automatic recharge of
lithium ion battery that requires no service.
e. Safeties for temporary shutdown as well as lockout protection that requires manual reset
f. Freeze protection on leaving chilled water temperature
g. Anti-recycle timing
h. Sensor error
i. Pump down - pump out failure
j. (Chilled water pump control system)
3. Microcomputer - Readouts shall provide the following:
a. Sensor inputs
b. Leaving liquid temperature
c. Entering liquid temperature
d. Compressor ampere draw
e. Suction pressure each circuit
f. Discharge pressure each refrigerant circuit
g. Unit control contacts
h. Water flow switch
i. Chilled liquid reset
j. Digital Outputs
k. Compressor control status
l. Liquid line solenoid control status
m. Condenser fan control status
n. Alarm control status
o. (Hot gas bypass status)
p. (Ambient temperature)
q. (Utility demand limit)
r. (Chilled water pump control)
s. (Electronic expansion valve)
4. Microcomputer - Setpoints shall provide the following with proper authorization):
a. High discharge pressure
b. Low suction pressure
c. Freeze protect temperature
d. Leaving liquid temperature
e. Control zone settings
f. Fan condenser control
g. Pump down - pump out settings
h. (High & low compressor amperes)
i. Low suction circuit limiting
j. High discharge circuit limiting
k. Anti-recycle delay setting
5. Microcomputer - Alarm History shall provide the following:
a. The 32 most recent alarms can be identified
b. Low suction pressure of all circuits
c. High discharge pressure of all circuits
d. Freeze protection cutout
e. Pump down - pump out failure of all circuits
f. External shutdown of each compressor
g. Communication failure
h. Battery failure
i. Time/date invalid
j. Memory failure
k. Power failure