CVGF-SVU02B-E4
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Figure 23. Cutout strategy
Machine Protection and
Adaptive
Condenser Limit
Condenser pressure is
continuously monitored to
provide a limit function that
prevents High Pressure Cutout
(HPC) trips. This protection is
called Condenser Refrigerant
Pressure Limit, or High Pressure
Limit. A fully loaded compressor,
operating at high Evaporator
Leaving Water Temperature
(ELWT) and high condenser
temperatures causes high
condenser pressures. The
purpose of this limit is to avoid
HPC trips by allowing the chiller
to continue to run at a lower
load instead of tripping off using
HPC.
The Condenser Limit will be
based on a pressure conversion
from the Condenser Refrigerant
Temperature sensor. When
limited by this action,
“Condenser Pressure Limit” will
be displayed as a sub-operating
mode.
The Condenser Limit Setpoint is
factory set (93 percent of HPC),
however can be changed using
TechView
™
.
Chilled-Water Set Point
Differential to stop
adjustment range
X degrees minimum differential
Y degrees minimum
differential
Evaporator leaving-water
temperature cutout
Evaporator refrigerant
temperature cutout
Hold
Evaporator
limit
Integrate to trip
Evaporator limit set point
Limit loading
Unload
2°F (1.1°C)
0.5°F (0.28°C)
2.5°F (1.36°C)
Summary of Contents for CVGF 1000
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