Trane CVGF - Manual (Page 14)

CTV-PRC001-GB 1 4
Controls
Standard Features
Field Connection
The field-connected elements are
involved in physically turning the chiller
on or off. This involves ensuring that
the chiller is not in an emergency or
external stop condition, starting the
pumps, and verifying that flow has
been established. The optional, factory-
supplied flow switch or a
customer-supplied differential-
pressure switch can be used to prove
flow.
Heat Exchanger Control
Fundamental internal variables that are
necessary to control the chiller are
gathered and acted upon by the heat
exchanger control function.
Motor Control and Compressor
Protection
This includes all functions that start,
run, and stop the motor. The starter
module provides the interface and
control of Y-delta, across-the-line,
primary reactor, autotransformer, and
solid-state starters. The motor control
also provides protection to both the
motor and the compressor.
Phase Voltage Sensors – 3 phase
Includes factory-installed potential
transformers in the starter for
monitoring and displaying phase
voltage and provides over/
undervoltage protection. DynaView,
TechView and Tracer Summit display
the following:
• Compressor phase voltage
(a-b, b-c, c-a)
• Kilowatts
• Power factor (uncorrected)
Standard Features
Chilled-Water Reset
Chilled-water reset reduces energy
consumption during periods of the
year when heating loads are high and
cooling loads are reduced. It is based
on return chilled-water temperature.
Resetting the chilled-water temperature
reduces the amount of work that the
compressor must do by increasing the
evaporator refrigerant pressure. This
increased evaporator pressure reduces
the pressure differential the
compressor must generate while in the
heat recovery mode. Chilled-water
reset is also used in combination with
the hot-water control. By resetting the
chilled-water temperature upward, the
compressor can generate a higher
condenser pressure, resulting in higher
leaving hot-water temperatures.