Johnson Controls CVWSEK-240BK/DP, Установка, эксплуатация и обслуживание

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WATERSIDE ECONOMIZER HARNESS – DUAL COMPRESSOR WIRING SCHEMATIC
SEQUENCE OF OPERATION - Dual Compressor Models
The economizer/unit control package is designed for use with a conventional 24-Volt cooling thermostat. A
JOHNSON CONTROL
System 450 Control Module C450CCN-3C
– with remote sensor – is used to measure the
temperature of the cooling water supplied to the unit. The C450CCN-3C will energize/de-energize its relay output
stages as dictated by the deviation of the measured water supply temperature to the control set point. The LEDs
in
C450CCN-3C indicate its relay status. When water temperatures are suitable for economizing, the control
circuit will engage a JOHNSON CONTROLS M9106 actuator motor; driving a 3-way diverting valve. The actuator
motor power supply is 24vac, connected to the motor for 2-postion control logic.
The control set point for the economizing cycle is user-adjustable. The recommended operating set point is 55
o
F.
Entering Water Temperatures higher than this value (i.e. 60
o
F) will provide only marginal cooling benefit from the
economizing coil
– near continuous operation of the compressor circuits may be required to maintain desired
space temperature.
Economizer Operation Scenarios
Scenario A
Entering water temperature is above 55
o
F and not adequate for economizer cooling.
Scenario B
At the factory economizer activation set point of 55
o
F or less, the economizer coil will be activated, and
compressor operation will be maintained. Total unit capacity is significantly increased, thereby reducing
compressor operating time. Water valve will be activated to allow water flow through coil and condensers.