Control features, Control and safety feature details – WaterFurnace CLW Chiller User Manual
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CLW QUAD SERIES CHILLER INSTALLATION MANUAL
The CLW’s microprocessor based control not only monitors
and controls the heat pump but also can communicate any
of this information back to the building automation system
(BAS) clearly putting the CLW Quad Series in a class of
its own. The control will enumerate all fault and warning
conditions which can be read over a BAS as well as display
on a local user interface. An enhanced local interface is
invaluable as a service tool for the building service team
and is used to aid in diagnosing issues and the initial setup,
startup, and commissioning.
The Control Provides:
• Operational
sequencing
•
High and low-pressure safety switch monitoring
•
Monitoring motor rotation, oil temperature, and motor
windings overheating
•
Monitors for electrical thermal overloading
•
Lockouts and mode control
▶
The unit can be commanded to run from the local
display, BAS or HOA switches (manual hand-off-auto
switch) located in the low voltage panel.
▶
An alarm history can be viewed through the local
user interface.
▶
Trending of key inputs and variables are stored in the
controller and available to viewed and graphed.
▶
The Controller has unused analog and digital inputs and
outputs for field installed items such as additional water
temperature or status switches
Standard Features
•
Operational sequencing and compressor and
unit staging
•
High and low-pressure safety switch monitoring
•
Monitoring motor rotation, oil temperature, and
motor overheating
•
Monitors for electrical thermal overloading
•
Monitors for high and low saturation temperatures
•
Proves Flow prior to starting
•
Short cycle warnings
•
Lockout and mode control
DDC Operation & Connection
The controller is a native BACnet controller. Other optional
network protocols are supported via a protocol Gateway.
•
Johnson Control N2
• LonWorks
• Modbus
•
And many more
Control Features
Control and Safety Feature Details
User Shutdown
•
The shutdown mode can be activated by a command
from a facility management system or the local user
interface. When the unit is shut down any isolation
valves are close and any compressor heaters are
powered. Additionally the shutdown can be complete
and no outputs are active.
Alarm Shutdown
•
Alarm Shutdown occurs when ever an alarm condition
is present from any physical safety: refrigerant system
high pressure, refrigerant system low pressure, motor
thermal overload, motor rotation direction incorrect,
electrical thermal overload, no flow, or freeze detection.
•
Alarm Shutdown occurs when ever an alarm condition
is present from any software safety: High Sat, Low
Sat, trying to start a compressor too quickly. Other
software condition can trigger an alarm shut down
like approaching or exceeding the application range
of the compressor.
•
When any valid fault signal remains continuously
active for the length of its recognition delay, the
controller will go into fault retry mode, which will
turn off compressors. If the safety is auto resetting,
after the compressor delay time for that alarm, the
compressors will attempt to operate once again. If
four consecutive faults occur in 2 hours, the unit will
go into lockout mode.
Alarm Lockout Mode
•
Lockout mode is activated when a physical safety
requires a manual reset or a software safety with an
auto resetting safety is configured to lockout after
a number of repeated alarms in a period of time
described above.
•
The lockout condition can be reset by powering down
the controller, by a commanding the unit off from the
local display or the BAS, or by the pushing the alarm
reset button on the local display.
Refrigerant System Low Pressure
•
The low-pressure switch is a normally closed (NC)
switch that monitors the systems refrigerant pressure.
•
This safety requires a manual reset.
Refrigerant System High Pressure
•
The high-pressure switch is a normally closed (NC)
switch that monitors the systems refrigerant pressure.
•
This safety requires a manual reset.