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Two-Speed Indoor Fan Control
The JADE controller does not control the supply
directly but uses the following input status to
determine the speed of the supply fan and controls the
OA damper to the required position.
The W (heating mode) is not controlled by the
controller but it requires the status to know where to
position the OA damper for minimum position for the
fan speed.
The 2–speed fan delay is available when FAN SPEED is
set to 2–speed on the System Setup menu.
The 2–speed fan delay is defaulted to 5 minutes and
can be changed in the Advanced Setup menu (2SP FAN
DELAY). When the unit has a call for Y1 In and in the
free cooling mode and there is a call for Y2 In, the 2-
speed fan delay starts and the OA damper will
modulate 100% open, the supply fan should be set to
high speed by the unit controller. After the delay one of
two actions will happen:
•
The Y2 In call will be satisfied with the damper
100% open and fan on high speed and the call will
turn off.
OR
•
If the call for additional cooling in the space has not
been satisfied then the first stage of mechanical
cooling will be enabled through Y1 Out or Y2 Out.
Phase Monitor
The phase monitor is a 3 phase line monitor module
that protects against phase loss, phase reversal and
phase unbalance. It is intended to protect compressors
from reverse rotation. It has an operating input voltage
range of 190-600 Vac, and LED indicators for ON and
FAULT. There are no field adjustments and the module
will automatically reset from a fault condition.
Low Pressure Cutout
The low pressure cutouts are wired in series with the
high pressure cutouts and the temperature discharge
limits. If this circuit is open before a compressor is
started, the compressor in that circuit will not be
allowed to operate.
Anytime this circuit is opened, the compressor in that
circuit is turned off immediately.
High Pressure Cutout and Temperature
Discharge Limit
The high pressure controls and temperature discharge
limit are wired in series between the compressor
outputs on the LTB and the compressor contactors. If
the high pressure safety or temperature discharge limit
opens, the compressor on the affected circuit is turned
off.
Coil Frost Protection
The Frostat
™
control monitors the evaporator coil
temperature to prevent the evaporator from freezing
due to low operating temperatures whenever there is a
demand for cooling. When a open circuit has occurred,
the Frostat opens the 24 Vac ground and opens all of
the cooling contactors.
Initiation of Operating Modes
The JADE controller is able to initiate the following
modes: Compressor, Economizer, Fans, Heating
System, and Cooling System.
The Compressor mode is initiated by either the OAT
going above the DRYBLB SET setting or by the
thermostat initiating a call to cool when the damper is
at 100% open. The Economizer mode is controlled by
the MAT getting above the MAT SET setting while the
OAT is below the DRYBLB SET setting. While the fans
are not controlled by the controller, the Fan mode is
dependent on what state the system is in (OCC or Y1
states will cause the damper to go to a LOW fan speed
damper setting, while Y2 or W states will cause the
controller to open the damper to the HIGH fan speed
damper setting). The Heating System mode requires an
input to the AUX2-1 terminal from the thermostat, and
the Cooling System mode requires an input to the Y2
IN and/or the Y1 IN terminals from the thermostat.
Fault Detection and Diagnostics (FDD)
Certification
The JADE controller is a certified FDD product (HJW10)
by California Title 24, Part 6.
Standard Economizer Start-Up
1. Set the minimum position setpoint for the
economizer to the required percentage of minimum
ventilation using the setpoint potentiometer located
on the Economizer Control (ECA).
The economizer will drive to its minimum position
setpoint, exhaust fans (if applicable) may start at
random, and the supply fan will start when the
SERVICE TEST is initiated.
The Exhaust Fan will start anytime the economizer
damper position is equal to or greater than the
exhaust fan setpoint.
2. Verify that the dampers stroked to the minimum
position.
3. Verify that the dampers stroked to the full open
position.
4. To stop the SERVICE TEST, turn the main power
disconnect switch to the “Off” position or proceed
to the next component start-up procedure. Remove
electro mechanical test mode connections (if
applicable).
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