30
RT-SVX50M-EN
Note:
To disable the economizer to do functional testing,
use a 10 mm wrench to completely unsecure the
shaft coupling. After testing, tighten shaft coupling
securely onto damper shaft using minimum 120 lb-in.
(13.6 Nm) to maximum 180 lb-in. (20.3 Nm) torque.
Drain Pan Condensate Overflow Switch
(Optional)
The Condensate Overflow Switch (COF) is utilized to
prevent water overflow from the drain pan. The float switch
is installed on the corner lip of the drain pan. When the
condensate level reaches the trip point, the COF relay
energizes and opens the 24 Vac control circuit which
disables the unit. Once the 24 Vac control circuit is opened,
a delay timer will prevent unit start-up for three minutes.
Low Ambient Operation (Optional)
During low ambient operation, outside air temperature
below 50°F, the Low Ambient Controller will cycle the
outdoor fan motor "Off" and "On" based on discharge
pressure. The indoor fan motor (IDM) will continue to
operate and the outdoor fan will return to normal operation
once the ambient temperature is above 50°F.
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 three-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
180-600 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
