Trane Foundation EBC180, Инструкция по установке, эксплуатации и обслуживанию

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8 RT-SVX50J-EN
Unit Description
Before shipment, each unit is leak tested, dehydrated,
charged with refrigerant and compressor oil, and run
tested for proper control operation.
Direct-drive, vertical discharge condenser fans are
provided with built-in thermal overload protection. The
stages of capacity control for these units are achieved
by starting the Economizer Control Actuator (ECA).
Economizer Control Actuator
Electromechanical Control
The ECA monitors the mixed air temperature, return air
temperature, minimum position setpoint (local or
remote), power exhaust setpoint, CO
2
setpoint, CO
2
,
and ambient dry bulb/ enthalpy sensor or comparative
humidity (return air humidity against ambient
humidity) sensors, if selected, to control dampers to an
accuracy of ±5 percent of stroke. The actuator is spring
returned to the closed position any time that power is
lost to the unit. It is capable of delivering up to 25 in
﹒ lb
of torque and is powered by 24 Vac.
JADE Economizer Control - Low Leak
Economizer (LLE) Only
The JADE controller is a standalone economizer
controller that provides outdoor air dry-bulb
economizer control standard. With optional Sylk Bus
sensors, the controller can provide comparative or
reference enthalpy control. Dampers are controlled to
an accuracy of ±3.2 percent of stroke. The actuator is
spring returned to the closed position any time that
power is lost to the actuator. It is capable of delivering
up to 88 in
﹒ lb of torque and is powered by 24 Vac.
System Input Devices and Functions
The unit must have a thermostat input in order to
operate.
For units with Low Leak Economizer (LLE), the
thermostat must be a smart thermostat as listed by the
CEC (a list of thermostats can be found at
http://www.
energy.ca.gov/title24/equipment_cert/ocst/index.html ).
The descriptions of the following basic input devices
used within the unit are to acquaint the operator with
their function as they interface with the various
features. Refer to the unit’s electrical schematic for the
specific device connections. The following controls are
available from the factory for field installation.
Drain Pan Condensate Overflow Switch
(Optional)
This input incorporates the Condensate Overflow
Switch (COF) mounted on the drain pan. When the
condensate level reaches the trip point, the COF relay
energizes and opens the 24 Vac control circuit,
disabling the unit. A delay timer prevents the unit from
starting for 3 minutes.
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 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.
Discharge Line Thermostat Control
The high pressure controls and the discharge line
thermostat signals are wired in series and connected to
the safety input of the LSD. The compressor contactor
coil is connected to the ‘CC’ terminal of the LSD. If the
high pressure control switch or the discharge line
thermostat is open, the 24 Vac signal to the SI input of
the LSD is interrupted and the compressor contactor
coil supply is disabled by the LSD. It has an automatic
lockout.
Power Exhaust Control (Optional)
The power exhaust fan is started whenever the position
of the economizer dampers meets or exceed the power
exhaust setpoint when the indoor fan is on.
The setpoint panel is located in the return air section
and is factory set at 25% (50% for LLE).
To configure the LLE controller, set EXH1 SET (or EXH1
L & EXH1 H with two-speed fan) in the SETPOINTS
menu. 2-speed fan mode requires AUX2 I set as W.
Evaporator Frost Control
This input incorporates the Frostat ™ control (FOS)
mounted in the indoor coil and can be activated by
closing a field supplied contact installed in parallel with
the FOS.
If this circuit is open before the compressor is started,
the compressor will not be allowed to operate. Anytime
this circuit is opened for 5 continuous seconds during
compressor operation, the compressor for that circuit
is immediately turned “Off”. The compressor will not
be allowed to restart for a minimum of 3 minutes
should the FOS close.
Locking Safety Device with Anti-Short Cycle
Timer
This device monitors compressor safety switch trips to
prevent short cycling, protecting the compressor. A
manual reset is required after a fourth safety switch
trip.
Sensors
High Temperature Sensor (BAYFRST003*)
This sensor connects to the Emergency Stop Input on
the LTB and provides high limit “shutdown” of the unit.
The sensor is used to detect high temperatures due to
fire in the air conditioning or ventilation ducts. The
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