Trane IntelliPak 2 Series, Инструкция по установке, эксплуатации и обслуживанию

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22 RT-SVX24Q-EN
same effect on Exhaust Fan control as on VAV
applications with and without Statitrac.
Occupied Cooling Operation
For normal cooling operation, cooling capacity will be
staged or modulated in order to meet the calculated
discharge air target setpoint. If the current active
cooling capacity is controlling the discharge air within
the deadband, no additional cooling capacity change
will be requested. As the Discharge Air Temperature
rises above the deadband, the algorithm will request
additional capacity as required (additional compressors
or economizer). As the Discharge Air Temperature falls
below the deadband, the algorithm will request a
reduction in active capacity.
Default Economizer Operation
By default, the unit will be setup to optimize the
minimum supply fan speed capability during
Economizer Only operation. If the economizer is able to
meet the demand alone, due to desirable ambient
conditions, the supply fan speed will be allowed to
increase above the minimum prior to utilizing
mechanical cooling if discharge air setpoint falls below
the discharge air Lower Limit (Cooling) setpoint.
Unoccupied Mode
In Unoccupied mode the unit will utilize setback
setpoints, 0% Minimum OA Damper position, and Auto
Fan Mode operation as on normal CV units. The Supply
Fan speed, and cooling and modulating types of heat,
will be controlled to the discharge air target setpoint as
is done during occupied periods. The Supply fan speed
during staged heat control will be forced to 100% as on
normal CV units.
Occupied Heating Operation
Occupied heating operation has two separate control
sequences; staged and modulated. All staged heating
types will drive the supply fan to maximum flow and
stage heating to control to the Zone Heating Setpoint.
For units with Hydronic and Gas heat, modulated
SZVAV Heating. On an initial call for heating, the
supply fan will drive to the minimum heating airflow.
On an additional call for heating, the heat will control in
order to meet the calculated discharge air target
setpoint. As the load in the zone continues to request
heat operation, the supply fan will ramp-up while the
control maintains the heating discharge air
temperature. Heating can be configured for either the
energy saving SZVAV Heating solution as described
above, or the traditional, less efficient CV Heating
solution.
Compressor (DX) Cooling
Compressor control and protection schemes will
function identical to that of a traditional unit. Normal
compressor proving and disable input monitoring will
remain in effect as well as normal 3-minute minimum
on, off, and inter-stage timers. Also, all existing head
pressure control schemes will be in effect.
Cooling Sequence
If the control determines that there is a need for active
cooling capacity in order to meet the calculated
discharge air target setpoint, once supply fan proving
has been made, the unit will begin to stage
compressors accordingly. Note that the compressor
staging order will be based on unit configuration and
compressor lead/lag status.
Once the discharge air target setpoint calculation has
reached the Minimum Setpoint and compressors are
being utilized to meet the demand, as the discharge air
target setpoint value continues to calculate lower the
algorithm will begin to ramp the supply fan speed up
toward 100%. Note that the supply fan speed will
remain at the compressor stage’s associated minimum
value (as described below) until the discharge air target
setpoint value is calculated below the discharge air
temperature Minimum Setpoint (limited discharge air
target setpoint).
As the cooling load in the zone decreases the zone
cooling algorithm will reduce the speed of the fan
down to minimum per compressor stage and control
the compressors accordingly. As the compressors
begin to de-energize, the supply fan speed will fall back
to the Cooling Stage’s associated minimum fan speed,
but not below. As the load in the zone continues to
drop, cooling capacity will be reduced in order to
maintain the discharge air within the ± ½ discharge air
target deadband.
Fault Detection and Diagnostics
Fault Detection of the Outdoor Air Damper will be
evaluated based on the commanded position of the
damper compared to the feedback position of the
damper.
The damper is commanded to a position based on a 2-
10 VDC signal. If the Damper position is outside of
±10% of the commanded position, a diagnostic is
generated.
U Un niitt N No ott E Ecco on no om miizziin ng g w wh he en n iitt ssh ho ou ulld d b be e::
The Unit is operating in Cooling Mode, Economizing is
enabled and/or Mechanical Cooling is enabled. If the
Commanded Economizer Position is greater than
Current Economizer Feedback Po 10% for 5
continuous minutes, Unit Not Economizing when it
should be diagnostic is generated.
U Un niitt E Ecco on no om miizziin ng g w wh he en n iitt ssh ho ou ulld d n no ott b be e::
The unit is operating in Cooling Mode, Economizing is
enabled and or Mechanical Cooling is enabled. If the
commanded Economizer Position is less than the
current Economizer Feedback Position - 10% for 5
continuous minutes, Unit Economizing When it should
not be diagnostic is generated.
O Ou uttd do oo orr A Aiirr D Da am mp pe err N No ott M Mo od du ulla attiin ng g
G Ge en ne erra all IIn nffo orrm ma attiio on n