Trane Voyager RT-SVX17C-EN, Установка, эксплуатация и обслуживание

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System Operation (Continued)
from 50 o F to 90 o F. When the zone temperature meets or
exceeds the MWU setpoint, the unit will switch to the "Cool-
ing" mode. The economizer will be held closed during the
morning warm-up cycle.
Daytime Warm-up Control
Daytime Warm-up is applicable during occupied status and
when the zone temperature is below the initiation tempera-
ture. It can be activated or deactivated through ICS or a
night setback zone sensor. If ICS or a night setback zone
sensor is not utilized, DWU can be activated by setting the
DWU enable DIP switch (RTAM) to ON and supplying a
valid morning warm-up setpoint.
The unit is shipped with a Morning Warm-up setpoint config-
ured and the Daytime Warm-up function is activated (switch
on). Opening the DWU enable switch will disable this func-
tion.
If the system control is local, the DWU initiation setpoint is 3 o
F below the Morning Warm-up setpoint. The termination set-
point is equal to the Morning Warm-up setpoint.
If the system control is remote (Tracer®), the DWU setpoint
is equal to the Tracer Occupied heating setpoint. The initia-
tion and termination setpoints are selectable setpoints desig-
nated by Tracer.
When the zone temperature meets or exceeds the termina-
tion setpoint while the unit is in an Occupied, "Auto" Mode or
switched to the "Cooling" Mode, the unit will revert to the
cooling operation.
If an Occupied "Heating" Mode is selected, the unit will only
function within the DWU perimeters until the system is
switched from the "Heat" Mode or enters an Unoccupied sta-
tus.
Supply Duct Static Pressure Control
The supply duct static pressure is measured by a transducer
with a 0.25 to 2.125 VDC proportional output which corre-
sponds to an adjustable supply duct static pressure of 0.3"
w.c. to 2.5" w.c. respectively with a deadband adjustment
range from 0.2" w.c. to 1.0" w.c.. The adjustments are made
by using the potentiometers on the RTAM or through ICS.
Example:
Supply Duct Static setpoint = 2.0" w.c. (RTAM)
Deadband = 0.2" w.c. (RTAM)
Duct Static Control Range = 1.9" w.c. to 2.1" w.c.
Transducer Voltage Output vs Pressure
Input
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
-0.
5
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5
Pressure (inches w.c.)
Volts
Variable Air Volume Applications
Supply Air Temperature Control - Occupied Cooling
The RTRM is designed to maintain a selectable supply air
temperature of 40
o
F to 90
o
F with a +/- 3.5
o
F deadband. If
supply air temperature is more than 3.5 degrees warmer
than the selected temperature, a stage of cooling will be
turned "On" (if available). Then if the supply air temperature
is more than 3.5 degrees cooler than the selected tempera-
ture, a stage of cooling will be turned "Off". At very low air-
flows (minimum of approximately 20% of design), the unit
may cycle stages "On" and "Off" to maintain an average dis-
charge air temperature outside the 7 degree deadband. The
amount of the supply air temperature swing during the cy-
cling, will be a function of: capacity of the stage, airflow at
the time, or load of the return air. These steady state control
conditions may vary during transitions or periods of large
load changes.
The RTRM utilizes a proportional and integral control
scheme with the integration occurring when the supply air
temperature is outside the deadband. As long as the supply
air temperature is within the setpoint deadband, the system
is considered to be satisfied and no staging up or down will
occur.
Supply Air Temperature Control with an Economizer
The economizer is utilized to control the supply air cooling
at
+ 1.5 o F around the supply air temperature setpoint range
of 40 o F and 90 o F providing the outside air conditions are
suitable.
While economizing, the mechanical cooling is disabled until
the economizer dampers have been fully open for three min-
utes. If the economizer is disabled due to unsuitable condi-
tions, the mechanical cooling will cycle as though the unit
had no economizer.
VHR Relay Output
During unoccupied mode, daytime warm-up (DWU) and
morning warm-up (MWU) the IGV's or VFD's will open to
100%. All VAV boxes must be opened through an ICS pro-
gram or by the VHR wired to the VAV boxes. The RTRM will
delay fan operation approximately 6.5 minutes when
switching from occupied cooling mode to a heating mode.
Zone Temperature Control without a Night Setback Panel
or ICS - Unoccupied Cooling
When a field supplied occupied/unoccupied switching device
is connected between RTRM J6-11 and RTRM J6-12, both
the economizer and the mechanical cooling will be dis-
abled.
Zone Temperature Control without a Night setback Panel
or ICS - Unoccupied Heating
When a field supplied occupied/unoccupied switching device
is connected between RTRM J6-11 and J6-12 and DWU is
enabled, the zone temperature will be controlled at 10
o F
below the Morning Warm-up setpoint, but not less than 50
o
F, by cycling one or two stages of either gas or electric heat,
whichever is applicable.
Morning Warm-up Control
Morning Warm-up is activated if the zone temperature is at
least 1.5
o
F below the MWU setpoint whenever the system
switches from Unoccupied to Occupied status. The MWU
setpoint may be set from the unit mounted potentiometer or
a remotely mounted potentiometer. The setpoint ranges are