84
Smoke Control Modes
There are 4 smoke control modes that can be used to control
smoke within areas serviced by the unit: Pressurization mode,
Evacuation mode, Smoke Purge mode, and Fire Shutdown.
Evacuation, Pressurization, and Smoke Purge modes require
the controls expansion board (CEM). The Fire Shutdown input
is located on the main base board (MBB) on terminals TB201-
1 and 2. The unit may also be equipped with a factory-installed
return air smoke detector that is wired to TB201-1,2 and will
shut the unit down if a smoke condition is determined. Field-
monitoring wiring can be connected to terminal TB201-1 and 2
to monitor the smoke detector. Inputs on the CEM board can be
used to put the unit in the Pressurization, Evacuation, and
Smoke Purge modes. These switches or inputs are connected to
TB202: Pressurization — TB202-18 and 19, Evacuation —
TB202-16 and 17, and Smoke Purge — TB202-14 and 15. Re
-
fer to page 134 for wiring diagrams.
Each mode must be energized individually on discrete inputs
and the corresponding alarm is initiated when a mode is acti
-
vated. The fire system provides a normally closed dry contact
closure. Multiple smoke control inputs, sensed by the control,
will force the unit into a Fire Shutdown mode.
FIRE SMOKE INPUTS
These discrete inputs can be found on the local display under
Inputs
FIRE
.
Fire Shutdown Mode
This mode will cause an immediate and complete shutdown of
the unit.
Pressurization Mode
This mode attempts to raise the pressure of a space to prevent
smoke infiltration from an adjacent space. Opening the econo
-
mizer (thereby closing the return air damper), shutting down
power exhaust, and turning the indoor fan on will increase
pressure in the space.
Evacuation Mode
This mode attempts to lower the pressure of the space to pre
-
vent infiltrating an adjacent space with its smoke. Closing the
economizer (thereby opening the return-air damper), turning
on the power exhaust, and shutting down the indoor fan de
-
crease pressure in the space.
Smoke Purge Mode
This mode attempts to draw out smoke from the space after the
emergency condition. Opening the economizer (thereby clos
-
ing the return-air damper) and turning on both the power ex
-
haust and indoor fan will evacuate smoke and bring in fresh air.
AIRFLOW CONTROL DURING THE FIRE/SMOKE MODES
All non-smoke related control outputs will get shut down in the
fire/smoke modes. Those related to airflow will be controlled
as explained below. The following matrix specifies all actions
the control shall undertake when each mode occurs (outputs
are forced internally with CCN priority number 1 - “Fire”).
* “FSO” refers to the supply and exhaust VFD fire speed override con
-
figurable speed.
SMOKE CONTROL CONFIGURATION
The economizer’s commanded output can be found in
Out
-
puts
ECON
ECN.C
.
The configurable fire speed override for supply fan VFD is in
Configuration
SP
SP.FS
.
The supply fan relay’s commanded output can be found in
Out
-
puts
FANS
S.FAN
.
The supply fan VFD’s commanded speed can be found in
Out
-
puts
FANS
S.VFD
.
The configurable fire speed override for exhaust VFD/actuator
is in
Configuration
BP
B.V.A
BP.FS
.
The exhaust fan VFD’s commanded speed can be found in
Outputs
FANS
E.VFD
.
Indoor Air Quality Control
The indoor air quality (IAQ) function will admit fresh air into
the space whenever space air quality sensors detect high levels
of CO
2
.
When a space or return air CO
2
sensor is connected to the unit
control, the unit’s IAQ routine allows a demand-based control
for ventilation air quantity by providing a modulating outside
air damper position that is proportional to CO
2
level. The ven
-
tilation damper position is varied between a minimum ventila
-
tion level (based on internal sources of contaminants and CO
2
levels other than from the effect of people) and the maximum
design ventilation level (determined at maximum populated
status in the building). Demand controlled ventilation (DCV) is
also available when the
Comfort
Link unit is connected to a
CCN system using ComfortID™ terminal controls.
This function also provides alternative control methods for
controlling the amount of ventilation air being admitted, in
-
cluding fixed outdoor air ventilation rates (measured as cfm),
external discrete sensor switch input, and externally generated
proportional signal controls.
The IAQ function requires the installation of the factory-option
economizer system. The DCV sequences also require the con
-
nection of accessory (or field-supplied) space or return air CO
2
sensors. Fixed cfm rate control requires the factory-installed
outdoor air cfm option. External control of the ventilation posi
-
tion requires supplemental devices, including a 4 to 20 mA sig
-
nal, a 10,000 ohm potentiometer, or a discrete switch input, de
-
pending on the method selected. Outside air CO
2
levels may
also be monitored directly and high CO
2
economizer restriction
applied when an outdoor air CO
2
sensor is connected. (The
outdoor CO
2
sensor connection requires installation of the con
-
trols expansion module [CEM].)
The
Comfort
Link controls have the capability of DCV using an
IAQ sensor. The indoor air quality (IAQ) is measured using a
CO
2
sensor whose measurements are displayed in parts per
million (ppm). The IAQ sensor can be field-installed in the re
-
turn duct. There is also an accessory space IAQ sensor that can
be installed directly in the occupied space. The sensor must
provide a 4 to 20 mA output signal. The sensor connects to
TB201 terminals 7 and 8. Be sure to leave the 182-ohm resistor
in place on terminals 7 and 8.
ITEM
EXPANSION
RANGE
CCN
POINT
WRITE
STATUS
FIRE
FIRE-SMOKE INPUTS
FSD
Fire Shutdown Input
ALRM/NORM FSD
forcible
PRES
Pressurization Input
ALRM/NORM PRES forcible
EVAC
Evacuation Input
ALRM/NORM EVAC forcible
PURG
Smoke Purge Input
ALRM/NORM PURG forcible
DEVICE
PRESSURIZATION PURGE EVACUATION FIRE
SD
Economizer
100%
100%
0%
0%
Indoor Fan —
VFD
ON/FSO*
ON/FSO*
OFF
OFF
Power
Exhaust VFD
OFF
ON/FSO*
ON/FSO*
OFF
Heat Interlock
Relay
ON
ON
OFF
OFF
Содержание WeatherExpert 48N2
Страница 135: ...135 Fig 18 48 50N Typical Power Schematic Nominal 075 Ton Unit Shown ...
Страница 136: ...136 Fig 19 48 50N Typical Power Schematic Nominal Ton 90 150 Units Shown ...
Страница 137: ...137 Fig 20 48 50N Main Base Board Input Output Connections ...
Страница 138: ...138 Fig 21 48 50N RXB EXB CEM Input Output Connections a48 9307 ...
Страница 139: ...139 Fig 22 48 50N EXV SCB Input Output Connections a48 9308 ...
Страница 140: ...140 Fig 23 48N Typical Modulating Gas Heat Unit Control Wiring ...
Страница 141: ...141 Fig 24 50N Typical Electric Heat Unit Control Wiring ...
Страница 144: ...144 Fig 27 48N Typical Gas Heat Section Wiring Nominal Ton 120 to 150 Units ...
Страница 145: ...145 Fig 28 48 50N Typical Power Component Control Wiring 460 v ...
Страница 146: ...146 Fig 29 48 50N Component Control Wiring 575 v Nominal Ton 075 to 150 Units ...
Страница 147: ...147 Fig 30 48 50N Component Arrangement Power Box ...
Страница 148: ...148 Fig 31 48 50N Component Arrangement Control Box ...
Страница 168: ...168 Fig 47 Sensor and Ignition Position Fig 48 Combustion Blower Details SENSOR DETAILS IGNITION DETAILS ...
Страница 240: ...240 APPENDIX D VFD INFORMATION CONT Fig G VFD Bypass Wiring Diagram WHEN USED ...
