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68
Table 66 — Power Exhaust Staging (
BP.CF
= 1)
Table 67 — Power Exhaust Staging (
BP.CF
= 2)
Smoke Control Modes
There are four 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 module (CEM). The Fire Shutdown input is
located on the main base board (MBB) on terminals TB5-10
and 11. The unit may also be equipped with a factory-installed
return air smoke detector that is wired to TB5-10 and 11 and
will shut the unit down if a smoke condition is determined.
Field-monitoring wiring can be connected to terminal TB5-8
and 9 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 connect-
ed to TB6 as shown below. Refer to Major System Compo-
nents section on page 110 for wiring diagrams.
Pressurization — TB5-12 and 13
Evacuation — TB5-12 and 14
Smoke Purge — TB5-12 and 15
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 pres-
sure 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), turning on both the power exhaust
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 will undertake when each mode occurs (outputs are
forced internally with CCN priority number 1 - “Fire”).
*“FSO” refers to the supply VFD fire speed override configurable speed.
RELEVANT ITEMS
The economizer’s commanded output can be found in
Outputs
ECON
ECN.C
.
BP.MT
= 1 (4 motors)
PE.A
PE.B
PE.C
Power Exhaust Stage 0
OFF
OFF
OFF
Power Exhaust Stage 1
OFF
ON
OFF
Power Exhaust Stage 2
ON
ON
ON
BP.MT
= 2 (6 motors)
PE.A
PE.B
PE.C
Power Exhaust Stage 0
OFF
OFF
OFF
Power Exhaust Stage 1
OFF
OFF
ON
Power Exhaust Stage 2
ON
ON
ON
BP.MT
= 1 (4 motors)
PE.A
PE.B
PE.C
Power Exhaust Stage 0
OFF
OFF
OFF
Power Exhaust Stage 1
ON
OFF
OFF
Power Exhaust Stage 2
OFF
ON
OFF
Power Exhaust Stage 3
ON
ON
OFF
Power Exhaust Stage 4
ON
ON
ON
BP.MT
= 2 (6 motors)
PE.A
PE.B
PE.C
Power Exhaust Stage 0
OFF
OFF
OFF
Power Exhaust Stage 1
ON
OFF
OFF
Power Exhaust Stage 2
OFF
ON
OFF
Power Exhaust Stage 3
ON
ON
OFF
Power Exhaust Stage 4
ON
OFF
ON
Power Exhaust Stage 5
OFF
ON
ON
Power Exhaust Stage 6
ON
ON
ON
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
SHUTDOWN
Economizer
100%
100%
0%
0%
Indoor Fan — VFD
ON/FSO*
ON/FSO*
OFF
OFF
Power Exhaust
OFF
ON/FSO*
ON/FSO*
OFF
Heat Interlock
Relay
ON
ON
OFF
OFF
Summary of Contents for WEATHERMAKER 48A2020
Page 112: ...112 Fig 20 Typical Main Control Box Wiring Schematic 48 50A Units ...
Page 113: ...113 Fig 21 Typical Auxiliary Control Box Wiring Schematic ...
Page 114: ...114 Fig 22 Typical 2 Stage Gas Heat Wiring Schematic Size 060 Units Shown ...
Page 115: ...115 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown TO NEXT PAGE ...
Page 116: ...116 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown cont ...
Page 117: ...117 Fig 24 Typical Electric Heat Control Schematic 50 Series Size 060 Units Shown ...
Page 118: ...118 Fig 25 Typical Controls Option Wiring Schematic SW1 SW2 OR DEHUMIDIFY SWITCH ...
Page 119: ...119 Fig 26 Typical Power Schematic 48 50A2 A3 A4 A5 060 Unit Shown ...
Page 120: ...120 Fig 27 Typical Power Schematic of Greenspeed Low Ambient Option 48 50A 060 Unit Shown ...
Page 121: ...121 Fig 28 Typical Small Chassis Component Location Size 020 035 Units ...
Page 122: ...122 Fig 29 Typical Large Chassis Component Locations Size 040 060 Units ...
Page 185: ...185 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716 ...