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UNIT
CONNECT
VOLTAGE
AS
L1: RED +YEL
208, 230
240
L2: BLU + GRA
L1: RED
460
480
Splice BLU + YEL
L2: GRA
L1: RED
575
600
L2: GRA
Fig. 29 — Powered Convenience Outlet Wiring
Duty Cycle
The unit-powered convenience outlet has a duty cycle limita-
tion. The transformer is intended to provide power on an inter-
mittent basis for service tools, lamps, etc; it is not intended to
provide 15A loading for continuous duty loads (such as electric
heaters for overnight use). Observe a 50% limit on circuit load-
ing above 8A (i.e., limit loads exceeding 8A to 30 minutes of
operation every hour).
Maintenance
Periodically test the GFCI receptacle by pressing the TEST
button on the face of the receptacle. This should cause the in-
ternal circuit of the receptacle to trip and open the receptacle.
Check for proper grounding wires and power line phasing if
the GFCI receptacle does not trip as required. Press the RESET
button to clear the tripped condition.
Fuse on Powered Type
The factory fuse is a Bussmann Fusetron
screw-in (Edison base) type plug fuse.
USING UNIT-MOUNTED CONVENIENCE OUTLETS
Units with unit-mounted convenience outlet circuits will often
require that two disconnects be opened to de-energize all pow-
er to the unit. Treat all units as electrically energized until the
convenience outlet power is also checked and de-energization
is confirmed. Observe National Electrical Code Article 210,
Branch Circuits, for use of convenience outlets.
SMOKE DETECTORS
Smoke detectors are available as factory-installed options on
48JC models. Smoke detectors may be specified for supply air
only, for return air without or with economizer, or in combina-
tion of supply air and return air. Return air smoke detectors are
arranged for vertical return configurations only. All components
necessary for operation are factory-provided and mounted. The
1. Bussmann and Fusetron are trademarks of Cooper Technologies
Company.
PRIMARY
TRANSFORMER
CONNECTIONS
TERMINALS
H1 + H3
H2 + H4
H1
H2 + H3
H4
H1
H2
T-15, non-renewable
1
unit is factory-configured for immediate smoke detector shut-
down operation; additional wiring or modifications to unit termi-
nal board may be necessary to complete the unit and smoke de-
tector configuration to meet project requirements.
System
The smoke detector system consists of a four-wire controller and
one or two sensors. Its primary function is to shut down the roof-
top unit in order to prevent smoke from circulating throughout
the building. It is not to be used as a life saving device.
Controller
The controller (see Fig. 30) includes a controller housing, a
printed circuit board, and a clear plastic cover. The controller
can be connected to one or two compatible duct smoke sensors.
The clear plastic cover is secured to the housing with a single
captive screw for easy access to the wiring terminals. The con-
troller has three LEDs (for Power, Trouble and Alarm) and a
manual test/reset button (on the cover face).
Smoke Detector Sensor
The smoke detector sensor (see Fig. 31) includes a plastic
housing, a printed circuit board, a clear plastic cover, a sam-
pling tube inlet and an exhaust tube. The sampling tube (when
used) and exhaust tube are attached during installation. The
sampling tube varies in length depending on the size of the
rooftop unit. The clear plastic cover permits visual inspections
without having to disassemble the sensor. The cover attaches to
the sensor housing using four captive screws and forms an air-
tight chamber around the sensing electronics. Each sensor in-
cludes a harness with an RJ45 terminal for connecting to the
controller. Each sensor has four LEDs (for Power, Trouble,
Alarm and Dirty) and a manual test/reset button (on the left-
side of the housing).
DUCT SMOKE SENSOR
CONTROLLER
CONTROLLER HOUSING
AND ELECTRONICS
CONDUIT COUPLINGS
(SUPPLIED BY INSTALLER)
FASTENER (2X)
ALARM
Fig. 30 — Controller Assembly
Air is introduced to the duct smoke detector sensor's sensing
chamber through a sampling tube that extends into the HVAC
duct and is directed back into the ventilation system through a
(shorter) exhaust tube.
The difference in air pressure between the two tubes pulls the
sampled air through the sensing chamber. When a sufficient
amount of smoke is detected in the sensing chamber, the sensor
signals an alarm state and the controller automatically takes the
18
CONDUIT NUTS
(SUPPLIED BY INSTALLER)
CONDUIT SUPPORT PLATE
TERMINAL BLOCK COVER
COVER GASKET
(ORDERING OPTION)
CONTROLLER
COVER
TROUBLE
POWER
TEST/RESET
SWITCH
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