Duty Cycle; Maintenance; Fuse On Powered Type; Smoke Detectors - Carrier 48FC 08-16 Series Service And Maintenance Instructions

Single package rooftop gas heat/electric cooling unit with puron (r-410a) refrigerant 7.5 to 15 nominal tons
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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. 38 — Powered Convenience Outlet Wiring

Duty Cycle

The unit-powered convenience outlet has a duty cycle limitation.
The transformer is intended to provide power on an intermittent ba-
sis for service tools, lamps, etc; it is not intended to provide 15A
loading for continuous duty loads (such as electric heaters for over-
night use). Observe a 50% limit on circuit loading 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 internal 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 re-
quire that two disconnects be opened to de-energize all power to
the unit. Treat all units as electrically energized until the conve-
nience outlet power is also checked and de-energization is con-
firmed. Observe National Electrical Code Article 210, Branch Cir-
cuits, for use of convenience outlets.
1. Third-party trademarks and logos are the property of their respective
owners.
PRIMARY
TRANSFORMER
CONNECTIONS
TERMINALS
H1+H3
H2+H4
H1
H2+H3
H4
H1
H2
1
T-15, non-renewable

SMOKE DETECTORS

Smoke detectors are available as factory-installed options on
48FC models. Smoke detectors may be specified for supply air
only, for return air without or with economizer, or in combination
of supply air and return air. Return air smoke detectors are ar-
ranged for vertical return configurations only. All components
necessary for operation are factory-provided and mounted. The
unit is factory-configured for immediate smoke detector shutdown
operation; additional wiring or modifications to unit terminal
board may be necessary to complete the unit and smoke detector
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. 39) includes a controller housing, a print-
ed 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 controller has three
LEDs (for Power, Trouble and Alarm) and a manual test/reset but-
ton (on the cover face).

Smoke Detector Sensor

The smoke detector sensor (see Fig. 40) includes a plastic housing,
a printed circuit board, a clear plastic cover, a sampling 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 airtight chamber around the sensing
electronics. Each sensor includes 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 (x2)
Alarm
Fig. 39 — Controller Assembly
30
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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