17
building. Observe national and local codes when selecting wire
size, fuse or breaker requirements and disconnect switch size
and location. Route 125-v power supply conductors into the
bottom of the utility box containing the duplex receptacle.
Unit-Powered Type
A unit-mounted transformer is factory-installed to step-down
the main power supply voltage to the unit to 115-v at the du
-
plex receptacle. This option also includes a manual switch with
fuse, located in a utility box and mounted on a bracket behind
the convenience outlet; access is through the unit’s control box
access panel. See Fig. 27.
The primary leads to the convenience outlet transformer are
not factory-connected. Selection of primary power source is a
customer option. If local codes permit, the transformer primary
leads can be connected at the line-side terminals on a unit-
mounted non-fused disconnect or Heating, Air Conditioning
and Refrigeration (HACR) breaker switch; this will provide
service power to the unit when the unit disconnect switch or
HACR switch is open. Other connection methods will result in
the convenience outlet circuit being de-energized when the unit
disconnect or HACR switch is open. See Fig. 29.
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
1
T-15, non-renewable
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.
ELECTRIC HEATERS
The 50JC units can be equipped electric heaters as either a fac
-
tory-installed option or a field-installed accessory. The heaters
are modular in design, with heater frames holding open coil re
-
sistance wires strung through ceramic insulators and control
contactor(s), using a combination of 24-v control side
break/auto-reset or line-break/auto-reset limit switches and a
pilot-circuit/manual reset limit switch to protect the unit
against over-temperature situations. All 50JC Model electric
heaters are one module containing either one or two banks of
electric heat coils.
Heater modules are installed in the compartment below the in
-
door (supply) fan outlet. Access is through the indoor access
panel. Heater modules slide into the compartment on tracks
along the bottom of the heater opening. See Fig. 30-32.
Fig. 30 —
Typical Access Panel Location
Not all available heater modules can be used in every unit. Use
only those heater modules that are UL listed for use in a specif
-
ic size unit. Refer to the label on the unit cabinet regarding
approved heaters.
Fig. 31 —
Typical Component Location
UNIT
VOLTAGE
CONNECT
AS
PRIMARY
CONNECTIONS
TRANSFORMER
TERMINALS
208, 230
240
L1: RED +YEL
L2: BLU + GRA
H1 + H3
H2 + H4
460
480
L1: RED
Splice BLU + YEL
L2: GRA
H1
H2 + H3
H4
575
600
L1: RED
L2: GRA
H1
H2
1. Bussmann and Fusetron are trademarks of Cooper Technologies
Company.
Control Box
Access Panel
Indoor
Access
Panel
*Optional
Factory-installed
Disconnect
Main
Control
Box
Single
Point
Box
Center
Post
Vane Axial
Indoor Fan
System
Control Wire
Terminal Block
Heater
Cover
Heater
Mounting
Bracket
Manual
Reset Limit
Switch
