17
TRACK
FLANGE
C08135
Fig. 24 -- Typical Module Installation
Single Point Boxes and Supplementary Fuses — When
the unit MOCP device value exceeds 60--A, unit--mounted
supplementary fuses are required for each heater circuit.
These fuses are included in accessory Single Point Boxes,
with power distribution and fuse blocks. The single point
box will be installed directly under the unit control box,
just to the left of the partition separating the indoor
section (with electric heaters) from the outdoor section.
The Single Point Box has a hinged access cover. See
Fig. 25. The Single Point Box also includes a set of
power taps to complete the wiring between the Single
Point Box and the unit’s main control box terminals. Refer
to the accessory heater and Single Point Box installation
instructions for details on tap connections.
All fuses on 50TC units are 60--A. (Note that all heaters
are qualified for use with a 60--A fuse, regardless of actual
heater ampacity, so only 60--A fuses are necessary.)
Single Point Boxes without Fuses — Unit heater
applications not requiring supplemental fuses require a
special Single Point Box without any fuses. The accessory
Single Point Boxes contain a set of power taps to
complete the wiring between the Single Point Box and the
unit’s main control box terminals. Refer to accessory
heater and Single Point Box installation instructions for
details on tap connections.
A
L
L
I
E
D
P
A
M
O
D
E
L
N
O
.
ER
I
A
L
N
O.
C
O
R
P
.
11
13
21
23
O
D
2
2
.
2
3
1
2
3
ISTED
AI
R
NDITIONING
UIP
ACCESS
3
4
6
N
.
P
/
N
2-
5
6
10-
4
REV
1
1
13
2
1
2
3
CONTROL
BOX
BUSHING
SINGLE
POINT BOX
MOUNTING
SCREWS
FOAM
BUSHING
DRIP BOOT
BRACKET
MOUNTING
SCREWS
HEATER
RELAYS
POWER
WIRES
HEATER
MOUNTING
SCREWS
C08136
Fig. 25 -- Typical Single Point Installation
Low--Voltage Control Connections — Pull the
low--voltage control leads from the heater module(s) --
VIO and BRN (two of each if two modules are installed;
identify for Module #1) -- to the 4--pole terminal board
TB4 located on the heater bulkhead to the left of Heater
#1. Connect the VIO lead from Heater #1 to terminal
TB4--1. For 2 stage heating, connect the VIO lead from
Heater #2 to terminal TB4--2. For 1 stage heating with 2
heater modules connect the VIO lead from both Heater #1
and #2 to terminal TB4--1. Connect both BRN leads to
terminal TB4--3. See Fig. 26.
ORN
BRN
HR1: Heater contactor, first-stage
HR2: Heater contactor, second-stage
2
3
12
13
VIO
ORN VIO BRN
2
Plug
Assembly
Elec Htr
CTB
CONTL
BOARD
Field
Connections
VIO BRN BRNVIO
VIO BRN
VIO BRN
HR2
HR1
C09390
Fig. 26 -- Accessory Electric Heater Control
Connections
50TC
