6
Service Disconnect Box. A service disconnect box is required as
per NEC.
Fuse – HACR Breakers
Protection is provided by either fuses or HACR type breakers.
Refer to the unit S&R plate and Table 7 for the maximum
overcurrent protection permitted.
Example
A CPLE120-3 is to be installed. The distance from the
building breaker box to the unit is 75’. Calculate the
minimum wire size assuming no more than 2% voltage drop.
MCA for CPLE120-3 = 43.3 (from S&R plate and table).
Applying previous table wire sizes less than #8 AWG cannot
be used for circuits which have a rating of 45A. The #8
wire is not suitable since the maximum length for a 45A
circuit is 68’. Solution, a #6 AWG wire is suitable up to
110’. Note: It is the contractors responsibility to follow the
NEC (USA) or CEC (Canada) when sizing the service wire
for this unit.
* Fuse or HACR Breaker of same value.
Line Voltage Wiring ALL line voltage wiring is to be run through
conduit from the service disconnect box to the unit. Refer to the
NEC (in Canada CEC) for the correct size conduit based on the
wire size. The conduit is to enter the control box through the hole
provided in the bottom of the control box.
Note:
hole is sized for
¾” conduit. If permitted by code, flexible conduit is preferred to
minimize vibration transmission from the unit to the building.
Connect the line voltage wires to the L1, L2, and L3 terminals of
the definite purpose contactor (located in the unit control box).
Refer to the wiring diagram attached to the unit when making
these connections.
Note:
the unit wiring diagram is also included
at the end of this manual.
¾
The wire size is appropriately sized to allow for no more than
a 2% voltage drop from the building breaker/fuse panel to the
unit.
¾
Refer to the latest edition of the National Electric Code, or in
Canada the Canadian Electric Code, when determining the
correct wire size. The following table shows the current
carrying capabilities for copper conductors rated at 75
o
C with
a 2% voltage drop.
Model
*Max. Fuse
CPLE090-3
60
CPLE090-4
30
CPLE120-3
60
CPLE120-4
35
Wire Size
(AWG)
10
15
20
25
30
35
40
45
14
75
50
37
NR
NR
NR
NR
NR
12
118
79
59
47
NR
NR
NR
NR
10
188
125
95
75
63
54
NR
NR
8
301
201
150
120
100
86
75
68
6
471
314
235
188
157
134
118
110
Max. Allowable length in Feet to Limit Voltage drop to 2%
Min. Circuit Ampacity (MCA) – CPLE Unit
Based on NEC 1996
Table 6.
Table 7.
Figure 8.
Figure 9.
As noted elsewhere in this manual, this unit must be grounded.
The electrical ground circuit must consist of an appropriately sized
electrical wire connecting to the ground lug in the unit control box
and wire to the building electrical service panel. Other methods
of grounding are permitted if performed in accordance with the
“National Electric Code” (NEC)/”American National Standards
Institute” (ANSI)/”National Fire Protection Association” (NFPA) 70
and local/state codes. In Canada, electrical grounding is to be in
accordance with the Canadian Electric Code CSA C22.1.
Low Voltage Connections The CPLE requires a 5-conductor low
voltage circuit from the room thermostat (without options). The
wires are to be no smaller than 18 AWG. The field connection for
this circuit is to be made in the unit control box using solderless
connectors such as wire nuts. See Figures 8 and 9 for a typical
low voltage hook-up.
SINGLE STAGE LOW VOLTAGE HOOK-UP
THERMOSTAT
O
W2
C
R
RED
BROWN
WHITE
BLUE
BLUE
WHITE
CONDENSING
UNIT
CPLE090/120
AIR
HANDLER
AH090/120
YELLOW
ORANGE
RED
Y
G
GREEN
TWO STAGES LOW VOLTAGE HOOK-UP
WHITE
BLUE
BLUE
WHITE
THERMOSTAT
YELLOW
ORANGE
RED
CONDENSING
UNIT
CPLE090/120
Y
O
C
W1
R
RED
BROWN
GREEN
AIR
HANDLER
AH090/120
G
W2