ELECTRICAL CONNECTION TO J-BOX
Field-Supplied Electrical Box on Furnace J-Box Bracket
See Fig. 24.
1. Remove cover from furnace J-Box.
2. Attach electrical box to furnace J-Box bracket with at least
two field-supplied screws through holes in electrical box into
holes in bracket. Use blunt-nose screws that will not pierce
wire insulation.
3. Route furnace power wires through holes in electrical box and
J-Box bracket, and make field-wire connections in electrical
box. Use best practices (NEC in U.S. and CSA C22.1 in
Canada) for wire bushings, strain relief, etc.
4. Route and secure field ground wire to green ground screw on
J-Box bracket.
5. Connect line voltage leads as shown in Fig. 22.
6. Reinstall cover to J-Box. Do not pinch wires between cover
and bracket.
Electrical Box on Furnace Casing Side
See Fig. 24.
FIRE OR ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury,
death, or property damage.
If field-supplied manual disconnect switch is to be mounted
on furnace casing side, select a location where a drill or
fastener cannot damage electrical or gas components.
1. Select and remove a hole knockout in the casing where the
electrical box is to be installed.
→
Table 7—Electrical Data
FURNACE SIZE
VOLTS-
HERTZ-
PHASE
OPERATING
VOLTAGE RANGE
MAXIMUM
UNIT AMPS
UNIT
AMPACITY#
MAXIMUM
WIRE LENGTH (FT)‡
MAXIMUM
FUSE OR CKT BKR
AMPS†
MINIMUM
WIRE GAUGE
Maximum* Minimum*
045-08/024045
115-60-1
127
104
5.3
7.42
49
15
14
045-12/036045
115-60-1
127
104
7.1
9.67
38
15
14
070-08/024070
115-60-1
127
104
5.2
7.22
51
15
14
070-12/036070
115-60-1
127
104
7.3
9.90
37
15
14
070-16/048070
115-60-1
127
104
10.1
13.42
27
15
14
090-14/042090
115-60-1
127
104
8.2
10.84
34
15
14
090-16/048090
115-60-1
127
104
9.9
13.0
28
15
14
090-20/060090
115-60-1
127
104
12.9
16.70
34
20
12
110-12/036110
115-60-1
127
104
8.2
10.76
34
15
14
110-16/048110
115-60-1
127
104
10.1
13.19
28
15
14
110-22/066110
115-60-1
127
104
13.7
17.60
32
20
12
135-16/048135
115-60-1
127
104
10.2
13.28
27
15
14
135-22/066135
115-60-1
127
104
14.5
18.61
30
20
12
155-20/060155
115-60-1
127
104
15.0
19.34
29
20
12
* Permissible limits of the voltage range at which the unit operates satisfactorily.
# Unit ampacity = 125 percent of largest operating component’s full load amps plus 100 percent of all other potential operating components’ (EAC, humidifier, etc.) full
load amps.
† Time-delay type is recommended.
‡ Length shown is as measured 1 way along wire path between unit and service panel for maximum 2 percent voltage drop.
Fig. 23—Relocating J-Box
A02099
TWO
→
Fig. 24—Field-Supplied Electrical Box on
Furnace Casing
A03221
21
→
→
→
Summary of Contents for 58CTA
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