20
Circuit "A"
Circuit "B"
Model
Number
Wire Gauge
Wire Gauge
E2E(*)
and Type
Breaker Size
and Type
Breaker Size
-12-HB
#8 NM-B
40 amp
#10 NM-B
30 amp
-15-HB
#8 SEU
50 amp
#8 NM-B
40 amp
-15-HR
#6 SEU
60 amp
#10 NM-B
30 amp
-17-HB
#6 SEU
60 amp
#10 NM-B
30 amp
-20-HB
#6 SEU
60 amp
#6 SEU
60 amp
-23-HB
#6 SEU
60 amp
#6 SEU
60 amp
Copper Wire Size - See
Caution Below
60°C
90°C
( e. g . , R o mex)
( e. g . , SEU )
-010-HB
Single
45.5
60
57
4
6
10
Single
52.1
70
65
4
6
8
Dual "A"
28.0
40
35
8
8
10
Dual "B"
24.2
30
30
10
10
10
Single
66.3
90
83
2
4
8
Dual "A"
35.1
50
44
6
8
10
Dual "B"
31.3
40
39
8
8
10
Single
71.3
90
89
2
4
8
Dual "A"
48.0
60
60
4
6
10
Dual "B"
22.5
30
28
10
10
10
Single
71.3
90
89
2
4
8
Dual "A"
48.0
60
60
4
6
10
Dual "B"
22.5
30
28
10
10
10
Single
87.1
125
109
0
2
6
Dual "A"
45.5
60
57
4
6
10
Dual "B"
41.7
60
52
4
6
10
Single
93.8
125
117
0
2
6
Dual "A"
48.0
60
60
4
6
10
Dual "B"
45.5
60
56
4
6
10
-012-HB
-015-HB
-017-HB
-020-HB
-023-HB
-015-HR
2-Wire
system
maximum
wire lengths:
24 Ga.= 55'
22 Ga.= 90'
20 Ga.= 140'
18 Ga.= 225'
4 or more
Wire
systems
maximum
wire lengths:
24 Ga.= 25'
22 Ga.= 45'
20 Ga.= 70'
18 Ga= 110'
Low
Voltage
Thermostat
Wire Size
Ground
Wire
Size
Minimum
Circuit
Ampacity
Maximum
Over-current
Rating
Total
Amperes
Supply
Circuit
Model
Number
E2E(*)
* Can be H or B
CAUTION: When sizing the wire, you must follow the guidelines of the latest revision
of the NEC. NM-B wire is equivalent to “Romex” cable. SEU is equivalent to service entry
cable. For NEC type NM-B wire, you must size the wire using 60C ratings per NEC article
326.
Minimum overcurrent protection per NEC 424-3b not to be less than 125% of total amps
for fixed resistance heat.
Table 6a. Electrical Specifications
Table 6b. Recommended Electrical Application Guide for Dual Circuit Installations**
**Alternate wiring combinations can be used. Refer to the latest revision of the NEC for
these appropriate alternate combinations.
