Electrical Code for Wire In Conduit

Maximum Number of Wire Conductors

It is very important to understand the limitations when installing wire into conduit.

Facts About Wires in Conduit:

Wire insulation is rated upon the amount of heat it can safely withstand.

Electricity passing through wires will generate heat.

Wire fill inside conduit must never exceed the specified amount to prevent overheating of the wires inside the conduit.

Maximum Number of Conductors in
EMT - Electrical Metallic Tubing

Type

Conductor

Trade Size (in.)

THHN,
THWN,
THWN-2

Size
(AWG /
kcmil)

½

¾

1

1¼

1½

2

2½

3

3½

4

6
4
3
2
1

2
1
1
1
1

4
2
1
1
1

7
4
3
3
1

12
7
6
5
4

16
10
8
7
5

26
16
13
11
8

46
28
24
20
15

69
43
36
30
22

91
56
47
40
29

116
71
60
51
37

1/0
2/0
3/0
4/0
250

1
0
0
0
0

1
1
1
1
0

1
1
1
1
1

3
2
1
1
1

4
3
3
2
1

7
6
5
4
3

12
10
8
7
6

19
16
13
11
9

25
20
17
14
11

32
26
22
18
15

300
350
400
500
600

0
0
0
0
0

0
0
0
0
0

1
1
0
0
0

1
1
1
1
1

1
1
1
1
1

3
2
1
1
1

5
4
4
3
2

7
6
6
5
4

10
9
8
6
5

13
11
10
8
7

0
0
0
0
0

0
0
0
0
0

0
0
0
0
0

1
0
0
0
0

1
1
1
1
1

1
1
1
1
1

2
1
1
1
1

3
3
3
3
2

4
4
4
3
3

6
5
5
4
4