How many 300 kcmil THHN fit in 1-1/4" IMC?
1300 kcmil THHN/THWN-2 wires in 1-1/4" Intermediate metal conduit
1.647 sq in × 53 % = 0.8729 sq in allowed. ÷ 0.4608 sq in per wire = 1.89.
This pull in numbers
- 1 wires fill
- 28.0 % of 1-1/4" IMC
- Limit for one
- 53 %
- For 2 or more
- 2" IMC, up to 3
- Pipe to wire diameter
- 1.89 to 1
- In THW insulation
- 1 fit
- In XHHW-2 insulation
- 1 fit
Before you pull 1
- The ground counts. Every wire in the pipe counts toward fill, the green or bare ground and the neutrals too. 1 is the total, not the hots.
- Bends. A full pipe pulls hard. Keep to 360° of bends between pull points, less for a tight fill.
300 kcmil THHN in other 1-1/4" conduit
| Conduit | Inside area | Most 300 kcmil THHN |
|---|---|---|
| Electrical metallic tubing | 1.496 | 1 |
| Intermediate metal conduit | 1.647 | 1 |
| Rigid metal conduit (RMC, GRC) | 1.526 | 1 |
| Rigid PVC conduit, Schedule 40 | 1.453 | 1 |
| Rigid PVC conduit, Schedule 80 | 1.237 | 1 |
| Flexible metal conduit (FMC, Greenfield) | 1.277 | 1 |
| Liquidtight flexible metal conduit (LFMC) | 1.528 | 1 |
| Electrical nonmetallic tubing (smurf tube) | 1.453 | 1 |
300 kcmil THHN in other IMC sizes
Other wire sizes in 1-1/4" IMC
#14: 68#12: 49#10: 31#8: 18#6: 13#4: 8#3: 6#2: 5#1: 4#1/0: 3#2/0: 3#3/0: 1#4/0: 1250 kcmil: 1300 kcmil: 1350 kcmil: 1500 kcmil: 1