How many 250 kcmil THHN fit in 1" ENT?
1250 kcmil THHN/THWN-2 wires in 1" Electrical nonmetallic tubing (smurf tube)
0.832 sq in × 53 % = 0.4410 sq in allowed. ÷ 0.3970 sq in per wire = 1.11.
This pull in numbers
- 1 wires fill
- 47.7 % of 1" ENT
- Limit for one
- 53 %
- For 2 or more
- 2" ENT, up to 3
- Pipe to wire diameter
- 1.45 to 1
- In THW insulation
- 0 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.
250 kcmil THHN in other 1" conduit
| Conduit | Inside area | Most 250 kcmil THHN |
|---|---|---|
| Electrical metallic tubing | 0.864 | 1 |
| Intermediate metal conduit | 0.959 | 1 |
| Rigid metal conduit (RMC, GRC) | 0.887 | 1 |
| Rigid PVC conduit, Schedule 40 | 0.832 | 1 |
| Rigid PVC conduit, Schedule 80 | 0.688 | 0 |
| Flexible metal conduit (FMC, Greenfield) | 0.817 | 1 |
| Liquidtight flexible metal conduit (LFMC) | 0.873 | 1 |
| Electrical nonmetallic tubing (smurf tube) | 0.832 | 1 |