How many 250 kcmil THHN fit in 1-1/4" Flex?
1250 kcmil THHN/THWN-2 wires in 1-1/4" Flexible metal conduit (FMC, Greenfield)
1.277 sq in × 53 % = 0.6768 sq in allowed. ÷ 0.3970 sq in per wire = 1.70.
This pull in numbers
- 1 wires fill
- 31.1 % of 1-1/4" Flex
- Limit for one
- 53 %
- For 2 or more
- 2" Flex, up to 3
- Pipe to wire diameter
- 1.79 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.
250 kcmil THHN in other 1-1/4" conduit
| Conduit | Inside area | Most 250 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 |
250 kcmil THHN in other Flex sizes
Other wire sizes in 1-1/4" Flex
#14: 52#12: 38#10: 24#8: 14#6: 10#4: 6#3: 5#2: 4#1: 3#1/0: 2#2/0: 1#3/0: 1#4/0: 1250 kcmil: 1300 kcmil: 1350 kcmil: 1