How many #12 THHN fit in 1" Liquidtight?
2612 AWG THHN/THWN-2 wires in 1" Liquidtight flexible metal conduit (LFMC)
0.873 sq in × 40 % = 0.3492 sq in allowed. ÷ 0.0133 sq in per wire = 26.26, so 26.
This pull in numbers
- 26 wires fill
- 39.6 % of 1" Liquidtight
- Limit for three or more
- 40 %
- For 27 or more
- 1-1/4" Liquidtight, up to 46
- Pipe to wire diameter
- 8.11 to 1
- In THW insulation
- 19 fit
- In XHHW-2 insulation
- 19 fit
Before you pull 26
- The ground counts. Every wire in the pipe counts toward fill, the green or bare ground and the neutrals too. 26 is the total, not the hots.
- Derating. If all 26 were current-carrying, each would be adjusted to 45 % of its ampacity (Table 310.15(C)(1)): a #12 THHN at 30 A in the 90 °C column becomes 13.5 A. Grounds don't count as current-carrying. How derating works
- Bends. A full pipe pulls hard. Keep to 360° of bends between pull points, less for a tight fill.
#12 THHN in other 1" conduit
| Conduit | Inside area | Most #12 THHN |
|---|---|---|
| Electrical metallic tubing | 0.864 | 26 |
| Intermediate metal conduit | 0.959 | 29 |
| Rigid metal conduit (RMC, GRC) | 0.887 | 26 |
| Rigid PVC conduit, Schedule 40 | 0.832 | 25 |
| Rigid PVC conduit, Schedule 80 | 0.688 | 20 |
| Flexible metal conduit (FMC, Greenfield) | 0.817 | 24 |
| Liquidtight flexible metal conduit (LFMC) | 0.873 | 26 |
| Electrical nonmetallic tubing (smurf tube) | 0.832 | 25 |
#12 THHN in other Liquidtight sizes
Other wire sizes in 1" Liquidtight
#14: 36#12: 26#10: 16#8: 9#6: 7#4: 4#3: 3#2: 3#1: 1#1/0: 1#2/0: 1#3/0: 1#4/0: 1250 kcmil: 1300 kcmil: 1