Is it acceptable to use 3/4" steel flex conduit instead of EMT for wiring 240 receptacle plug inside my garage? This would be attached to the garage wall.
Electrical – Conduit – Flex Steel vs EMT
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Related Solutions
Electrical Metallic Tubing (Type EMT)
Pros
- Protection from physical damage
- Larger internal area (1/2" EMT = 0.622 in. ID)
- Available in sizes over 2"
- Easy to push through closed walls and bored holes.
- Can be used as equipment grounding conductor
Cons
- Requires fittings
- Costs slightly more ($0.256/ft.)
- More difficult to cut
- More difficult to bend
Electrical Nonmetallic Tubing (Type ENT)
Pros
- Easy to cut
- Easy to bend
- Long runs without fittings
- Slightly cheaper ($0.24/ft.)
Cons
- More difficult to pull through closed walls and bored holes
- Only available in sizes 1/2" to 2"
- Smaller internal area (1/2" ENT = 0.560 in. ID)
- Releases toxic fumes when burned
You want a PVC-to-threads adapter as depicted below (presumably 3/4" to match the size of the knockouts on your box, with a 1" to 3/4" PVC reducer used to adapt the LB's 1" to the adapter's 3/4").
You then use PVC from the LB to the adapter/reducer pair, and a locknut to hold the adapter to the box.
Related Topic
- Electrical – minimum height regulation for emt conduit in a garage
- Wiring – Code compliance – how to pass EMT conduit through an interior wall
- Electrical – How to relocate 50 amp hot tub wires from PVC conduit into ceiling joists
- Electrical – Adding Wires to EMT Conduit for New Circuits
- Electrical – Can PVC conduit be run through garage/house firewall
- Electrical – Garage surface conduit feed an outdoor outlet
Best Answer
The answer is fully dependent on:
For item 1, flex conduit cannot be used where subject to physical damage.
"Subject to physical damage" is subject to the inspector's opinion since the NEC does not explicitly define these terms, so I would recommend consulting with them.
Generally, wiring at a height less than 8 ft is an unwritten convention that is typically considered subject to physical damage p(rovided there are no other surround protections/enclosures/guard strips and then you're back to the inspector's interpretation).
For item 2, once you have selected the wire size appropriate to supply the required current on the circuit, you will need to calculate conduit fill to determine the allowable size of the conduit/raceway (refer to Informative Annex C of the NEC).