triplex to a detached garage (3 wire ?)

[Stevenfyeager]

just for one 120 v circuit to a detached garage, is 3 wire triplex ok ? I have had to run a 4 wire triplex to a detached garage on other jobs but that was for a garage sub panel, drove a grd rod, too. But for just one circuit, 3 wire is ok ? no rod ? Thank you

 

[Dennis Alwon]

You are correct

 

[augie47]

One possible problem, IMO, if it is actually a garage then 210.52(G_) requires a receptacle and 210.11(C)(4) requires that circuit have no other outlets but 210,70 requires a lighting outlet.
Seemingly you can't supply a garage with one circuit unless its a MWBC

 

[Dennis Alwon]

Good catch-- didn't think that far.

 

[kwired]

One possible problem, IMO, if it is actually a garage then 210.52(G_) requires a receptacle and 210.11(C)(4) requires that circuit have no other outlets but 210,70 requires a lighting outlet.
Seemingly you can't supply a garage with one circuit unless its a MWBC

True but still can have a 120 volt feeder and multiple branch circuits in the garage though, which would still allow use of "triplex" for the feeder.

 

[480sparky]

One possible problem, IMO, if it is actually a garage then 210.52(G_) requires a receptacle and 210.11(C)(4) requires that circuit have no other outlets but 210,70 requires a lighting outlet.
Seemingly you can't supply a garage with one circuit unless its a MWBC

120v, 30 or 40 amps to garage. Split into two 120v 15- and/or 20-amp circuits.

 

[don_resqcapt19]

True but still can have a 120 volt feeder and multiple branch circuits in the garage though, which would still allow use of "triplex" for the feeder.

But making it a feeder, triggers the requirement to have a grounding electrode system at the garage. Not needed when the supply to the garage is a branch circuit.

 

[Stevenfyeager]

But making it a feeder, triggers the requirement to have a grounding electrode system at the garage. Not needed when the supply to the garage is a branch circuit.

And a feeder would also require 4 wires, correct ?

 

[LarryFine]

And a feeder would also require 4 wires, correct ?

Only if you want 120/240v.

 

[Stevenfyeager]

I see that, thanks. Like 480sparky suggested, I could just feed 30 amps, 120 v and still get a lighting circuit and a receptacle circuit.

 

[augie47]

correct, but in regard to your 1st post, keep in mind with a feeder you will need to establish a grounding electrode system.

 

[goldstar]

correct, but in regard to your 1st post, keep in mind with a feeder you will need to establish a grounding electrode system.

I thought that was true only if you run an MWBC type feeder. Please correct me if I'm wrong.

 

[augie47]

The way I read it, 250.32 requires a grounding electrode system at all detached structures with power with an exception for single branch circuits (including MWBC)
Once you run a feeder of any type, an electrode is needed,

 

[GoldDigger]

And if you put OCPD in the garage, whether or not you separate into more than one circuit, it still makes the wire to the garage a feeder.

 

[Srv52761]

A detached garage, shed, etc., that is supplied with power from a single circuit requires that circuit to be gfci protected upstream of its burial, correct?
How does gfci work on a mwbc?

 

[goldstar]

The way I read it, 250.32 requires a grounding electrode system at all detached structures with power with an exception for single branch circuits (including MWBC)
Once you run a feeder of any type, an electrode is needed,

- And if you put OCPD in the garage, whether or not you separate into more than one circuit, it still makes the wire to the garage a feeder.

OK - thanks for the clarification Now I see the difference. You can run a single branch circuit or an MWBC to a detached garage and no additional ground rod is needed (please correct me if I'm wrong). Once you install over-current devices in the garage then those circuits are considered feeders and a ground is required.

In the case of just branch circuits run to a detached garage (as I understand it), a disconnect means must be provided inside the garage ahead of light switches or receptacles. I don't mean to pirate this thread from the Op but in the case of running a feeder are the over-current devices considered the disconnect means or is an additional disconnect required ahead of the over-current protection ?

 

[kwired]

A detached garage, shed, etc., that is supplied with power from a single circuit requires that circuit to be gfci protected upstream of its burial, correct?
How does gfci work on a mwbc?

210.8 only requires GFCI protection of the receptacle outlets, which can be done at the receptacle(s) themselves. Lighting outlets don't require GFCI protection.

One might protect it at the supply end in order to take advantage of certain conditions in 300.5 that would allow less burial depth if GFCI protected.

Otherwise to GFCI protect a MWBC you would need a 2 pole GFCI breaker.

 

[augie47]

OK - thanks for the clarification Now I see the difference. You can run a single branch circuit or an MWBC to a detached garage and no additional ground rod is needed (please correct me if I'm wrong). Once you install over-current devices in the garage then those circuits are considered feeders and a ground is required.

In the case of just branch circuits run to a detached garage (as I understand it), a disconnect means must be provided inside the garage ahead of light switches or receptacles. I don't mean to pirate this thread from the Op but in the case of running a feeder are the over-current devices considered the disconnect means or is an additional disconnect required ahead of the over-current protection ?

Take a look at 225.32. It describes the type of disconnects acceptable, location, etc.

 

[Srv52761]

So, if it is a “defined garage” you need two circuits minimum.
But you may only run one circuit (or mwbc) without running a feeder/sub panel.
Hence, if you don’t want to install a sub panel, a mwbc is your only option. Is that correct?

 

[augie47]

as I see it, yes