upgrade partial 2 wire to 3 wire

[kmehr]

If you want to do this right, stop. Going off on your own for magical solutions. This thread has already provided you with the right answer, from electricians, no less

I do want to do this right, which is why I'm continuing to ask questions and post up options. I appreciate all of the help everyone is giving, certainly a lot of knowledge here! It's also clear from the posts that there is more than one way to skin a cat, I'm just trying to look at all options and find what works best for my situation. I'm sure you can tell I don't know a whole hell of a lot about this stuff, so I apologize in advance if it comes off like I'm ignoring what people have said! Keep the advice coming!

So the XHHW-2 can be buried if in conduit correct? And then can it also be used inside the garage? (how do you tell if it is approved that?)

That https://www.wireandcableyourway.com/4-awg-xhhw-2-aluminum-building-wire.html
is a great website, thanks for the heads up.

Oh and I'm also in COVID-19 lockdown in my state, so looking for supplies that can be delivered and thus I can tackle this project while I'm stuck at home.

 

[Terry D]

Like others and i have said. Put the copper in. 6-6--6-10. Use minimum 1" conduit. I would do 1. 1/4 just in case you ever wanted to upgrade

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[pattenp]

Description of the wire insulation tells the appoved use. You can go Southwire web site and see product descriptions. Description is also on the Wire and Cable site I linked.

 

[mike93lx]

If it's not needed, it's not needed. Why waste a $100. Everyone has an opinion.

Because there is uncertainty and the difficulty and cost of redoing it all far outweighs the slightly higher up front cost, but you know all that.

Thankfully we can all do whatever we each want to.

 

[mike93lx]

I do want to do this right, which is why I'm continuing to ask questions and post up options. I appreciate all of the help everyone is giving, certainly a lot of knowledge here! It's also clear from the posts that there is more than one way to skin a cat, I'm just trying to look at all options and find what works best for my situation. I'm sure you can tell I don't know a whole hell of a lot about this stuff, so I apologize in advance if it comes off like I'm ignoring what people have said! Keep the advice coming!

So the XHHW-2 can be buried if in conduit correct? And then can it also be used inside the garage? (how do you tell if it is approved that?)

That https://www.wireandcableyourway.com/4-awg-xhhw-2-aluminum-building-wire.html
is a great website, thanks for the heads up.

Oh and I'm also in COVID-19 lockdown in my state, so looking for supplies that can be delivered and thus I can tackle this project while I'm stuck at home.

Yes, xhhw can be underground, and indoors, inside of conduit. It needs conduit everywhere because it doesn't have an outer jacket

 

[kmehr]

Ok, thanks for all the help.

Set on going with copper XHHW. Using 1.25 in conduit in case i need to upgrade in the future. #6 sounds like it will be sufficient for a welder and medium air compressor, plus some lights and other odds and ends.

Next three novice questions- 1) ground wire size- #8 looks like the minimum size for 100amps according to the NEC chart. Any reason to change that size?

2) any issue with running the conduit under or over my sprinkler lines if I need to?

3) metal or pvc conduit?

THanks, in advance

 

[Terry D]

Ok, thanks for all the help.

Set on going with copper XHHW. Using 1.25 in conduit in case i need to upgrade in the future. #6 sounds like it will be sufficient for a welder and medium air compressor, plus some lights and other odds and ends.

Next three novice questions- 1) ground wire size- #8 looks like the minimum size for 100amps according to the NEC chart. Any reason to change that size?

2) any issue with running the conduit under or over my sprinkler lines if I need to?

3) metal or pvc conduit?

THanks, in advance

XHHW is aluminum

THWN is copper

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[kmehr]

https://www.wireandcableyourway.com/xhhw/

this says it is available as copper?

 

[Terry D]

https://www.wireandcableyourway.com/xhhw/

this says it is available as copper?

Your right, it does say that. I never knew it came in copper. What is the cost difference, if any?

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[kmehr]

copper is .60 per foot vs .20 for aluminum in #6.

Even at .60/foot, im looking at around $100 for the wiring, which is totally reasonable to me.

 

[Terry D]

copper is .60 per foot vs .20 for aluminum in #6.

Even at .60/foot, im looking at around $100 for the wiring, which is totally reasonable to me.

Didn't mean to correct you, i honestly didnt know xhhw came in copper. I go to a supply house here and ask for xhhw, i get aluminum. Anyway, i dont have a code book in front of me to look it up. You said #6 aluminum, your not going to get 60 amps out of that. You would have to go to a #4

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[kmehr]

its listed as xhhw-2, so maybe the "-2" signifies copper?

I think I want to stick to copper after reading all the advice so far, and looks like everything I have now is copper. #6 copper, as per that site, has it as rated at 75 amps, which sounds like all i would need. Would you agree?

 

[wyliesdiesels]

Ok, thanks for all the help.

Set on going with copper XHHW. Using 1.25 in conduit in case i need to upgrade in the future. #6 sounds like it will be sufficient for a welder and medium air compressor, plus some lights and other odds and ends.

Next three novice questions- 1) ground wire size- #8 looks like the minimum size for 100amps according to the NEC chart. Any reason to change that size?

2) any issue with running the conduit under or over my sprinkler lines if I need to?

3) metal or pvc conduit?

THanks, in advance

That depends on definition of medium. What HP rating are you talking about?

 

[pattenp]

#6 copper is 65A at 75 deg.C. 75A is at 90deg.C which in your case you can't go by.

Also the -2 doesn't mean copper, it's part of the insulation rating. There is no good reason not to use aluminum IMO.

 

[Terry D]

its listed as xhhw-2, so maybe the "-2" signifies copper?

I think I want to stick to copper after reading all the advice so far, and looks like everything I have now is copper. #6 copper, as per that site, has it as rated at 75 amps, which sounds like all i would need. Would you agree?

That is coming from the 90 degree column. Since the terminations on you equipment is only 75 degrees, you would have to use that column which is 65 amps. The 90 degree column only really gets used for derating calculations.

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[kmehr]

@wyliesdiesels It's a 4hp craftsman with a 25 gallon tank. Currently have a Lincoln Pro-mig 140, but very likely upgrading to the Hobart 210MVP, which has a 30 amp draw max if I'm reading the specs correctly.

@pattenp are you thinking I need to step up to #4 copper?

 

[pattenp]

No, I'm not suggesting #4 copper. My suggestion in post 38 was #4 Aluminum. #4 Al is 65A but you can use a 70A breaker on it.

 

[mike93lx]

@wyliesdiesels It's a 4hp craftsman with a 25 gallon tank. Currently have a Lincoln Pro-mig 140, but very likely upgrading to the Hobart 210MVP, which has a 30 amp draw max if I'm reading the specs correctly.

@pattenp are you thinking I need to step up to #4 copper?

No one here recommends copper over aluminum for feeders. The cost difference is crazy and there is no benefit other than slightly smaller diameter. The days of dangerous copper are way behind us

 

[pattenp]

I can surely say that the Craftsman compressor you have is not a true 4HP. I dare say it has a cord and plug that uses a standard 120V 15/20A circuit.

 

[kmehr]

I can surely say that the Craftsman compressor you have is not a true 4HP. I dare say it has a cord and plug that uses a standard 120V 15/20A circuit.

Correct, but my understanding is it can be wired to 220v and then get closer to the 4hp. I also know that craftsman HP ratings are very optimistic, nonetheless that's what the sticker on the side says.

 

[mike93lx]

Correct, but my understanding is it can be wired to 220v and then get closer to the 4hp. I also know that craftsman HP ratings are very optimistic, nonetheless that's what the sticker on the side says.

Voltage doesn't change horsepower or increase power at all.

It just cuts current in half

It may be worth changing to 240v,but it will not function differently than it does now

 

[wyliesdiesels]

Correct, but my understanding is it can be wired to 220v and then get closer to the 4hp. I also know that craftsman HP ratings are very optimistic, nonetheless that's what the sticker on the side says.

Whoever told you that is wrong.

Voltage will not change HP rating.

What is the FLA rating on the nameplate?

 

[Zeke]

Getting back to your welder, the Hobart you mentioned will never continuously draw 30 amps. And if I read this forum correctly, you can wire up a 30 amp welding receptacle with 12 ga wire. I'm not saying to do that, what I'm saying is that a welder wired to the panel with 12 ga certainly is not expected to draw 30 amps continuously long enough to turn off that circuit breaker.

It has to be a dedicated circuit using a dedicated receptacle and plug although many of us are guilty of plugging up to the nearest receptacle (and 15A rated ones at that). Welders today come with too many adapters.

Your air compressor, however, will run on and on when you're using a lot of air and needs the correctly sized circuit. FLA or Full Load Amps is the draw as the compressor builds head pressure and works harder. Wylie is asking what that rating is.

I'm not qualified to tell you what many of the electricians here know better than the back of their hand. What I can tell you is that you need to report back what info there is on that compressor data plate.

That said, 10ga wire on a 30A DP 240v breaker ought to be plenty.

 

[sberry]

The welder won't turn off the breaker, it's simply a switch and for short circuit. What thermal protects the wire is applied load, about 24A for the Hobart. It's duty cycle limited and has its own internal thermal, it protects wire cord and wire ahead of it,,, will shut down before it overheats the incoming wire.
Similar to a power strip, the little breaker is not really for shorts as much as thermal.

 

[jchetty]

Ok, thanks for all the help.

Set on going with copper XHHW. Using 1.25 in conduit in case i need to upgrade in the future. #6 sounds like it will be sufficient for a welder and medium air compressor, plus some lights and other odds and ends.

Next three novice questions- 1) ground wire size- #8 looks like the minimum size for 100amps according to the NEC chart. Any reason to change that size?

2) any issue with running the conduit under or over my sprinkler lines if I need to?

3) metal or pvc conduit?

THanks, in advance

PVC conduit & run it under the sprinkler if at all possible. If you are planning to go 18” in pvc, I would think the sprinkler would be in the 6”-12” area.

 

[Zeke]

The welder won't turn off the breaker, it's simply a switch and for short circuit. What thermal protects the wire is applied load, about 24A for the Hobart. It's duty cycle limited and has its own internal thermal, it protects wire cord and wire ahead of it,,, will shut down before it overheats the incoming wire.
Similar to a power strip, the little breaker is not really for shorts as much as thermal.

Berry, I just used the wrong term. Trip is what I meant. I won't edit it since you called me on that. But the idea is there. Run that Hobart at full tilt on 14 ga w/ a 15A breaker and I bet the house breaker goes before the internal thermal one does.

 

[kmehr]

Here is what my compressor says:

4HP 25 gallon; 120/240 capable; 7 scfm at 90PSI
max psi 125; 120/240 volt 60Hz 1 phase 15.0/7.5 amps

It's a Craftsman 919.15291.

I was thinking I'd do two 220v receptacles, each with it's own breaker/circuit. THat may be overkill since I don't know when I'd really be running the welder and compressor at the same time.

 

[mike93lx]

a compressor and welder use completely different connections to plug in. you should have two circuits.

i would probably put in a disconnect and hardwire the compressor. no need to have a stationary compressor on a plug anyway and it will set you up for an upgrade down the road.

the welder will use a 50A/240V receptacle (it's 240V, not 220V, btw) and a 50A breaker.

 

[kmehr]

Ok, so now that we know what I'm working with tool wise- let me see if I've absorbed everything-

#4 aluminum wire in conduit from my main breaker box to the sub panel in the garage. I would put a 70amp breaker in my main box?

Then I would use a 70 amp sub panel, one position for the 240V welder with a 50 amp breaker, one position for the 30amp compressor breaker and circuit, then (the 70 amp sub panels i find have 4 circuits) 2 more circuits for lights and 120v outlets?

use something like this for the sub panel?:
https://www.homedepot.com/p/Square-...r-Main-Lug-Load-Center-HOM24L70RBCP/100194428

 

[mike93lx]

You can use any size panel you want as the sub. I would install at least a 20 space panel. Probably will have a 100a or 125a main in it.

Just make sure you get a main breaker panel and unbound the neutral from the case

 

[kmehr]

You can use any size panel you want as the sub. I would install at least a 20 space panel. Probably will have a 100a or 125a main in it.

Just make sure you get a main breaker panel and unbound the neutral from the case

ANd the size of the main in the sub-panle won't really matter because i can swap it out, or because the power going to it will be limited by the breaker size I install in the main box on my house that feeds it will limit it right?

 

[pattenp]

The main breaker in the subpanel is only a disconnect. Get a 100A main breaker panel. No need to swap the main breaker.

 

[mike93lx]

ANd the size of the main in the sub-panle won't really matter because i can swap it out, or because the power going to it will be limited by the breaker size I install in the main box on my house that feeds it will limit it right?

just a disconnect.

you could put in a 200A monster panel if you wanted. The wire between the buildings is protected by the breaker in the house.

 

[kmehr]

alright, wire 4-4-4-6 AL XHHW-2, conduit, 50a, 30a, 2 20a, and 60a breakers, 12 space 100 subpanel, 12/3 romex for inside, 250v outlet, 220v outlet all on order. Hopefully will get started next week.

 

[mike93lx]

alright, wire 4-4-4-6 AL XHHW-2, conduit, 50a, 30a, 2 20a, and 60a breakers, 12 space 100 subpanel, 12/3 romex for inside, 250v outlet, 220v outlet all on order. Hopefully will get started next week.

Again with the I'll informed decisions...

Why 12/3? None of the 240v circuits you have listed need a neutral.

 

[kmehr]

that was for the 120v stuff.

 

[kmehr]

and actually its 12/2, I just checked my receipt. the 12/3 was a typo.

 

[kmehr]

I bought some of this: https://www.homedepot.com/p/HydroMa...Angle-Fittings-Included-4105100050K/312429335

thinking it would be easy to use as one run from my main box, along the side of my house for about 15 feet, then underground and then to the junction box on the outside of my garage. It's listed as direct burial, outdoor, wet location and sunlight resistant. NEC 356.3 seems to allow it in a run that long as long as it is supported appropriately. Any one see any issues using it in that manner?

 

[alfredeneuman]

Nonmetallic flex is the most difficult raceway of all made to pull wire in.
Remember not to put over 360° of bends between pull points
Good Luck

 

[kmehr]

Haha dang, I thought it would be easier being all one piece...

No code issues that anyone could see?