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Luis Oliveira
11-15-2006, 2:11 PM
Hi all,

I want to add 220v on my garage, I contacted a licensed electrician and he said he can install one(1) 220v/30 Amp breaker. Basically out of my main panel there are only two slots left and he said 220 breaker will use both slots.
I also asked him cut it be possible to just use those two slots and feed a sub-panel. He said No.

Enough history, here is my question(s)
Some of the tools I am looking at say:
Amps
tool at 220v Single phase 10 Amps (Bandsaw)
tool at 220v Single phase 16 Amps (Bandsaw)
tool at 220v Single phase 15 Amps (Jointer)

Plug type
tool at 220v Single phase NEMA 6-15 Plug
tool at 220v Single phase NEMA 6-20 Plug
tool at 220v Single phase NEMA L6-20 Plug

So the question is if my breaker is 220v/30amps can I still have any of these plugs above.
Why would I use one plug vs another

Last question: if I decide to install 220v how do I create a longer cord, than what it is supplied with the machine? I notice the machines are usually 6' cords.

Thanks in Advance,
luis

Erik C. Hammarlund
11-15-2006, 2:53 PM
Hi all,

I want to add 220v on my garage, I contacted a licensed electrician and he said he can install one(1) 220v/30 Amp breaker. Basically out of my main panel there are only two slots left and he said 220 breaker will use both slots.
I also asked him cut it be possible to just use those two slots and feed a sub-panel. He said No.

That's odd. In my state, one can purchase "double" breakers, which use a single space in the panel and provide two circuits. They're a bit more expensive and probably have some other limitations, but they're commonly used in these situations.

So you might want to make sure this is true.

Anyway....


Enough history, here is my question(s)
Some of the tools I am looking at say:
Amps
tool at 220v Single phase 10 Amps (Bandsaw)
tool at 220v Single phase 16 Amps (Bandsaw)
tool at 220v Single phase 15 Amps (Jointer)

Plug type
tool at 220v Single phase NEMA 6-15 Plug
tool at 220v Single phase NEMA 6-20 Plug
tool at 220v Single phase NEMA L6-20 Plug

So the question is if my breaker is 220v/30amps can I still have any of these plugs above.

Yes. You can only draw a TOTAL of 30 amps at ONE TIME without tripping your breaker. But you could run all of your tools onto that single 30 amp circuit. You could then run your small 10-amp bandsaw with either of your other tools, without exceeding 30 amps. You might even be able to run the two larger tools (which technically total 31 amps); these things have been known to happen. It may be that their amp rating is startup, not run, amperage.



Why would I use one plug vs another
because that is what you happen to have on the mchine. There's really no particular advantage of any particular plug.

You should probably install wall outlets which can handle a 20 amp plug, and wire your machines to all use the same plug--that way you can move your machine easily from outlet to outlet if you need to do so.


Last question: if I decide to install 220v how do I create a longer cord, than what it is supplied with the machine? I notice the machines are usually 6' cords.
This answer is sort like giving a recipie for boiling water: You create a longer cord by removing the shorter cord and replacing it with a longer one :D

Sorry, couldn't resist. Your electricial can do this for you, I'm sure. So could you (it's not hard) but if you don't know much about power I"m loath to tell you how to do it.

JayStPeter
11-15-2006, 3:17 PM
Hi all,

I want to add 220v on my garage, I contacted a licensed electrician and he said he can install one(1) 220v/30 Amp breaker. Basically out of my main panel there are only two slots left and he said 220 breaker will use both slots.
I also asked him cut it be possible to just use those two slots and feed a sub-panel. He said No.
...
Last question: if I decide to install 220v how do I create a longer cord, than what it is supplied with the machine? I notice the machines are usually 6' cords.

Thanks in Advance,
luis

You can make your own 220V extension cords. Just get some 12 gauge flexible wire from the big wire rack at the borg (the one they cut the length you need). Then buy the plugs/sockets and screw them on the end. 12 gauge is good for up to 20 amps and will be good enough for the machines you listed. You can also use the extension cord(s) to adapt from one plug style to another based on the ends you buy for it.

John Bush
11-15-2006, 4:57 PM
Hi Luis,
Why can't a subpanel be fed off of the main panel? Is it an issue of the size of the main line coming in from the meter, or how full the main panel is? Just wondering if a 50A or 60A+ breaker to a subpanel circuit, then a couple of 30A 220V circuits for the shop. I was able to tap into my main for 125A for my shop panel 150+ feet away. I think I ran #4 wire, and all has worked well. JCB.

Kent Fitzgerald
11-15-2006, 5:36 PM
I also asked him cut it be possible to just use those two slots and feed a sub-panel. He said No.
Hmmm. Did he say why not?

I think you're going to want a subpanel in the near future. You may only be planning on running on tool at a time, but I can almost guarantee that you'll want to add another dedicated 240 V circuit for dust collection. I'd get another opinion on the subpanel issue.

Kent Fitzgerald
11-15-2006, 5:42 PM
Plug type
tool at 220v Single phase NEMA 6-15 Plug
tool at 220v Single phase NEMA 6-20 Plug
tool at 220v Single phase NEMA L6-20 Plug

So the question is if my breaker is 220v/30amps can I still have any of these plugs above.

The appropriate solution would be be a 20 A circuit with 20 A receptacles.

A 6-20 receptacle will accept a 6-15 plug.

Jim Becker
11-15-2006, 5:43 PM
I agree with Kent...you need more explaination as to why you cannot add a sub-panel. The only reason I can think of is capacity issues with the current main panel/supply.

For your tool situation, assuming only one circuit, I'd go 20 amps all around with 20 amp terminations. That will cover you for all three tools and provide common connection types. You don't need a 30 amp circuit it appears from your list of tools and ratings (20 x .8 = 16) if my understanding is correct.

Luis Oliveira
11-15-2006, 7:27 PM
Hi all, Thanks for the feedback.

Why not able to use a subpanel?

Answ: The electrician didn't go into detail, I can only assume that it is because I only have two slots available in my house panel. both slots are on the same side of the panel
-------------
- used- used-
- used- used-
- used- used-
- used- used-
- used- used-
- used- used-
- used- used-
- used- used-
------- used-
------- used-
-------------

(used) means a breaker is installed.

Q: Why not subpanel and get more outlets.
A: That is what i wanted to do, I was actually thinking of getting three outlets.

At this point I have to say one is better than none. I have a dust collector and it runs at 110v.

I guess this is the problem with new construction(3 year old house) is that everything is so calculated that at the end there is no room for expantion.

Luis

Rick Christopherson
11-15-2006, 8:33 PM
Part of me is wondering if your electrician isn't just lying to you. This is known to happen.

If your electrician can run a 240-volt circuit, then he can install a subpanel. The requirements are the same. If his reason for saying no was because you reached the ampacity limit of your main load center, the subpanel can still be limited to 30-amps and be no different than what he suggested.

Can you take some pictures of your load center with enough detail to identify breaker sizes, including the main? If not, then repeat your diagram from above, but include breaker sizes and use.

Von Bickley
11-15-2006, 8:45 PM
I agree with the other guys about the sub-panel. That 220 volt circuit doesn't know if there is a sub-panel or a receptacle on the other end.

Joe Mioux
11-15-2006, 9:31 PM
How large is your Main Panel?

200 amp

100 amp

less?

Ben Grunow
11-15-2006, 9:39 PM
220 v breakers only work with 2 slots above each other as you have in your panel (the 110 breakers only touch one bus bar inside the panel and the 220 breakers need to touch both so they need 2 slots). The twin breakers mentioned above are only available in 110 because they only need to touch one bus bar and that is possible in one slot while touching both in one slot for 220 is impossible. Make sense?

The breaker for a sub panel is the same product used for an outlet so a string of 20A outlets or a sub panel should be fine (as long as main panel capacity is not overloaded).

jeremy levine
11-16-2006, 10:25 AM
Get another electrician, I wish I could send you mine. One that will answer your questions like?

- Do I have a 100 or 200 amps service
- Why can't I get a sub

BTW new homes are generally built with lots of amp head room. 3 yr old home ? Call the builder.

Not every breaker is always needed. Some homes come with a breakers for elec. dryers but you might have gas. Same can apply to kitchen breakers.

John Bush
11-16-2006, 1:08 PM
Convince your wife that she will enjoy cooking on a wood burning stove and use that circuit for your subpanel.JCB