Breaker box ain't got no holes!?

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I am installing a 120v water heater in a 208/120 breaker box. Oddly, there are no knockouts. Is that common in 208/120v?
I see three options; your advice on their legality would be appreciated.
1) I can cut a hole with a hole saw. Not a pleasant chore, but possible. 2) There is an outlet in a box just below the breaker box, connected to it by a 1/2" conduit. I could connect my MC cable to the outlet box and run the wires into the breaker box by the 1/2" conduit. I presume 1/2" conduit can take two sets of #12 cable. 3) I can run my circuit to the outlet box and attach it to the wires that feed the outlet. The outlet is only used for a radio and the water heater is only 13a, so there should be plenty of capacity.
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More than one wire can go through a single knockout.
If your wire will not fit through an existing one, relocate one of the 110v to create space.
This option is 100% legal. The others I have doubts about.
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available. It might be legal, but it isn't possible.
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I missed that part of the post. Sorry.
The other posters have good suggestions.
I would have to wonder why everything is in conduit. Is the a commercial building? Or a Condo type project?
Conduit may be a requirement for certain structures and locations.
Are they all in use? Sometimes when I have to cut open a wall to pull a wire I add some empty conduit sections to the panel box for future use. I cap both ends to prevent critter entry.
Try a rental center for the proper tool. It sounds expensive.
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It is common for industrial equipment to come without preformed KOs. Industrial electricians have KO punches and poke a hole where they need one. You can get the wrench powered ones at a good home store. Drill a 3/8" hole, assemble the cutter and die on each side and tighten it up and you cut a clean hole.
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A 7/8" hole saw cuts you a 1/2" knockout. Drill a few for the future

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RBM wrote:

nicer hole, and little or no debris inside, and no warping of the panel.
-- aem sends...
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Big difference in price between a 7/8" hole saw and a greenlee punch, besides, if he has a panel with no KO's in it, it's a commercial panel, it ain't gonna warp
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RBM wrote:

The much maligned Harbor Freight has a manual KO punch set rather cheap that would probably do the job. They also have a hydraulic driver available.
There is also the option of the Greenlee KO sized step bit, which is what I use for the small number of times I need to make holes in pull boxes and whatnot.
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Pete C. wrote: ...

If the box steel isn't harder than the punch... :)
HF -- ya pays ya money and takes ya chances...
--
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A Greenlee punch is $30 or so if you shop around and it will last a lifetime. Over the years I have managed to collect several sizes and they all still work fine.
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snipped-for-privacy@aol.com wrote: ...

Agreed...
--
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snipped-for-privacy@aol.com wrote:

Yes, but the HF set is half that. They may not last a lifetime in pro use however.
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Pete C. wrote: ...

The question w/ HF is will they last a single use??? :)
IME it's been a crapshoot...some stuff is amazingly good for the price; some is pure junk. The problem is there's almost no way to tell a priori...
Since there's no local outlet, I've pretty much given them. Doesn't mean anybody else needs to take the advice, I was simply making a (mostly) lighthearted aside...
--
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dpb wrote:

Yep, which is why having a HF retail store nearby where you can see the items in person is a huge benefit. There are a number of gems in their lineup, as well as many more perfectly serviceable for home shop use items.
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Pete C. wrote: ...

Wish I'd seen this comment before the other...is there an echo here? :)
--
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For the $15 it is sure to make one or two holes.
I retract the rental suggestion. This is the way to go.
Colbyt
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I still don't know why. To use a 1/2" KO greenlee punch, you have to drill a hole practically that large to fit the bolt through. You may as well use a 7/8" hole saw. Drill once and you're done... and it's cheaper

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How did you get the water heater IN the breaker box?
s

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jack wrote:

Why do you say that? A metal-cutting hole-saw should do the job in less than two minutes.
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