2hp on 20 amp circuit

I think he's talking about a quad breaker. You can run four 110v, two 110v and a 220v, or two 220v circuits off a two slot quad breaker.

In the case he is discussing, it is a half, two halves tied together for a 220, and another half. The center two halves do take up a "single slot space", the catch is you need to have a half above and below it because it needs to span two poles.

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someone
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It might be worth considering if you actually find that the jointer has a problem with the 2 hp motor.

Reply to
Leon

What are you going to use it for ? If it's a question of start-up current, then so long as it doesn't have a huge cast iron head, then you should have no trouble. If you're intending to use it for typical "amateur" use with some occasional need for the extra width, then that's OK. Only if you're planning on smoothing down rough pitch pine with heavy cuts because you're in a hurry is a 2hp motor really going to need to draw that sort of current.

Personally I'd use it. But I might adjust the overload relay in the motor starter so that _that_ was what tripped first, rather than the fusebox breaker. It's not good practice to repeatedly trip fusebox breakers, they don't have the wear lifetime for it.

OTOH, I'd be lost without my 3hp cabinet saw. If this feed is the best you have to your whole workshop, then I'd certainly want to upgrade it. My own workshop has no dedicated feed at all - fortunately I'm in the UK where every outlet is 4hp as standard 8-)

Reply to
Andy Dingley

You're living on the edge as it is. When that breaker trips the lights do out. That is not a lot of fun with power tools. Since you are buying a jointer, I assume you are running other power tools also. What is the DC going to run on?

Your options may not be as limited as you think. There are was of getting power that may seem illogical, but are done all the time. Fishing a wire 90 feet may be a PITA, but it is also possible to run a line outside along the house and back into the garage. There are safe and code compliant ways of doing that. Talk to an electrician and he'll probably have a half dozen solutions to give you plenty of power for many tools. He will probably want to keep the lights and add circuits for the tools. Ed

Reply to
Edwin Pawlowski

If the breaker box is 90' away, the voltage drop will kill you.

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> Anybody know if there's any good 1.5HP 8" jointers available? Is it

It took me 2 hours and maybe $40 in materials to run a 240v line 80' to my TS. Certainly that is a better idea than replacing a motor! Don't you want to use a DC with your jointer? How are you going to do that? In fact, if you have 2 amps going to your lights, then you will be trying to put 24a on a 20a circuit just for the jointer; a horribly bad idea. I never use more than one tool at a time, but I have a 240v and 3 120v circuits to my shop; and it is not much of a shop. Somebody suggested putting in a 60a subpanel. I wish I had done that, but I put them in one at a time, thinking each would be the last one.

Reply to
Toller

In article , wrote:

DO NOT DO THIS, unless you can carefully monitor the temperature of the motor, and preferably the current going into the motor (you have to monitor the current, because you can't monitor the temperature of the motor windings, and those can get hot very quickly, before the outside of the motor becomes dangerously high). Or unless you have a supply of free replacement motors, and enjoy exchanging them.

A fixed-frequency motor is a constant power device: It will take more current if the voltage is not sufficient, to create the power that is needed by the attached equipment; it can't reduce its speed (other than stall). So under moderate load, the motor will run at 2x the current, meaning that the motor self-heating will be 4x larger than usual. Unless you are super-careful, this can very very easily burn up the windings, even if you power the motor down when it stalls.

A better idea is actually the following: The original poster said that his garage is 90 feet from the house, and the power panel is at the house, and he has only a 20A line connecting them. I suppose that the

20A line is 12-gauge, sufficient for 20A. At the house, install a 220V circuit, and connect the line to the garage to 220V. At the garage, split the wiring up into 110V outlet/lighting circuits (preferably two separate circuits), and a 220V circuit for the power tools. Install a transformer that takes the 220V coming into the garage, and splits it back up into two 110V circuits. This will not be a small or dirt-cheap transformer, and there are difficult issues with grounding, so this installation should be left to a professional. This gives you two 20A 110V circuits (for example one each for lights and for outlets), in addition to a 20A 220V circuit for larger power tools - except that the total load is limited.

There is another idea, but I'm worried about bringing it up, as it can be extremely dangerous if implemented wrong, and I fear it could never be code compliant. If the original poster is lucky, the 20A line that goes from the house to the garage has 3 wires in it: hot (black), neutral (white), and ground (bare copper), all in an outer plastic shield (like NM or UF wire). By using generous amounts of electrical tape, one could relabel those wires to be two hot wires (black and red, using the former black and white wire), and one neutral wire (using the former bare copper ground wire). Now we have one 20A 220V, or an Edison-circuit with two 20A 110V circuits with a shared neutral, going to the garage. This circuit could then be used to feed a small breaker panel in the garage, where it could be split up for example into one 220V 20A circuit, and two 110V 20A circuits. In a nutshell this is the same proposal as installing a new subpanel in the garage and feeding it with a substantial line (for example 60A), except for using a smallish line on a piece of cable that is not intended for this usage. Small problem: The garage has no ground any more. This can be cured by creating a "made ground", meaning a few ground rounds, or (if available) a ufer in the foundation. Big problem: this is completely in violation of the code; using the bare green wire for neutral is code violating, and actually dangerous: the outer jacket of the cable is not intended as an insulator, and if anyone who doesn't know about this wire ever modifies the system in the future, death becomes very likely.

Bottom line: I would just try running the tool on the 110V 20A circuit; most likely it will work most of the time. And install a battery-powered emergency light that comes on automatically if the power fails (they are about $35 at the box stores); like this if the jointer pops the breaker, the place doesn't go completely dark. And don't forget to turn the tool off before resetting the breaker - otherwise it will start up unattended when you turn power back on. A magnetic starter might be a good investment here.

Reply to
_firstname_

Actually, he is correct. While at the Home Depot, I checked it out. Only GE offers this odd setup but they really do have single unit 2 pole breakers. In order to use it however, it requires removing two standard breakers ( if the panel is full) as it sits between where the two standard ones fit. To fill in the gaps you will need to buy two half size breakers but on the positive side, by doing that you will get your 220V circuit WITHOUT losing any of your 110's and you get a spare full size breaker (in case one fails, LOL) as well.

Reply to
TBone

"Many brands of breaker panels can accommodate half-sized double pole

We built our house almost 40 years ago and used some of these duplex breakers then, they came from Sears, I think they are square D.

"the double half sized breaker would need to come in contact with both poles "

Switch a couple of 110 circuits onto a duplex breaker, use the vacated space for the 220v.

Walt Conner

Reply to
WConner

Geez... Where do you buy your electrical materials??? 6 years ago I spent $50 for 30' of cable and 2 electrical ends for 220 bolts.

Reply to
Leon

You will love the 8 inch Yorkcraft, I have one and it is wonderful once adjusted. Change over to 220 is very simple, instructions in the motor "peckerhead". In fact, my motor came wired for 220. Dave

Reply to
Dave W

That kind of depends on how they figured the hp. Yorkcraft may uses real hp and the motor may then actually draw 22A. My 5hp compressor has no problems, but then the rating says 15 OA. Have no idea what OA is but probably operating amperes, which makes 5 hp a lie anyway. It runs on a 20A circuit and has not problem running on a 15A circuit.

Reply to
George E. Cawthon

Garage sales and auctions. I have bought 250' of cable for $5, and that is not unusual.

Reply to
Toller

Cant rewire to 220V? half the amps if twice the voltage.

Doug

Reply to
Doug Schultz

Campbell Hausfeld ended up paying a huge class action suit for that. I got a free air nibbler out of the deal.

Reply to
gfretwell

My boxes have buss bars that run from one side to the other to provide both poles on both sides of the box. I looked last night, they're GE. The house is a very modest spec house built in 1990, so I'm sure the box wasn't some expensive, custom order sort of thing.

Standard breakers can (and were, in my case) be inserted into the half-space compatible slots, but only make contact with the buss bar service that side of the panel.

Trust me, they exist. My DC, cabinet saw, jointer run off half space breakers every day.

Barry

Reply to
B a r r y

No, I'm not.

It's a double-pole, SINGLE slot breaker. Similar units are available as single pole, single slot, double breakers that provide two 115v circuits in ONE slot.

Before others tell me what I really mean, I'll describe it section by section:

The breaker:

- is ONE space wide

- has TWO hot wire terminals

- has both poles tied together so either hot leg will trip both

- feeds from BOTH sides of the panel, via buss bars integral to the panel

- is branded GE

- will only work in certain slots in the panel

I also have identical versions without the poles tied together.

Barry

Reply to
B a r r y

Exactly!

I forgot about needing the 1/2 spacers, as it's been a while since I installed additional shop circuits.

Barry

Reply to
B a r r y

Then why bring it up? You're right, it is dangerous, and it does not meet Code. So what's the point in suggesting it?

Reply to
Doug Miller

I have gotten away for years with 15 to 19 amp motors on 15 amp breakers. usually the tool is ok starting up for a table saw or jointer or such. I just could ot push the tool hard. Knight-Toolworks

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handmade wooden planes

Reply to
Steve knight

To a large extent what you say is correct. However, if you lower the voltage enough, the motor could never hurt itself even if stalled since it is not a PERFECT constant power device. Second, since the breaker is limiting the current to 20 amps, which would be harder on the motor

- pulling 20 amps at 220 volts or 20 amps at 110 volts? (Acually, close to the same since most of the heating is due to winding resistance, thus equal current gives equal heating.)

In the case of the saw I mentioned, when it was wired for 220 volts, the lights hardly flickered when I started the saw and when nearly stalled, barely dimmed the lights. Now, wired for 110 volts, the room nearly goes dark when the saw is started and I never get close to stalling the motor under reasonably heavy load. This indicates to me that when wired for 220 volts and run on a 110 volt circuit, the motor CAN'T draw rated current, so can't hurt itself. After slogging through some long, heary rips, the motor wasn't more than warm to the touch when wired for 220.

However, if the OP can keep from blowing breakers, leave it at 110. If not, try the 220/110 approach and see if the power is adequate.

If it is just a matter of starting current, one could rig up a series resistance of some sort, like a 1500 watt heater, that was only in for starting and then a switch bypassed it once the motor was up to speed. A bit of a nusance, though.

Reply to
abukosky

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