110 vs 220

[Julie Moriarty]

I vote to bite the bullet and install 220v. Running heavy equipment on 110v limits your ability to run things simultaneously like a DC, a sander, shopvac or even a grinder.

If you install 220, have them drop a couple outlets around your shop. The additional drops will hardly add to the cost, and you'll then have many options for relocation if you wish.

In theory and in most practice 110v machines and 220v machines consume the same power. However, if the run to your source is quite long, it can be more efficient and less lossy to run that higher power at a higher voltage than a higher current. When I used to run my 6" jointer on 110v, the lights on the same circuit would dim for a second or two. I'm not sure if that sag was detrimental to the motor of the jointer motor.

The only time running things simultaneously would be a problem is if they are on the same circuit and the total load exceeds the breaker capacity. If you have a large machine, one that draws close to the ampacity of the breaker, you should have other outlets in your shop that are on a different circuit. I have my DC on a dedicated circuit because it's always running when one of the larger machines are running.

The whole concept behind using a single pole, 120V circuit vs. a two-pole 240V circuit is the two-pole circuit allows you to use smaller wire because the load is split across the poles. Distance from the panel usually only becomes an issue when that distance becomes quite long. Then the resistance in the additional length increases the overall load. Many jobs I was on we'd automatically up the wire size when the distance got to around 150'.

The dimming of lights you are experiencing is caused by the start up load of the jointer. It requires more power to take a motor from a dead stop to full capacity than it does to keep that motor running. But if the dimming is substantial, you may have a wiring issue or just had too much of a load already on the circuit when you started your jointer.

[Prashun Patel]

When I switched to 220 the dimming stopped. I was indeed sharing that circuit with the lights so shame on me. The circuit was 20a and had 12 gauge wire. The run was about 120 feet.

[Julie Moriarty]

When I switched to 220 the dimming stopped. I was indeed sharing that circuit with the lights so shame on me. The circuit was 20a and had 12 gauge wire. The run was about 120 feet.

Manufacturers and retailers aren't going to make a big issue about the fact that machine they are selling, touting the awesome power it has, may require a dedicated circuit. Your experiences aren't unusual.

Dimming lights are not always created by a power surge, as it was in your case. Sometimes how the building is wired is the problem. In the typical residential panel you have two 120V legs, a neutral and a ground. As long as it's on the same leg, hots can be crossed without tripping a breaker. Ground and neutral can be crossed without immediately obvious problems. But this wreaks havoc on the overall electrical system and people begin to wonder if a poltergeist has emerged. DIYers have provided a lot of interesting scenarios for me that I never saw on the jobsites, and I get to see just how strangely electricity behaves if the installer doesn't know what they are doing. For me, it's a fun challenge. For the building owner who tried to save a buck, it's expensive.

[Phillip Gregory]

The reason for running an induction motor of greater than 1.5 hp on a 240 V circuit is that the current draw will likely exceed the capacity of a typical 120V circuit (20A). In fact, you aren't likely to even find a 120V motor with greater than a 1.5 HP rating.

*Not counting universal motors or Craftsman induction motors, the horsepower ratings for which are pure fiction.

There are some pieces of equipment with actual 2 hp induction motors that can be wired 120 V or 240 V. Delta used to make some of their contractor saws that way and Grizzly sells at least a few tools with dual-voltage 2 hp motors. I have a Grizzly G0513 bandsaw that has such a 2 hp motor. The issue is that the full load amp draw of a 2 hp motor on 120 V will be right at 20 amps and may be difficult to run even on a short-run 20 amp 120 V circuit. A 1.5 hp motor draws just under 15 amps at 120 V and is much easier to run on a 20 amp 120 V circuit.

One thing to note however is that my bandsaw's motor was wired for 240 V operation out of the box, had a 14 gauge pigtail cord for 240 V operation (instead of a 10 ga cord for 120 V operation) and the manufacturer strongly recommends running it on 240 V. They also require the saw be on a 30 amp 120 V circuit if you wanted to run it on 120 V. Essentially, it's a case of "you can run it on 120 V, but it's really a 240 volt motor."

Jeff, there are no operating savings for using 220 vac. The amount of power consumed by the 1 HP motor will remain the same. The major value for using 220vac is you can use a smaller diameter wire as it will use 1/2 the current of it's 110 vac equivalent cousin. The wattage or power consumed will remain the same.

There will actually be no savings in running a 1 hp motor on 240 V vs. 120 V. The amperage draw will be <15 amps on 120 V and the smallest branch circuit you can run for either 120 V or 240 V is 15 amps. The only reason I would run a 1 hp motor on 240 V is if there is more "congestion" on the 120 V circuits than on the 240 V circuits, such as if you share the circuit for the lathe with the DC or your lights. Now on any larger of a motor, you'd do better with 240 V than 120 V because the amp draw would be around or over 15 amps on 120 V.

However, if I were you, I would certainly add a 240 V branch circuit than a 120 V branch if you are going to add any branches. Having a 20 amp 240 V branch lets you run up to 3 hp equipment.

[allan kuntz]

Jeff, there are no operating savings for using 220 vac. The amount of power consumed by the 1 HP motor will remain the same. The major value for using 220vac is you can use a smaller diameter wire as it will use 1/2 the current of it's 110 vac equivalent cousin. The wattage or power consumed will remain the same.

Ken here in Canada you can run 110 or 220 on the same size wire but it is the amps that make the difference. If it is 15 amp you use 14 gauge wire and if it is 20 amp you use 12 gauge. It does not matter if it is 110 or 220
Al

[Mike Henderson]

Ken here in Canada you can run 110 or 220 on the same size wire but it is the amps that make the difference. If it is 15 amp you use 14 gauge wire and if it is 20 amp you use 12 gauge. It does not matter if it is 110 or 220
Al

It's the same in the US - the wire is sized to the amp carrying capacity, not the voltage. Electricity is universal.

Mike

[Allan Speers]

Actually, there are some small but concrete differences between 120 & 240, when you have a motor that gives you a choice.

With a 120v wired motor at the edges of your circuit's capacity, you can get losses in the run from the wall outlet to the tool, due to heat. It can also affect your spool-up speed, and cause dragging of the motor on start up.

[Wade Lippman]

I don't know anything about the Oneway, but the Jet1642 trips a GFCI outlet. In some places (such as unfinished basement or garage) 120v has to be GFCI and 240v doesn't; so 240v would be the only legal option.

Doncha love electrical threads? Everyone has an opinion, and about half are confused.

[Mike Henderson]

Actually, there are some small but concrete differences between 120 & 240, when you have a motor that gives you a choice.

With a 120v wired motor at the edges of your circuit's capacity, you can get losses in the run from the wall outlet to the tool, due to heat. It can also affect your spool-up speed, and cause dragging of the motor on start up.

I think everyone has said the same thing: A motor running at 120V will require twice the amps as the same motor running at 240V. If your wiring is insufficient, there will be sufficient losses in the wire, due to the resistance of the wire, (which losses will be dissipated as heat) that the motor will not perform well. This is true at both 120V and 240V.

If your wiring is sufficient, the motor will perform exactly the same, have the same startup, have the same power, dissipate the same heat, etc. on 120V as on 240V. The reason most people believe that 240V works better is that the wiring for 120V, which has to carry twice the current, is often insufficient.

Mike

[Julie Moriarty]

In some places (such as unfinished basement or garage) 120v has to be GFCI and 240v doesn't; so 240v would be the only legal option.

There is an exemption for dedicated circuits and receptacles. The rules regarding GFCI circuits normally apply to convenience outlets. I would think most inspectors would permit non-GFCI protected receptacles to be installed, where they would normally be required, if you explained to them those receptacles will be dedicated to machinery. In the conversations I've had with inspectors, I'd say most want to make sure you are safe, and that usually includes the fact you have a good understanding what you are doing.

If you make part or all of a garage or an unfinished basement into a workshop, you are changing the intended use of the space. If the inspector has worked as an electrician (not all have) he or she would know certain equipment cannot run on GFCI protected circuitry and would most likely allow for non-GFCI receptacles to be installed. But when you sell your home, you may be required to return the electrical changes you've made back to their original state.

[Curt Harms]

Actually, there are some small but concrete differences between 120 & 240, when you have a motor that gives you a choice.

With a 120v wired motor at the edges of your circuit's capacity, you can get losses in the run from the wall outlet to the tool, due to heat. It can also affect your spool-up speed, and cause dragging of the motor on start up.

Usually seen when the same 20 amp circuit is powering the lights .... and the fan ..... and an appliance in the kitchen .... and the table saw .... through a 16 or 18 ga. extension cord ... and you get the idea.

[Gary Salisbury]

Ken here in Canada you can run 110 or 220 on the same size wire but it is the amps that make the difference. If it is 15 amp you use 14 gauge wire and if it is 20 amp you use 12 gauge. It does not matter if it is 110 or 220
Al

That is interesting since the resistance of the tool remains the same, the amperage drops in half when the voltage goes from 120VAC to 240VAC therefore the wires size could be smaller with 240VAC. For example, a 1½ HP motor draws 20 amps at 120VAC and 10 amps at 240VAC.

One thing to remember when making a decision whether to run your multi-voltage tools on 120VAC or 240VAC is that the 240VAC circuit takes two circuit breakers as opposed to the one a 120VAC circuit uses. Breaker space in your panel may dictate what you can do.

[Mike Chalmers]

That is interesting since the resistance of the tool remains the same, the amperage drops in half when the voltage goes from 120VAC to 240VAC therefore the wires size could be smaller with 240VAC.

All Ken is saying is that the wire size is dictated by the amperage, not the voltage. You are correct that 20 amps on 110v is 10 amps per leg on 220v, therefore per wire, however, that is not really relevant to Ken's comment. At least that is how I read it, and it is a correct statement.

[Mike Henderson]

All Ken is saying is that the wire size is dictated by the amperage, not the voltage. You are correct that 20 amps on 110v is 10 amps per leg on 220v, therefore per wire, however, that is not really relevant to Ken's comment. At least that is how I read it, and it is a correct statement.

A circuit is made up of two wires for single phase power. The amperage through the circuit is dependent upon the load.

There is no concept of "per leg" in either 120V or 240V. There is just two wires, both of which carry the full current of the load.

I think perhaps that people get confused by the term "hot" leg - there being one wire that has 120V to ground in a 120V circuit with the other wire essentially at ground. But that "neutral" wire carries the same current as the "hot" wire. The fact that it is at close to ground potential has no relevance to the current that it carries.

In a 240V circuit, both "legs" (i.e., wires) are at 120V to ground, and 240V to each other. Just like 120V, each wire carries exactly the same current.

Mike

[Wade Lippman]

There is no concept of "per leg" in either 120V or 240V. There is just two wires, both of which carry the full current of the load.

Mike

Of course there is. A 120v 1hp motor has (approximately) 10a on 1 leg. A 240v 1hp motor has (approximately) 5a on each of two legs.

You are free to use any model that works for you, but there is nothing wrong with the one I like.