Going from 110 volt to 220 volt

[Rick Huelsbeck]

When I get my shop done (Saturday if all goes to plan :D) it is going to have enough circuits to run my equipment that will run on 110 or 220, to be used on 220. I really hate cutting off plugs and putting on new plugs. I just don't feel safe doing it even though I know it is. So 2 things come to mind, All new cords with plugs designed to go into 220 outlets, or do they make an adapter for plugging the 110 volt male plug into that can then be plugged into then 220 outlet. I would prefer the cord method, but that can be expensive.

If anyone has a source for either I sure would appreciate that.

[Cliff Holmes]

You might want to reconsider doing it at all. The benefits of 220 vs 110 are minimal at best.

[Roger Jensen]

I predict you'll become comfortable changing plugs and cords in the very near future! :)

Obviously, there is more to it than just changing the plug to go from 110 to 220. You should come up with a strategy for which plug type you're going to use, and the size cord you need (depending on length and amp requirements).

You don't want an adaptor for a 110 plug. You'll have to rewire the cord to the tool (you can't use the same wiring setup you have for 110), and you don't want to accidentally plug it into 110 after you have made the change.

As Cliff has mentioned, you don't want to do it just to do it. I only run 220 on two tools, my Hammer J/P and my SawStop TS. They only run on 220.


Roger

[Ken Fitzgerald]

The cheapest method is to put 220 plugs on existing cords and it's really not that difficult.

As others have stated though, there really is no great benefit. There are a lot of misinformation about this out there as to the benefits.

I built a new shop 5 years ago. I installed a separate meter and 200 amp service. I have plenty of 220 and 110 outlets. My new lathe and my bandsaw require 220vac and those I have wired for 220. My table saw still remains at 110 vac. I have plenty of outlets at both voltage levels.

[Jamie Buxton]

.... I really hate cutting off plugs and putting on new plugs. I just don't feel safe doing it even though I know it is. ..

You do understand that you must convert each machine to 220? Generally, you must open cover plates and move wire connections inside each motor. If you feel comfortable doing that, changing plugs should be a piece of cake.

[Ken Fitzgerald]

You do understand that you must convert each machine to 220? Generally, you must open cover plates and move wire connections inside each motor. If you feel comfortable doing that, changing plugs should be a piece of cake.


OH YEAH! That minor detail too!

[Rick Huelsbeck]

I know I have to re-wire the motor, and the primary benefit for me is I will not need to pull as many amps/circuits. I'm going to do a 100 Amp sub-panel off of the main. I have 4 pieces of equipment that can run on 220. At 220 vac I will pull 7 amp at the most where as with it a 110 I'm going to pull 15 or more. I will only need 2 circuits at 220 vac 20 amp circuits where as with 110 I'm going to need 4 110 vac 20 amp circuits.

Currently I'm running a 3/4 hp lathe and well I'm starting to get the itch for bigger since I'm going to have more room so 220 vac is in the future anyway :D.

[Darius Ferlas]

I made myself 2 one foot extension cords that allow me to use the 110 plug that came with the machine. The extension cord will accept that one one end and it will plug into a 220 receptacle on the other. So far, upon further investigation and after learning a lot from this forum, I haven't had the need for them.

As others said, in some cases going to 220 is art for art's sake. I have Ridgid TS that uses 13 amps @ 110 and I could feel how it wasn't all it could be on a 15 am circuit. I upgraded the circuit to 20 amps and it runs as well as it would on 6.5 amps @ 220.

I only used 220 for machines where the amperage they use would go to close to the 75% (?) of the allowed/recommended load for the circuit to which they are connected.

[Mitchell Andrus]

If you have the opportunity, you might as well run a few. This will leave your tool buying options open to a greater range later.

As to 220V plugs.... they are made to avoid accidentally overloading a circuit. A plug on a tool that draws 20 amps shouldn't be plugged into a circuit designed to deliver 15 amps. The spades are different and are marked for the max amps the circuit is designed for and changing the outlet to fit the plug is a no-no. 15 amp wire, 15 amp female, 15 amp male on a <15 amp tool. Run the circuits so you don't overload them. 20 and 30 amp circuits are the norm.

Google difference between 110 and 220 for more.
.

[Steve Milito]

I made myself 2 one foot extension cords that allow me to use the 110 plug that came with the machine. The extension cord will accept that one one end and it will plug into a 220 receptacle on the other. So far, upon further investigation and after learning a lot from this forum, I haven't had the need for them.



I think that is dangerous. The whole purpose of having different receptacles is to prevent you from plugging a 110v appliance into a 220v receptacle. Not only can it cause a fire, but it also may potentially energize the chassis causing a shock hazard.

[Prashun Patel]

I just finished rewiring my jointer for 220. It's easy. Get a good plug with screw down clamps; you can use the existing cord. Then your manual will have a diagram of how to switch the wires in the motor or switchplate. I think that's more 'safe' than finding a retrofit plug.

As far as the benefit of 220 over 110, I've concluded that there is a benefit to improved motor life due to less strain at higher loads or long lines. However, contrary to popular belief, there is no power consumption savings.

[Darius Ferlas]

I think that is dangerous. The whole purpose of having different receptacles is to prevent you from plugging a 110v appliance into a 220v receptacle. Not only can it cause a fire, but it also may potentially energize the chassis causing a shock hazard.
It certainly is dangerous to connect 110 equipment to a 220 circuit, and perhaps even illegal in a somewhat more formal environment. No arguing there.

For my one man gang shop setup the idea was not to chop original plugs off and being fully aware what gets connected to what, all receptacles clearly marked. As I wrote, I never used those little extensions and they sit in the drawer somewhere. Your response is much appreciated though. It actually gave me a reason to find those extensions and dismantle them, in case someone unaware of what the're looking at lays their hands on them.

[Don Jarvie]

220 becomes valuable when you get larger motors with more HP. Some of the older 3hp motors draw over 25 amps at 110 so with 220 you cut that in half.

220 also allows you to use smaller wires - 12 g will run 220 with a 20a double breaker. If your going to use a large motor on 110 you need to use 10g or if the motor is really big 8g.

Also, 220 will draw less current so if you are using a DC and the TS at the same time 220 will cut the total amps in half. This is good if you are only pulling 40 or 50 amps total in the panel for the shop.

Rewiring the motors and putting on new plugs is easy to do.

[Scott Holmes]

NOTE: Not all 120V motors can be rewired to 240V.

FYI it's been 120V & 240V in the USA since just after WW II

[Chip Lindley]

The 120v/240v thing has been debated to death here!

If a machine needs to be run on 240v, IT WILL TELL YOU! Breakers trip! Motors overheat and trip their reset button!

If motors spin up to speed instantly on 120v without making the house lights flicker, and perform as expected, all is well. Otherwise....consider converting to 240v.

[Rick Huelsbeck]

NOTE: Not all 120V motors can be rewired to 240V.

FYI it's been 120V & 240V in the USA since just after WW II

I guess most people here don't know I worked as an electrician at one stage in my life. I've also been a steam plant mechanic (millwright in the civilian world), aspired to be an auto mechanic at one time, and done general construction. Computer programming is sure a lot easier way to make a living (most times anyway :D)

Ok, having said that, I can see adapters are a bad idea, does anyone have a source for power cords? Yes, I can cut the original cords and add a plug on it, I've done that in the past too. I'm a funny kind of person and like the look of a continous molded plug on my cords.:p

[Chip Lindley]

I'm a funny kind of person and like the look of a continous molded plug on my cords.:p

I just found you an 8' long L6-30 molded cord on eBay for only $33.00! But, you still have to cut the computer connector off one end and strip the wire.
http://i822.photobucket.com/albums/zz142/zzarus/L6-30moldedcord.jpg
I guess that won't work.

The only other common "continuous molded plugs" I have seen for 240v are 30A dryer cords and 50A range cords. (most are only 4 feet long)
http://i822.photobucket.com/albums/zz142/zzarus/Dryercord30A.jpg
Those are a bit tacky IMO for woodworking machinery.

I'm a bit funny too. I like the look of Hubbell L6-30 plugs on the ends of my 240V equipment, but I "roll my own!"
http://i822.photobucket.com/albums/zz142/zzarus/HBL2621.jpg

[Dan Hintz]

Meh, just throw some quality shrink wrap around that end and get the faux-molded look ;)

[Hugh Jardon]

You should not be able to find an adaptor, since that would also allow the user to plug a toaster into a 240V outlet, and that would be a BAD THING.

I think there's a lot of misinformation about the benefits of moving from 120 to 240, and it can offer some great benefits to the user, but it all depends on where you are starting from.

It doesn't sound to me as though you would see a great benefit, if you are putting plenty of 120 circuits in to begin with. As long as that is circuits, not receptacles on the same 120 circuit.

On the other hand, if moving to 240 would force you to put in more circuits, and you currently are marginal on the current at 120, then it's a clear winner. Another 120 circuit would help, but not if it's a long run so much as 240.

I squared R loss is not in favor of 120 as much as 240.

Everything I have (that is capable of conversion) is 240, and I have not bogged anything yet, nor tripped the lights, and it was a daily occurrence before I committed to 240. I can also share a single 240 circuit between tools, and that was exactly my issue previously.

Go 240 and don't look back.

[Don Jarvie]

I've rewired every machine I have restored so I can lengthen the cord. I buy the SWO type rubber cord at HD or Lowes in whatever size I need.

Add a new plug and wire it to the motor. The rubber cord is much more pliable than the replacement cords. Only extra cost is buying the plug.

[Lee Schierer]

I know I have to re-wire the motor, and the primary benefit for me is I will not need to pull as many amps/circuits. I'm going to do a 100 Amp sub-panel off of the main. I have 4 pieces of equipment that can run on 220. At 220 vac I will pull 7 amp at the most where as with it a 110 I'm going to pull 15 or more. I will only need 2 circuits at 220 vac 20 amp circuits where as with 110 I'm going to need 4 110 vac 20 amp circuits.


With 220 you actually get fewer circuit breakers in the same panel by 1/2 so you end up with fewer total circuits. Unless you plan to run all the tools simultaneously you should be able to get 18-20 circuits from a 100 amp panel box. The box is sized for total load it will handle there may be more than 100 amps if you total the breaker ratings. If the total load exceeds the rating of the panel the panel main will trip.

[Rick Christopherson]

You should ......I thought this forum required people to use their real names.

[Karl Card]

One of the wood working mags I have did an article on 120 vs 240. They pretty much said no difference. I would have to say that "I really dont know".... But I will say this, I will take a 220 volts AC window unit any day of the week before a 110 unit. I have never had a 220 volt ac use more juice than a 110 volt. I dont know if that is just because of dealing with compressors over an electric motor or what... but have seeen the difference. As far as my other stuff, my air compressor runs on 220 and has to be hardwired. my band saw can be 110 or 220 and it still runs at 110. my jointer/planer is 220 and I was shocked when my drum sander is only 110 but it seems to do ok...it is a 16/32.

I have had some of the locals here say that they cant prove it thereself but feel a motor runs more effeciently at 220 than 110 causing it to last longer... I dont know, they dont kow but they just do what makes them feel good.... what else can you say.

[Dan Hintz]

If by "efficient" they mean (a tad bit) cooler, then yes, it's more efficient. As has been posted on other threads about this topic, you are still using the same amount of power regardless of what voltage you choose to use. Since power usage, not voltage or amperage, is what the electric company charges you for, that's what matters.

This all assumes you have used thicker gauge wire (which costs more money) run to the appliance if you're running 120V to remove the extra resistive losses at the higher current levels. Tools wired for both 120/220V have internal wiring spec'd for 120V, but they'll run a bit cooler at 220V, again because of the resistive losses.

[Rick Christopherson]

Tools wired for both 120/220V have internal wiring spec'd for 120V, but they'll run a bit cooler at 220V, again because of the resistive losses.No they don't. The internal windings in the motor see exactly the same current and voltage regardless how they are configured. Each winding sees 120 volts. In one configuration they are in parallel (120 volt) and in the other they are in series (240 volt).

[George Clark]

If you double the voltage you cut the current in half. Does that not reduce the heat and thus increase the efficiency and the life of the motor? Is heat not the enemy of an motor? If it is not, why do motors have fans? :confused:

[Dan Hintz]

D'oh, you're right, Rick... this is why I never received more than a 'C' in my power engineering courses... hated then, hate it now, will more than likely hate it tomorrow.

[Ken Fitzgerald]

Regardless of the applied voltage, the total power consumed by the load (in this case the machine) is the same and thus the heat generated would be the same.

[Dan Friedrichs]

If you double the voltage you cut the current in half. Does that not reduce the heat and thus increase the efficiency and the life of the motor? Is heat not the enemy of an motor? If it is not, why do motors have fans? :confused:

It would, except when you re-wire a motor to convert it, you change the series windings to parallel, so the motor sees exactly the same thing.

[Rick Christopherson]

If you double the voltage you cut the current in half. Does that not reduce the heat and thus increase the efficiency and the life of the motor? Is heat not the enemy of an motor? If it is not, why do motors have fans? :confused:No. From Ohm's Law, when the voltage increases, the amperage also increases proportionally. What you are not seeing is that the circuit path (inside the motor) has also changed, which impacts the total impedance of the motor as seen by the supply circuit.

The diagram below explains why the total amperage from the supply circuit is reduced at the higher voltage, but also why the internal amperage within each winding remains the same.

http://www.waterfront-woods.com/tempgraphics/splitwinding.jpg

If you change the voltage to the motor without reconfiguring the windings (240 volts in the 120 volt configuration), then you will see the amperage to the motor double instead of cut in half.

[ray hampton]

is it okay for a stupid question, if 220 volts cable are 3 strands of copper ,where is the ground wire ?

[Chip Lindley]

I'll stick my neck out....(concerning motors)

240v (aka 220v) cable has black/white/red instead of green. Black/Red are 120v conductors and white is ground (not neutral) A connection to neutral in your load center is not needed for 240v electric motors.

[Rod Sheridan]

is it okay for a stupid question, if 220 volts cable are 3 strands of copper ,where is the ground wire ?

Hi Ray, normal flexible cord in three conductor will have a black, white and green conductor.

For 120 volts the black is line 1, the white is neutral, and the green is ground.

For 240 volts the black is line 1, the white is line 2, and green is ground.

Regards, Rod.

P.S. Generally 240 volt single phase machines don't need a neutral as there aren't any 120 volt devices on them.

[ray hampton]

Hi Ray, normal flexible cord in three conductor will have a black, white and green conductor.

For 120 volts the black is line 1, the white is neutral, and the green is ground.

For 240 volts the black is line 1, the white is line 2, and green is ground.

Regards, Rod.

P.S. Generally 240 volt single phase machines don't need a neutral as there aren't any 120 volt devices on them.


is line 1 120 volts or 240 volts ?
is line 2 a return line[also know as a neutral line ?
if 240 volts do not need a neutral then do the voltage go to ground after it do its work ?

[Ken Fitzgerald]

is line 1 120 volts or 240 volts ?
is line 2 a return line[also know as a neutral line ?
if 240 volts do not need a neutral then do the voltage go to ground after it do its work ?

Ray,


In most 240 vac operations:

Line 1 is 120 .....Line 2 is 120.....current flows from line 1 to line 2 and visa versa. The 2 - 120vac lines are out of phase so current flows from one to the other.

Line 3 is ground and is there for a safety but current should not be going through or to it.


Unlike 120 vac operation, neutral is rarely used in 240 vac operation.


In 120 vac operation:

Line 1 is 120 vac.....the white is neutral and current flows from 120 vac to neutral. Green is ground and normally there should be no current flowing through ground.

[Mike Henderson]

is line 1 120 volts or 240 volts ?
is line 2 a return line[also know as a neutral line ?
if 240 volts do not need a neutral then do the voltage go to ground after it do its work ?
When you ask whether one line or the other is 120V, you have to specify in reference to what.

In the US, each line of a 240V line is 120V referenced to ground, and 240V referenced to each other.

The current (not voltage) does not go to ground, it goes back to the source.

Mike

[ray hampton]

the source is the transformer 50 feet from the home, if the current and voltage travel from the home to the transformer, will it travel out the other transformer line ? [single phase ]

[George Clark]

No. From Ohm's Law, when the voltage increases, the amperage also increases proportionally. What you are not seeing is that the circuit path (inside the motor) has also changed, which impacts the total impedance of the motor as seen by the supply circuit.

The diagram below explains why the total amperage from the supply circuit is reduced at the higher voltage, but also why the internal amperage within each winding remains the same.

http://www.waterfront-woods.com/tempgraphics/splitwinding.jpg

.


Rick, The Ohm's Law that I was referring to is P=EI; with the power remaining constant any increase in voltage causes a proportional decrease in amperage. Thus, I don't understand your first sentences.

With that being said, I obviously also didn't understand what was happening internally when a motor was converted from 120V to 240V. Thanks for your explanation. Let's see if I have a better grasp if the facts now.

As long as the motor can run on the typical 120V 15 amp (or 20 amp) circuit there is no advantage to be gained, as far as the motor is concerned, by converting it to 240V because the current through the individual windings remains essentially the same even though the supply current is cut in half. As the power of the motor increases, running it on 240V allows the use of the same gage wire that the typical 15 amp 120V circuit uses by reducing the supply circuit current, at least up to a point. Obviously, at some point power requirements will require a larger gage supply wiring.

Thanks to all who responded.

George

[Rick Christopherson]

Rick, The Ohm's Law that I was referring to is P=EI; with the power remaining constant any increase in voltage causes a proportional decrease in amperage. Thus, I don't understand your first sentences.George,
Everything about your posting was correct, except for Ohm's Law. Ohm's Law is V=I*R. The power equation you stated is correct, but it is not called Ohm's Law.

In most cases, when the voltage of a circuit is changed, the power changes proportionally. The only way for the power to remain constant with a changing voltage is to have a changing resistance. In this case, the change in resistance is when the coils are rearranged from parallel to series.

[ray hampton]

George,
Everything about your posting was correct, except for Ohm's Law. Ohm's Law is V=I*R. The power equation you stated is correct, but it is not called Ohm's Law.

In most cases, when the voltage of a circuit is changed, the power changes proportionally. The only way for the power to remain constant with a changing voltage is to have a changing resistance. In this case, the change in resistance is when the coils are rearranged from parallel to series.

if the size of the cables are 12 gauge and you switch to 6 gauge --will the resistance change ?
how many formulas are there for figuring watts

[Dan Hintz]

Ray,

There are two equations that will help you get through life:
P=IV (Power = Current x Voltage)
&
V=IR (Voltage = Current x Resistance)

Mix and match them, as appropriate to the situation. For example, P=(I^2)R if I know the winding resistance and current and I want to know the power consumed.


A halving of gauge is a doubling of wire diameter... which is a quadrupling of the wire cross-sectional area, and a quartering of the resistance. 6 Gauge wire is a beast compared to 12 Gauge. If 12 Gauge is rated for 20A service, 6 Gauge would be rated (nominally) for 80A (not including any local derating).