Wiring up a 220V plug question

[Aaron Rosenthal]

Q 1) I took one of my many 16 Ga extension cords and decided to make it into a 220V unit, and ran into a situation.
The Leviton female portion has the 3 terminals marked the "proper" way: Brass, Silver and Green. However, the male part (PV 615) has only green, and 2 brass connection points. Does this mean that both poles are "live", and everything will work OK?

Q2) I have 2 robust tools from my 10 years in a 220V country - a electric plane, and a belt sander.
I had used the tools using a transformer, but What the heck, I have 220V in the workshop, so .....
The sander has a blue and brown wire. Only. No ground (earth). Can I wire any wire to either of the 2 spade plugs?

[Mike Henderson]

The power you have in your home will be 240 volts, not 220 volts. Personally, I would not use a 16 gauge extension cord - I'd at least use a 14 gauge. But if your power draw is low you're probably okay.

When you wire up for 120 volts, you have one hot, one neutral and one ground. When you wire up for 240 volts, you have two hots and one ground. In other words, use what would have been the neutral for the second hot.

Your 220 volt tool has two wires that will go to the two hots in your extension cord. Wire color doesn't matter.

Mike

[Aaron Rosenthal]

Thanks, Mike.
I'm wired up for 110/240(?) in the workshop - I'll re-look at the breakers.
It's ONLY to run my belt sander from the closest plug. I assumed with about a 5 amp draw, 16 might be OK, but I can wait until Tuesday to get some stouter wire.

[Clark Hussey]

Using an underrated gauge extension cord is asking for trouble. You need to use at least the same gauge wire as the cord leads other. With the 16ga. Cord you are asking for a fire.

[Andrew Seemann]

Remember that when you double the voltage, you half the amperage draw. That's kind of the point of higher voltage. The amount of amps that can go through a given wire size doesn't change, but you can raise the voltage and run more total power (watts) through it. That's why a 3 hp Unisaw running at 240V can use the same wire as a 1 1/2 hp saw running at 120V, and both use a circuit rated for 20A.

5 amps can go a long way through 16ga wire before voltage drop is an issue.

[Edward Dyas]

16ga. wire may be undersized for running machinery. It's harmful to a machine to use a too small a wire. The machine gets hot when starved for power. You can buy a length of larger wire at any hardware store and put plugs on it for an extension cord. You probably have 12 gauge wire at the receptacle. I would recommend using 12 gauge wire for the extension cord too. What is the amperage of the machine?

You are probably more familiar with 110v. There you have a hot wire (black), a neutral wire (white) and a ground (green). The motor itself doesn't need the ground, that is bonded to the machine for safety. A 220v motor doesn't use a neutral. It could run with only the two hot wires. The reason for this is it's alternating current meaning the two hot wires go from positive to negative and back. When one wire is positive the other is negative so that takes the place of the neutral. All that you need is to make sure the green wire that is bonded to the body of the machine is the ground on the plug. The two hot wires doesn't matter which is which.

[Aaron Rosenthal]

Thank you to all.
Although little draw, I'll grab 8' of 12 GA and re-do the extension cord properly.

[Mike Henderson]

Thank you to all.
Although little draw, I'll grab 8' of 12 GA and re-do the extension cord properly.

For the tools you mentioned, 14 gauge should be more than adequate. Make sure you get stranded wire and not solid wire. It'll be more flexible.

Mike

[John Lanciani]

Thank you to all.
Although little draw, I'll grab 8' of 12 GA and re-do the extension cord properly.

There is absolutely no need. 16 ga. SJ cord is rated for 13 amps at 300 volts. All the folks above that reccomended a larger cord need to do a little more research before they fire off incorrect answers. Asking for a fire, seriously? :confused:

[Jim Koepke]

Q2) I have 2 robust tools from my 10 years in a 220V country - a electric plane, and a belt sander.
I had used the tools using a transformer, but What the heck, I have 220V in the workshop, so .....
The sander has a blue and brown wire. Only. No ground (earth). Can I wire any wire to either of the 2 spade plugs?

My recollection is a bit rusty since it has been more than 20 years since working on European machines wired for 220V. If my memory is working in some systems one side of the 220V service was a neutral.

One thing to look at on the 2 spade plug would be if it has one spade larger than the other for polarization purposes. Many electrical hand tools are made with insulated bodies to get around the cost of having to have the cases grounded. These often are supplied with non-polarized plugs. Some have had plugs replaced and the ground removed.

So, you could be perfectly safe or you might electrocute yourself.

Most of the time my mess ups only cause a nasty shock or a few sparks and an unpleasant noise and/or smell.

Major Edit: Mike Henderson brought up my omission of stating both sides of a U.S. 220V plugs are hot to ground. Thanks Mike.

jtk

[Clark Hussey]

There is absolutely no need. 16 ga. SJ cord is rated for 13 amps at 300 volts. All the folks above that reccomended a larger cord need to do a little more research before they fire off incorrect answers. Asking for a fire, seriously? :confused:

Yes 16 gauge is good for 13 amps. But why would you chance it. I just checked all my 220 volt machines and not one of them has a 16 gauge wire on it. They are all 14 or 12 gauge wire. Maybe the manufacturers know something. I’m sure if they could save a couple dollars per machine by using 16 gauge they would. Probably has something to do with people putting their machines under heavier loads than they are designed for. I would much rather be safe than sorry at the cost of a couple dollars.415370

[Mike Henderson]

My recollection is a bit rusty since it has been more than 20 years since working on European machines wired for 220V. If my memory is working in some systems one side of the 220V service was a neutral.

One thing to look at on the 2 spade plug would be if it has one spade larger than the other for polarization purposes. Many electrical hand tools are made with insulated bodies to get around the cost of having to have the cases grounded. These often are supplied with non-polarized plugs. Some have had plugs replaced and the ground removed.

So, you could be perfectly safe or you might electrocute yourself.

Most of the time my mess ups only cause a nasty shock or a few sparks and an unpleasant noise and/or smell.

jtk

You're partially correct, Jim. In Europe 3 phase is brought to the street and the transformer is wired as a Y. The 220 volts (note: not 240 volts as in the US) is taken from the center (ground) and one outside wire. So one side of that power is grounded. (also note: The UK is different - it has 240 volts and 415 volts, while Europe has 220 volts and 380 volts.)

But the US is different. Power is supplied from a single phase transformer with a (grounded) center tapped 240 volt secondary. So the two outside wires on the secondary are both hot compared to ground.

When wiring up a 240 volt circuit in the US, both wires are hot with 120 volts (each) to ground and 240 volts between them.

People have had a lot of arguments about which system is best. The US system is certainly safer because there's only 120 volts to what you're standing on, while in Europe there's 220 volts to what you're standing on.

But 220 volt power provides some advantages, especially where the current limit of most 120 volt systems becomes a problem. Toasters could get hot quicker, coffee makers could start making coffee quicker, vacuum cleaners could be more powerful, etc. But many of the newer products, such as TV, charges for cell phones, etc. require very little power so going to 220 volts doesn't provide much advantage.

Personally, I'd prefer having 220 volts everywhere in my house, and 220 volt appliances - but that's just me.

Mike

[P.S., I agree with Clark, above. While 16 gauge extension cord will work, it's generally considered small for an extension cord. I'd go with 14 gauge so that if I wanted to use it for something different in the future it would be okay. The problem with 12 gauge is that the cord gets fairly big.]

[Frank Pratt]

There is absolutely no need. 16 ga. SJ cord is rated for 13 amps at 300 volts. All the folks above that reccomended a larger cord need to do a little more research before they fire off incorrect answers. Asking for a fire, seriously? :confused:

What John said. I'll add that when running a load at 240V, the percent voltage drop will be 1/4 what it was at 120V. And for an 8' cord, inconsequential. OP didn't state what the rated loads of the tools are, but for a hand held planer or sander, it's probably in the range of 5A - 8A at most.

It never fails to astound me at the misinformation that is posted in almost every electrical thread.

[Jim Koepke]

Mike thanks for clearing up my musings that could otherwise be misleading. Yes, in the U.S. power distribution system both sides of the 208-240V supply is hot to ground.


I’m sure if they could save a couple dollars per machine by using 16 gauge they would. Probably has something to do with people putting their machines under heavier loads than they are designed for.

One reason for using heavier gauge wire on equipment is if their is a problem the wiring can handle the current needed to open a breaker or fuse before the wire heats up and starts a fire.


It never fails to astound me at the misinformation that is posted in almost every electrical thread.

This and the danger people can get in to with a simple error is my reason for being careful about joining such conversations. Even my comment above could have been misleading.

jtk

[John Lanciani]

One reason for using heavier gauge wire on equipment is if their is a problem the wiring can handle the current needed to open a breaker or fuse before the wire heats up and starts a fire.


jtk

Take a look around your house Jim, I guarantee that there is a lamp or clock or some such with an 18 ga cord plugged into a circuit protected with a 15 or 20 amp breaker.

[Jim Koepke]

Take a look around your house Jim, I guarantee that there is a lamp or clock or some such with an 18 ga cord plugged into a circuit protected with a 15 or 20 amp breaker.

My comment was offering one reason to use an adequate gauge of wire in a circuit. It is to my knowledge not a matter of code or law.

In my experience more home shop and contractor equipment has created a display of smoke or fireworks than lamps or a standard wall clock.

jtk

[Kev Williams]

I know the differences between 120 and 240, but I could use an explanation as to why a 5000 watt hot tub heater with both ends connected to 120 volts becomes only a 1250 watt heater with one end connected to 120 and the other end neutral... simple question, why is the wattage quartered and not halved?

and-- won't this answer apply to the 16ga wire debate?





.

[Frank Pratt]

I know the differences between 120 and 240, but I could use an explanation as to why a 5000 watt hot tub heater with both ends connected to 120 volts becomes only a 1250 watt heater with one end connected to 120 and the other end neutral... simple question, why is the wattage quartered and not halved?

and-- won't this answer apply to the 16ga wire debate?

This calls for a little math:
First, let's look at the operation at 240V. For a 5000W heater we need to figure out the current and resistance of the element.
To find circuit current: 5000W ÷ 240V = 20.83A
To find element resistance: 240V ÷ 20.83A = 11.52Ω
Now we'll connect that same heater to 120V:
Current: 120V ÷ 11.52Ω = 10.42A
Watts: 120V X 10.42 = 1250.4W

[Mike Henderson]

This calls for a little math:
First, let's look at the operation at 240V. For a 5000W heater we need to figure out the current and resistance of the element.
To find circuit current: 5000W ÷ 240V = 20.83A
To find element resistance: 240V ÷ 20.83A = 11.52Ω
Now we'll connect that same heater to 120V:
Current: 120V ÷ 11.52Ω = 10.42A
Watts: 120V X 10.42 = 12650.4W

Typo in your last line. Should be =1250.4W

Mike

[Frank Pratt]

Typo in your last line. Should be =1250.4W

Mike

Thanks Mike :eek: It's corrected.

[Jim Koepke]

I know the differences between 120 and 240, but I could use an explanation as to why a 5000 watt hot tub heater with both ends connected to 120 volts becomes only a 1250 watt heater with one end connected to 120 and the other end neutral... simple question, why is the wattage quartered and not halved?

and-- won't this answer apply to the 16ga wire debate?
.

It depends on the way the heater elements are designed. If there are two elements with only one of them having a center tap to allow for a 120V connection, that would explain it.

At half power, 2500 watts, it would be slightly above the limit for a 20 amp breaker in a 120V circuit.

jtk

[Frank Pratt]

It depends on the way the heater elements are designed. If there are two elements with only one of them having a center tap to allow for a 120V connection, that would explain it.jtk

The hypothetical heater in question would behave as discussed if it was just a simple single element heater. If you half the voltage, you get 1/4 of the full voltage heat.

[Curt Harms]

One other thought about European motors - what's the frequency? I recall discussions about European induction motors running at 50 Hz. I don't know if that matters to the machines in question or not (universal motors don't care I think).

[Mike Henderson]

One other thought about European motors - what's the frequency? I recall discussions about European induction motors running at 50 Hz. I don't know if that matters to the machines in question or not (universal motors don't care I think).

At full load a European 50hz two pole induction motor will run a bit less than 3,000 RPM (2,850 RPM), just as a 60hz two pole induction motor will run a bit less than 3,600 RPM (3,450 RPM). Because the European motor runs at a lower hertz it will normally have more steel in the stator. Normally, you can run a 50hz motor on 60hz without any problems. You may encounter problems (overheating) going the other way, running a 60hz motor on 50hz.

Mike

[But a European power tool may have pulleys that are calculated to turn a saw blade at a certain speed. If all you do is run the tool at 60hz you may be overspeeding the saw blade.]