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Fenix-Dark
11-27-2006, 02:35 AM
My father acquired some power tools that were intended to be used with the European 220 volt electric circuits, but we live in the States. We do have a few 220 volt electric circuits in the house (which are 2x 110 volt ones). I'm fairly certain that the US 220 volt circuits are 2 different sine waves, with a 1 radian phase shift difference between the two (so when 1 sine wave is at its peak, the other is at its trough(? think thats the word, bottom). In Europe they have different circuits that are just a sine wave that has a much higher amplitude.

Now getting to my point. Would my father's tools get damaged or possibly break if they are used on one of our 220 volt circuits?

Jon Gerow
11-27-2006, 11:52 AM
You are correct about the 2 vs. 1 sine wave.

What this does to power tools.... Good question! :D

I know a full sine wave will allow the motors to run cooler, but I'm not sure what two sine waves may do. Make the motors run hotter?

uOpt
11-27-2006, 01:57 PM
The house really has two phases of 110 just put on one wire? That's pretty crazy, IMHO.

I think it should be fine for many consumers including lights and most things with power supplies - but motors (including power tools) might have serious issues.

Why not get a transformer?

11-27-2006, 07:41 PM
My father acquired some power tools that were intended to be used with the European 220 volt electric circuits, but we live in the States. We do have a few 220 volt electric circuits in the house (which are 2x 110 volt ones). I'm fairly certain that the US 220 volt circuits are 2 different sine waves, with a 1 radian phase shift difference between the two (so when 1 sine wave is at its peak, the other is at its trough(? think thats the word, bottom). In Europe they have different circuits that are just a sine wave that has a much higher amplitude.

Now getting to my point. Would my father's tools get damaged or possibly break if they are used on one of our 220 volt circuits?

Most US 220v sockets, (Dryer/Electric Oven plugs?) are split phase, or basically two 120v lines, at least according to wikipeida...http://en.wikipedia.org/wiki/Split_phase

11-28-2006, 10:36 AM
I'm fairly certain that the US 220 volt circuits are 2 different sine waves, with a 1 radian phase shift difference between the two (so when 1 sine wave is at its peak, the other is at its trough(? think thats the word, bottom).

That would be a Pi/2 radian phase shift. In that case, one of 'em is a sine and the other is a cosine. ;)

You are right about the amplitude being higher everywhere else in the world. It could damage a rotary tool (unless the tool has a compensation mechanism in place), so I'd be careful. Note that most rotary hand tools may have a single phase motor. If it's a muti-phase motor, you would have no problems :)

Although I'm not 100% sure, I believe the single phase motor would heat up due to the jitter induced by two out of phase waveforms.

Fenix-Dark
11-28-2006, 08:34 PM
yup, I was wrong, i wasn't thinking straight, pi/2 radians = 90 degress, so its a pi/2 radian phase shift.

Any obvious signs on how to tell if the motor is single phase or multi-phase?

11-28-2006, 09:29 PM
Usually a 3-Phase unit will have 4 wires, Black, Red, Blue and White. You may need some kind of a NEMA arrangement though. I'm not very sure about this. :(

EsaT
12-20-2006, 12:55 PM
Most US 220v sockets, (Dryer/Electric Oven plugs?) are split phase, or basically two 120v lines, at least according to wikipeida...http://en.wikipedia.org/wiki/Split_phaseLet's see...
Two phase system with opposite phase (180 degree phase shift) wire in place of neutral produces sine wave with double voltage so that would fit to 220-240VAC tolerance of most European devices.
In three phase system (120 degree phase shift) voltage between two live wires is live to ground voltage multiplied with square root of 3. (400VAC here in Europe)

RPM of electric motors is dependent from frequency so that could be problem in some cases. Also there could be other problems.

ashiekh
10-26-2017, 07:38 AM
The difference between 2 Sine waves (of the same frequency) that are out of phase is still a sine wave, again of the same frequency, so long as the phase difference remains constant.

The frequency change (50->60Hz) shouldn't be a big problem for commutator based motors.

melpeffize
12-22-2019, 02:37 AM
Hello Jaehoon,

in addition to what Pasi said:
if you still have trouble with the sine test, please tell us what frequency you want to produce, and we will see how to generate the necessary parameters for it.

Kind regards,
- Henrik

gdjacobs
12-29-2019, 06:28 AM
The difference between 2 Sine waves (of the same frequency) that are out of phase is still a sine wave, again of the same frequency, so long as the phase difference remains constant.
Split phases are equal magnitude and 180 degrees out of phase. Each phase is the opposite pole of a transformer and the neutral is a center tap. The biggest potential issue is with earthing.

The frequency change (50->60Hz) shouldn't be a big problem for commutator based motors.
Indeed, universal machines won't have issues but induction motors may.

Jon Gerow
12-29-2019, 05:34 PM
Hello Jaehoon,

in addition to what Pasi said:
if you still have trouble with the sine test, please tell us what frequency you want to produce, and we will see how to generate the necessary parameters for it.

Kind regards,
- Henrik

You bumped a two year old thread.