120v/220v vs Straight "220v,208v etc.."

[combo52]

240 Volt and 208 Volt Power Supply

It is not one bit cheaper or more efficient to run motors on three phase 208 volt power, it is however cheaper to make a 3 phase motor of a given HP power and cheaper to wire it in to the power system.

 

There is NO 220 power in this country and it makes one appear very uninformed to even discuss such.

 

[kb0nes]

Variable Frequency Inverters

Three-phase induction motors have several advantages but energy conversion efficiency isn't one of them. The biggest advantage is starting torque and lack of extra required start components. They also tend to be smaller for a given horsepower as compared to single phase motors and have smoother torque curves over a wider frequency range.

The big game changer is that of variable frequency inverters. One of these coupled to a 3 phase motor allows for amazing control of speed, torque and direction. The use of a VFI can in many cases replace change gears and transmissions. We recently bought a new mid size CNC lathe at work, there is no variable gearing in the spindle drive at all. Just a 25 HP 3-phase motor and a variable frequency inverter drive. The lathe can run in either direction from 300-4000 RPM with almost no change in torque. It even ramps speed dynamically with changes in diameter and can reverse almost instantly for cutting with left-hand tooling!

One added advantage of the variable frequency inverter is that they can supply 3 phases from a single phase power. This can make for a economical way to run 3 phase motors in a home shop environment and additionally you can get some degree of speed control to boot!

 

[MrX]

Europe's confusing too!

Europe's slightly more standardised in terms of voltage than North America.

However, there are still quite a few differences in certain countries, even if there's more of a general consensus.

The voltage and frequency are totally standardised in the EU (and other surrounding countries). Australia and NZ also now followed suit too.

Voltage : 230V Single Phase / 400V Three Phase.
Frequency : 50Hz

Out of old habit, you will still get UK people referring to it as 240V (single phase) and 415V (three phase) and Irish/Continental People calling it 220V (single phase) and 380V (three phase).

The issues appliance makers face in Europe are more about plugs and sockets than voltages.

The vast majority of European countries (and many others) use the European CEE 7 system which has a socket outlet that delivers up to 16amps.

Then you've the UK, Ireland, Malta and Cyprus which use 13amp plugs

and a couple of countries that use 10A plugs.

So, appliance makers have to deal with different versions of the same appliance, especially dryers, for the countries that don't use 16A plugs.

So, drying times in the UK and Ireland are longer than in France, Germany etc with certain dryers where there might be a 16A version in France and a 10 or 13A version in the UK.

I know when we brought a dryer back to Ireland from France we had to change the socket outlet on the wall as it kept blowing the plug fuse.

Irish outlets are typically on 16 or 20Amp radials, but the plugs carry a 13amp fuse.

It was quite acceptable, legal and safe to install a 16A socket on that circuit.

The other thing in Europe is that many countries allow / encourage 400V 3-phase supplies to homes, while other countries, notably the UK and Ireland do not like that at all and encourage large single-phase supplies.
It's all a question of how the power company opted to balance its loads.

So, cooking appliances often come with options to connect them to various 3-phase hook-ups
Or, 230V 32amp circuits as found in Ireland and Britain for example.

So, it's always complicated no matter where you go I think!

 

[launderess]

When You Guys Are Right, You Are Right

Did some research and apparently at one time Miele has sold several flavors of those "splitter" boxes over the years.

One version fitted the standard four prong plug from the washer and dryer into it's outlets, however the plug on the splitter's cord was a *three* pronged 220v/60hz commonly found in some older homes, there was also a green wire with a terminal end leading out of the cable but not part of the plug. What one did was plug the thing into the 220v outlet and attached the terminal end via a screw to the outside of the outlet. The whole thing is similar to those old adapters sold to use things with three prong plugs (120v) with two pronged outlets.

Miele no longer stocks these sort of splitter boxes (I checked) but it confirms what many here have said. it is totally possible to wire and use a three pronged 220v plug and that the fourth doesn't "do" much related to the functioning of the machine other than ground and is tied off inside the machine somewhere.

Counterfeit UL Marking

Thanks for Norcal for finding this gem on E-Bay. I think it is safe to say that Neither UL, nor Miele, have ever seen this "product."

www.electrical-contractor.net

 

[launderess]

Oh And Another Thing

At least by the last incarnations of 220v powered washers (the 11XX and 12XX series) Miele used heaters with only 2100watts of power. While pushing things close to the windows edge you can eek out 2000 watts or so of power from a 120v/20amp circut IIRC providing the wiring can handle it and it does not go on for hours on end. Am wondering if it would then be possible to use a step-up converter to run a Miele washer off of. I mean if one doesn't plan on doing boil washes from ice cold tap water the other biggest draw would be the motor and on the series in question that only pulls 35watts.

 

[seamusuk]

Europe is standardised @230V?

In a word is it Heck.......
Was chatting to a guy from UK power networks a while back and mentioned our flat was getting 250v according to my voltmeter- he said the supply voltage is still 240-250v but the acceptable range has been altered on paper- whereas it was 240V-10/+5% its now 230+10/-5%.
He said if you think about it how would you change every transformer in such a short space of time for a 10v drop lol?
Seamus

P.S He also said another factor that makes a difference is how far you are from the substation that serves your building- as ours it literally over the road we are always going to get the high end of acceptable apparently......