# French Machine Requires 220V Single Phase to Ground



## telsa (May 22, 2015)

Wait till the gear shows up.

The tale your are hearing is likely to be entirely bogus.

( Typical non-electrician blather. )

Unless it involves VFD logic, it's a truly strange beast if it needs a grounded 220VAC -- at any Hertz.

VFD's -- almost uniquely -- need a grounded 'sink' for their power transistor logic.

All other loads are quite happy to live with ungrounded 208, 220, 240 VAC. (Typ.) They are just not that sensitive.

&&&

Power electronics and World Standard manufacturing have caused ALL of the Big Boys to standardize their stuff on ROBUST designs that can tolerate voltages and frequencies previously demanding clean conversion.

These days, even 'dirty power' is sufficient.

%%%%%

So, don't panic. Don't jump the gun.

WAIT until the gear shows up -- and then use the Internet to contact the factory to get the REAL scoop.

VERY, very likely, you don't have to sweat a thing.

$$$

Yes, there is a REVOLUTION in power electronics.

Google:

Voltage stacking

IGBT

And, for deep back ground:* DC impedance* -- the physics behind why your computer works.

{ DC impedance is TIME dependant. It decays to pure resistance within milliseconds -- in the typical power circuit.

{ Yet, digital, logical, circuits switch 1,000,000,000 times a second -- and much more.

{ THIS is why rectified AC can be dumped into capacitors -- and then creatively switched into AC at any number of frequencies -- or voltages.

!!!

Modern power electronics play with electrons like they are Play Doh.

And,... that's a fact, Jack !

This reality guts most of the 'truths' that we were all taught when we entered the trade.


----------



## Southeast Power (Jan 18, 2009)

thermoelectric said:


> I have a machine coming from Europe that I have to hook up. I am told that i need to supply 220v Single Phase. I know their voltage over in Europe is 220v to ground. Can I just use a single phase transformer and bond one of the secondary legs to ground? Just to be clear, they said that it would operate fine at 60Hz.


It shouldn't see "ground" related to any phase, you are bonding your equipment to "ground" 
You need to be able to feed it with the 240 or 208 you have and make sure that none of the control transformers are using "ground" to derive a control voltage.

I just went through this with some German and Itialian equipment that needed a NRTL label. None of them referenced ground for the controls. 
The owner of the plant set up a motor generator with a 50hz output. The ones that were not 3 phase just used phase to neutral just fine. No reference to ground required. 
When the equipment arrived, all of the motors and transformers were 50/60hz and just a few things needed to be changed like EVERY FREEKING CONTROL AND POWER CABLE. None of the cables had any writing on them much less any kind of UL/ CSA or anything like that. And the fuses. All of the small KTK and J type fuses had to be changed to ones with a listing.


----------



## MikeFL (Apr 16, 2016)

I'm in camp with those who say wait until the machine arrives, especially if you're getting info 3rd hand and/ or through a salesman.


----------



## wildleg (Apr 12, 2009)

thermoelectric said:


> I have a machine coming from Europe that I have to hook up. I am told that i need to supply 220v Single Phase. I know their voltage over in Europe is 220v to ground. Can I just use a single phase transformer and bond one of the secondary legs to ground? Just to be clear, they said that it would operate fine at 60Hz.


1) short answer: maybe

2) what the other guys said ^


3) best practice (when grounding phase is a fail): you can always use a 1:1 isolation transformer to achieve the "220 to ground" if it is absolutely necessary


----------



## MechanicalDVR (Dec 29, 2007)

I concur with waiting to see what you have when it arrives.


----------



## John Valdes (May 17, 2007)

220 is 220 any way you want to look at it. Don't lose any sleep over this.


----------



## Spark Master (Jul 3, 2012)

I do a lot of installations with European equipment. They ALL run perfectly fine with 208v 60 hz. Single phase & 3 phase equipment, and we have about 100 machines from Italy, some from China, and very few from the USA. The only thing different is the color code. Ground is green strip. and line is usually Blue/Brown.

Even the machines with 50hz motors run fine at 60hz. Never had a problem with a PLC machine either.


----------



## Southeast Power (Jan 18, 2009)

We had problem with the fuses not being listed and a few problems with the disconnects, OCP and motor overloads not being installed per US standards.

I will say that the machines we installed were for manufacturing aircraft parts. They were in a situation that somewhat forced them to install a 50hz motor generator just so they wouldn't have to defend themselves if there were ever a problem.


----------



## JRaef (Mar 23, 2009)

John Valdes said:


> 220 is 220 any way you want to look at it. Don't lose any sleep over this.


Correct. It's not really "220 to ground" in that even HERE, you don't have "120 to ground", you have 120 to NEUTRAL, and the NEUTRAL is referenced to ground. But that's not the same. The Neutral is referenced to ground AT THE DISTRIBUTION SYSTEM because it needs to be for safety reasons, but if there was no ground reference, 120V EQUIPMENT would still function just fine. The same is true "over there" in that their distribution system is always 380Y220V 3 phase, so the line to NEUTRAL voltage is 220V, and the Neutral MIGHT be referenced to ground, but not necessarily. So the EQUIPMENT (machine) will be designed to function based on the voltage reference from one line to the other line as being 220V, regardless of whether or not one of them is also referenced to ground in the distribution system that provides it. 

Over there, as it is here, you should NOT be bonding the Neutral to Ground INSIDE OF THE MACHINE. That's not to say it doesn't happen, hence the warning to CHECK IT OUT YOURSELF when it arrives. But it should be fine.


----------



## Spark Master (Jul 3, 2012)

JRaef said:


> Over there, as it is here, you should NOT be bonding the Neutral to Ground INSIDE OF THE MACHINE. That's not to say it doesn't happen, hence the warning to CHECK IT OUT YOURSELF when it arrives. But it should be fine.


 There is no neutral in the machine. :thumbsup:


----------



## JRaef (Mar 23, 2009)

Spark Master said:


> There is no neutral in the machine. :thumbsup:


Well, actually there probably WILL be a terminal _marked* _Neutral, but that should NOT be continuous to ground in the machine. That's the thing that needs to be checked.

* In a European designed machine, the incoming line terminals will likely be marked as L and N, but might also be U, V or W and N, with the N terminal being blue. U, V and W are their 3 phase designations, what we would mark as L1, L2 and L3. PE marked on a terminal means "Protected Earth" for them, what we call "Ground", using an insulated ground wire. So if you check for continuity from PE to N, there should be none. If there is, you will have to find the connection and change it (after determining why there is one inside of the machine).


----------

