# Does a product see any difference from being powered by a single phase 240 V European outlet versus 240 V from a split phase 240V (120/120) US outlet?

I have seen similar questions and the answers always move on to the physics of the transformer and a center tap. I get all that, I think. My question is whether sophisticated electronics (specifically EV chargers) can tell any difference.

More succinctly, will a European car charger accustomed to receiving 240V over a single Line and Neutral react poorly (or even know) when connected to the US grid 240V over two 120V split phase Lines?

• US 240v supplies are not all the same as each other - sometimes it's across 2 phases of a 3 phase system. More here: youtube.com/watch?v=OiwWaIvIeao - a charger might be expecting a sine wave. In most of europe live and neutral can go either way round (i.e. you can put a plug in a socket 2 ways up) so I doubt a charger would be comparing neural and earth or anything like that
– Will
Nov 1, 2021 at 16:53
• @Will US 3 phase system is 120/208V. 240V can be used for european 220V device if it accept 240V. Nov 1, 2021 at 16:58
• As I understand it, if you use L1 and L2 in a three phase system, then you get 208v not 240? Nov 1, 2021 at 17:08
• @Alex Smith: In the US, 3-phase is mostly 480 V or higher. Three-phase 208/120 V is used in some commercial and residential buildings. Most residential and commercial services are 240/120 V split phase from an isolation transformer so that there is no direct connection to any 3-phase system. There is some 240V, 3-phase use. Many 480V, 3-phase motors can be reconnected for 240V.
– user80875
Nov 1, 2021 at 19:17

Yes, there is a difference, but another thing is if it matters and it depends on how the charger is built.

240 VAC single phase means one wire is neutral at 0V potential (bonded to earth/ground somewhere in the system) and the other wire is the 240 VAC live. The typical US household system means you also have 240 VAC but with center-tapped 0V neutral so you have two 120 VAC live wires.

So basically a simple device would not care how it receives 240 VAC but a more complex device could.

If the charger has a non-polarized mains plug then it must have been made so that which way the mains input live and neutral are must be irrelevant. If it is a fixed installation or has a polarized plug then it may matter which way live and neutral are connected.

So there can be no generic yes/no answer for any car charger you might mean.

• Most european plug is not polarized, Schuko for instance. And anyway or plug should be changed, or adapter used. Nov 1, 2021 at 17:01

The difference between a single-phase product made for Europe and that for the US (240V) would be as follows:

1. The input voltage: Europe - 230 V and US - 240 V.
2. The frequency: Europe - 50 Hz and US - 60 Hz.
3. The mains fuse: Europe - single fuse in line L and US - two fuses, one in line L1 and the other in line L2.

More succinctly, will a European car charger accustomed to receiving 240V over a single Line and Neutral react poorly (or even know) when connected to the US grid 240V over two 120V split phase Lines?

No charger would be capable of recognizing the difference.

The European charger would work normally in the US, provided the 240 V supply is within 230 V +/- 5%.

However, the additional fuse would need to be incorporated.

If you wanted the circuit to be able to tell the difference, you could have it measure the power frequency. European grids operate at 50 Hz, and North American ones at 60 Hz. Easy enough to tell the difference if you're trying.

If you're wondering if it'll actually affect anything, almost certainly not. Especially not with modern electronics; old equipment with mains-frequency transformers could have problems if operated at a lower line frequency than it's designed for, but modern equipment based on switching converters doesn't generally care what the mains frequency is.