240 split phase vs 230v European inverter and US split phase devices

[Watts Happening]

Seemingly a dumb question here, but I don't know the answer.

Let's say you have a US based 240v split phase air compressor, or mini split, or clothes dryer etc. Clearly you can use a pair of 120v inverters in split phase, I totally understand that.

Now my question is, would a 230v Victron (or equivalent) that will allow you to switch to 60hz work with the above devices?

The real thing I'm trying to understand here, is, does a split phase device "know" or "care" if it's getting 120v on two phases that are 180 degrees out of sync vs getting 230v on a single phase? The voltage isn't the question to me, it's whether or not the traditional devices can really tell any difference there in potential or if they would fire right up and be happy?

 

[FilterGuy]

The answer is 'maybe'.

Most US 240V devices don't use the center tap neutral. However, there are a few that do. The ones that use the center tap neutral will probably not work on a 230v Victron.

WARNING......If you use a Victron 240V, non-north American inverter, One of the two lines will be neutral, and when in battery mode the neutral will be bonded to ground which is also connected to the case of the inverter. (Just like they do in Europe). This is all fine as long as your system is totally isolated from any US-Grid. If you tie the US grid to the AC input of the inverter, things can get wonky. In battery mode one of the lines is neutral but in passthrough mode neutral is something different. This could possibly be made to work, but I would highly recommend against it.

Bottom line: You could probably make it work, but I would not try to use a 240V euro inverter in the US.... the neutrals are just enough different that it is asking for trouble. When in Rome, do as the Romans do. When in America, do as the Americans do.

 

[Ampster]

The answer is 'maybe'.

I agree that some devices may work, but the real issue may be the bui.ding code allowing the neutral on one of the 240 Volt legs. Not to mention the Neutral/Ground issues.

 

[BentleyJ]

What FilterGuy and Ampster said is good advice. You cannot have one of the hot legs connected to ground.
I would just add that many US based appliances, like AC condensers (the ones with 2 hot wires and ground, no neutral) are designed to work with either 208V or 240V. So theoretically would work fine with 220V or 230V. Your compressor motor may have different wiring taps inside the cover for alternate voltages. Usually these details are printed on the motor label.

 

[CoolWill]

A 240 volt-only machine, like an air compressor, will work just fine. But a clothes dryer won't because most of them are what's known as 120/240 V, meaning that some parts of the machine require 120 volts in addition to 240 volts. Clothes dryers and ranges are generally 120/240 and require a neutral to supply 120 volts to things like lights and timers, but also need 240 volts for the heating elements.

 

[timselectric]

240v split phase air compressor, or mini split, or clothes dryer etc.

Now my question is, would a 230v Victron (or equivalent) that will allow you to switch to 60hz work with the above devices?

No
Not if they require split-phase.
Unless you add a transformer.

 

[Watts Happening]

Thank you for the responses, I should clarify that I’m not actually trying to do this, was just wondering how it would work in theory.

Thanks!

 

[1201]

No
Not if they require split-phase.
Unless you add a transformer.

So a 240v only load(L1,L2,GROUND) can't be powered by a UK 230V inverter(L,N, GROUND) ?

 

[Crowz]

I cant see how it would work and every 240v device I have uses 120 for something.

Dryer is 120v for the drum motor and fan.

My ac units only use 240v for the compressor and the rest is 120v for fans and electronics.

etc.

 

[Crowz]

I just remembered one thing I have thats 240v only and thats the hot water heater

 

[Hedges]

240V only units would generally work with either single-phase 220V or split-phase 240V.
Circuit breakers designed for 120V (single pole) and 120/240V (double pole) often are not rated to interrupt 240V with a single pole, although some are.

 

[1201]

I just remembered one thing I have thats 240v only and thats the hot water heater

My 240v only loads are
3x heat pumps
Water heater
Well pump

And a 5kw 230v inverter would run all my heat pumps

 

[zanydroid]

230V only will work fine with international appliances released in the US with minimal changes. I have a 240V wall oven like that, and one out of five heat pump dryers I’m looking at does not need neutral either.

A lot of mini splits are 240V only as well (both outside and inside unit).

I also have one 240V countertop kitchen cooker that’s basically an AliExpress special. Actually a lot of commercial cooking appliances are 208/230/240

 

[1201]

240V only units would generally work with either single-phase 220V or split-phase 240V.
Circuit breakers designed for 120V (single pole) and 120/240V (double pole) often are not rated to interrupt 240V with a single pole, although some are.

Thanks.

So I can use a 230v European inverter to power my inverter heat pumps that say "240v - 1 phase - 60hz"

Thats great to know.

So let me complicate it a little - would same said European inverter accept u.s 240v ac input?

 

[1201]

230V only will work fine with international appliances released in the US with minimal changes. I have a 240V wall oven like that, and one out of five heat pump dryers I’m looking at does not need neutral either.

A lot of mini splits are 240V only as well (both outside and inside unit).

I also have one 240V countertop kitchen cooker that’s basically an AliExpress special. Actually a lot of commercial cooking appliances are 208/230/240

So do you mean basically any 240v appliance that only uses 3 wires?

 

[timselectric]

So a 240v only load(L1,L2,GROUND) can't be powered by a UK 230V inverter(L,N, GROUND) ?

It would depend on the actual piece of equipment.
And if it was made for North American split-phase, or not.
Without a transformer, you wouldn't have a split-phase ground.
Could I make something work in an emergency situation, yes.
Would I leave it this way permanently, absolutely not.
Someone else might get hurt.

 

[1201]

It would depend on the actual piece of equipment.
And if it was made for North American split-phase, or not.
Without a transformer, you wouldn't have a split-phase ground.
Could I make something work in an emergency situation, yes.
Would I leave it this way permanently, absolutely not.
Someone else might get hurt.

What do you mean that " without a transformer you wouldn't have a split phase ground"?

Do you mean an autotransformer? Why would one need an auto transformer for ground?

 

[timselectric]

Why would one need an auto transformer for ground?

You have to create the grounding system.
In a North American split-phase system, it's created at the N/G bond.
In a European single phase inverter. The neutral would be used as the North American L2. Creating the grounding system from L2 could get someone hurt. And any equipment that requires a ground would be dangerous.

 

[1201]

You have to create the grounding system.
In a North American split-phase system, it's created at the N/G bond.
In a European single phase inverter. The neutral would be used as the North American L2. Creating the grounding system from L2 could get someone hurt. And any equipment that requires a ground would be dangerous.

Ok let me understand -

Euro inverter is sending power to a usa 240v load via L,N

Euro inverter has neutral bond to ground.

Under normal operation ground carries no current since the power is flowing from l1, through the load, and back to the inverter via neutral.

Let's say load is a USA 240v water heater and everything is working as normal.

Now, if L1 from the euro inverter somehow touches the metal case of the USA water heater, the 240v from the inverter will flow through the grounded metal case of the water heater, via the ground wire, to ground ,BUT since ground and neutral are bonded at the inverter, it will ultimately complete it's normal course of flowing back to it's source.

So what I'm not understanding is where is the danger here?

 

[timselectric]

Ok let me understand -

Euro inverter is sending power to a usa 240v load via L,N

Euro inverter has neutral bond to ground.

Under normal operation ground carries no current since the power is flowing from l1, through the load, and back to the inverter via neutral.

Let's say load is a USA 240v water heater and everything is working as normal.

Now, if L1 from the euro inverter somehow touches the metal case of the USA water heater, the 240v from the inverter will flow through the grounded metal case of the water heater, via the ground wire, to ground ,BUT since ground and neutral are bonded at the inverter, it will ultimately complete it's normal course of flowing back to it's source.

So what I'm not understanding is where is the danger here?

In North American equipment the L1 and L2 are isolated from ground. For a simple element water heater, it probably wouldn't matter. For most other equipment (with electronics or control circuits) it would be a problem.
Like a dryer, or range.
The older ones have a 3 wire cord. The newer ones have a 4 wire cord. But all require a split-phase ground. (120v from L1 or L2 to ground)