What's the reason behind using 240V inverters with transformers when they have split phase ones?

[John Frum]

Post 55

"For those that are looking for a system to actually run something? Duh!

This is about comparing the capacity of various split phase inverter setups. We don't care about your puny system."

Post 68

"If the neutral goes open, you will feed 240V out on the 120V circuits; I guess some people like new appliances........"

Even after I tried to re claify I was talking again about 240V system and that I had come to the conclusion that a isolation transformer was the way to go ,even if I got a model number wrong, he choose to be who he is. If you want to make a point you generally don't throw a insult in at the end as it negates everything you said in the beginning.

Yep, I missed it.

I think you are referring to...
"Duh!" which is an insult to your intelligence.
"puny system" which is an insult to your system.
"I guess some people like new appliances........" some kind of insult maybe.

Thanks for taking the time.

 

[timselectric]

If you buy the Signature Solar version of the SPF5000ES (US) inverter, it has been modified by the factory to not have the L2 / Ground bond. This has been well documented here.

If you buy a random one from China or eBay, all bets are off. More than likely you will get one that has a relay that connects ground to L2 depending on the mode of the inverter.

This is also true for the ones sold on Amazon.
Don't ask me how I found this out. lol

 

[realpinochet]

If you buy the Signature Solar version of the SPF5000ES (US) inverter, it has been modified by the factory to not have the L2 / Ground bond. This has been well documented here.

If you buy a random one from China or eBay, all bets are off. More than likely you will get one that has a relay that connects ground to L2 depending on the mode of the inverter.

Ah ok. I was hoping that L2 ground was selectable.

From what I've seen the cheaper ones like mpp / growatt seem to use a screw that often is removable internally. But, I'd highly suggest checking with the manufacturer before buying one of these to make sure you can do this. Signature solar seems to order ones with the screw removed at the factory as opposed to you removing it yourself.

 

[realpinochet]

Yep, I missed it.

I think you are referring to...
"Duh!" which is an insult to your intelligence.
"puny system" which is an insult to your system.
"I guess some people like new appliances........" some kind of insult maybe.

Thanks for taking the time.

That's for this thread like you asked...but he's the same way with others throughout this forum when people disagree with him. I'm new to this forum and I realized this before even posting my first post about this particular person. We can act like adults and converse as such ..even when people disagree with us or fail to get our points across.

 

[timselectric]

Actually the ones from SS don't even have the trace on the board.

 

[realpinochet]

Actually the ones from SS don't even have the trace on the board.

Thanks Tim...good to know. So, it is indeed a specific model for them.

 

[timselectric]

Thanks Tim...good to know. So, it is indeed a specific model for them.

Yes
Special made
For SS, in the US. And another company in Canada. (Can't remember their name, at the moment)

 

[Vigo]

Ah ok. I was hoping that L2 ground was selectable.

Anything is selectable if you make it selectable. That's what i did. But it's simpler to buy the 'correct' version if it's available and you're not confident modifying a brand new ~$1k pile of circuit boards. Or two, in my case.

I have two 'small' (i.e. if i say what they are, guaranteed someone will say they are undersize and i am about to die) transformers and i have seen their idle consumption to be roughly 7 watts or so.

 

[realpinochet]

There's another user that uses this 50 Kva transformer for isolation and he's getting good results with his growatt setup. He's a electrician and lineman by trade.

HAMMOND SG3N0050LE D16 SNTL-G3 1PH 50KVA 240X480-120/240V AL 60HZ 150C 3R | Gordon Electric Supply, Inc.

HAMMOND SG3N0050LE D16 SNTL-G3 1PH 50KVA 240X480-120/240V AL 60HZ 150C 3R

www.gordonelectricsupply.com

I found this 25 Kva one that seems to be the same but just smaller.

SQUARE D EE25S3H : XFMR DRY 1PH 25KVA 240X480V-120/240V | Gordon Electric Supply, Inc.

SQUARE D EE25S3H : XFMR DRY 1PH 25KVA 240X480V-120/240V

www.gordonelectricsupply.com

 

[Jack Rabbit Off Grid]

If you want split phase don’t bother buying a Magnum. Their customer service sucks! Been on the phone all morning calling every phone number I can google. Finally a woman answered the phone and is was a security officer. She finally got me to another woman. I told her my story and asked if magnum was even still in business. She didn’t know but said she will look into it and get back to me. We will see.

 

[realpinochet]

If you want split phase don’t bother buying a Magnum. Their customer service sucks! Been on the phone all morning calling every phone number I can google. Finally a woman answered the phone and is was a security officer. She finally got me to another woman. I told her my story and asked if magnum was even still in business. She didn’t know but said she will look into it and get back to me. We will see.

Something is going on with them, they can't get any stock for a long time now.

 

[Jack Rabbit Off Grid]

Something is going on with them, they can't get any stock for a long time now.

I was told two rumors by two different vendors of Magnum products. One they were in the middle of moving off shore. Two they were moving to Mexico. But regardless answer a phone or return an email. Don’t just let your customer base hanging.

 

[Zwy]

I've seen your comments / interactions on this forums with others and there's a pattern..you're compelled to be insulting and condescending when there's no reason to act that way. Please move past any future post of mine!

Just trying to be helpful to others and hopefully they move in the right direction. I see so many mistakes made, many misconceptions, I have to wonder how many unsafe systems are out there.

This gives a bad name to DIY solar projects. The end result will be heavy regulation or outright bans on DIY solar projects.

 

[HowlerMonkey]

Transformers are certainly more hardy than semiconductors.

 

[Texican]

Oh I'd love see links to these products. I could use some more PV at 18cent. And only 40Kw inverters that google gives me are industrial $15k ones.

I bought 2 pallets of used 250w panels from Signature Solar for .20 watt, 7 months ago. they are working great

 

[HowlerMonkey]

If I am the only house on my utility power pole transformer, would that mean an isolation transformer in my system would not try to “balance my neighbors’ power” mains feed?

 

[Shimmy]

If I am the only house on my utility power pole transformer, would that mean an isolation transformer in my system would not try to “balance my neighbors’ power” mains feed?

No such thing. An isolation transformer just isolates your neutral from your neighbors, and along with that the ground.

Deriving a ground close to the neutral-ground bond at your house has some advantages, especially with induced lightning currents.

 

[timselectric]

If I am the only house on my utility power pole transformer, would that mean an isolation transformer in my system would not try to “balance my neighbors’ power” mains feed?

An isolation transformer "isolates" the newly formed system from the original system that powers it.
The issue with (possibly) balancing the neighborhood loads, is from using an autotransformer in parallel with the grid.

 

[HowlerMonkey]

I know some say there is no current used by an isolation transformer’s primary windings when no loads are on the secondary but that seems impossible.

 

[rpdom]

I know some say there is no current used by an isolation transformer’s primary windings when no loads are on the secondary but that seems impossible.

A transformer without any load on the secondary is basically an inductor and as such will block AC current. It's not quite as simple as that in reality though.