Need new inverter for 10-year-old system... Where can I find a compatible one?

chrisp5683

Hi all,
I am a proud solar owner over the past 10 1/2 years, but my Sunpower SPR-3200 inverter recently decided that enough was enough and died on me. (Thank you Sunpower for that 10-year warranty!) :-(

Of course, this inverter (being as old as it is) is no longer manufactured. So my question is, what model(s) of inverter is suitable as a replacement for my SPR-3200? I have 16 Sunpower panels (I believe SPR-215's) that would be very happy to produce electricity once again.

PS you might say "contact a Sunpower master dealer and they'll hook you up"... Already did that, the one I called locally was negative helpful. Quoted me $4,000 initially, then brought the price down to "just" $2,800. Given that I have seen several Sunpower 3kW inverters online for under $1,000, I asked for an invoice... When they sent it, they didn't even have the decency to itemize it between parts and labor. My father-in-law is a salesman, and I can tell when I'm being taken advantage of. All I was to them was $$$$$$.

BB.

Assuming that you have 8 panel strings * 2 parallel strings, any GT inverter ~>2,700 Watt and 600 VDC or higher maximum input rating should be a good candidate.

https://www.solar-electric.com/sma-sunny-boy-sb3-0-us-grid-tie-inverter.html

I am not in the solar business, and details do matter...

-Bill

chrisp5683

Thanks so much BB for the information... By GT inverter, do you mean "galvanized"? I had heard that because my system is most likely positively grounded (unlike my children), many of the newer inverters (DL?) would not be usable.

I know just enough about this to be dangerous, so I appreciate the suggestion. I'll look into that Sunny Boy inverter right now.

BB.

GT is grid thief inverter. (Tied, not thief...)

There is a "newer" type of grid inverter that is not have galvanic isolation. Fancy name for an inverter that does not have a large transformer. By getting rid of the isolation transformer, they can save money on copper and weight.

I don't have an opinion on which is better or worse. They are probably similar overall.

Non- isolated grid inverters, I am not sure how they play with older generation SunPower panels (the early panels needed positive grounding or they could build up a charge in the solar cell that would reduce output by 20% or more).

Many isolated grid inverters these days have the option for + or - grounding.

- Bill

westbranch

Bill must have had too many Easter eggs today (Early!) he probably should have typed Grid Tied instead of
 Grid Thief 

Dave Angelini

I think he meant it! 40 cent a KWH and Tier fees for each of the 3 tiers.  I think he meant it!

BB.

Auto correct on my phone...

Oh well, at least somebody is reading my posts.

- Bill

Dave Angelini

Down in the valley they are charging 10% for each of the 3 tiers. Is this common Bill and how is the 10% calculated.
Just hearing this on the radio so I really just was curious. You are luck you do not need AC in summer. Alot of the folks down there are going to fry this summer with those rates. I think they start out at 85F in Fresno on many mornings......

BB.

Yep.... "Cheap" energy really makes life much easier and jobs more prevalent.

-Bill

Dave Angelini

Is auto correct on or is that an answer?

BB.

I think that is what I intended to type...

-Bill

a0128958

I wonder about the same thing.  My grid tied, batteryless system, with 36 panels divided into 3 strings, using a string inverter, was installed early 2010.  I'm using an SMA Sunny Boy 7000W inverter (SB7000US).

Fast forward 7+ years now.  The Sunny Boy inverter is now manufactured with a transformerless design.

And I believe the NEC has required 2 significant changes between then and now.  Arc-fault protection, and faster shutdown from the grid when it no longer has a voltage presence.  I believe the current Sunny Boy inverters have absorbed these design improvements into their current string inverter offerings.

So what's left?  Can you, or I, simply replace our eventually worn out existing string inverters, replace them with current offering, and we're done?.  Will they work just fine with panels of 8 years ago (mine are 225W/panel).  ?

Best regards,

Bill

BB.

I believe your panels require positive grounding. You will probably have to find transformer based GT Inverters to meet this requirement.

Call our host and see if they have further information.

http://solar-electric.com/

One of the "joys" of being your own energy supplier (GT or off grid). Time marches on and we are left trying to figure out how to hang on...

-Bill

a0128958

In my case, my Astronergy panels don't require positive grounding.  As confirmed by the fact that my SMA Sunny Boy transformer design 7000W inverter has a moveable fuse in the negative ground position.

Unless I'm missing something here I'll think I'll be able to replace my existing inverter with a new TL design SMA Sunny Boy, without any retrofit to the system effort required.

LMS_2020

chrisp5683 - I am assuming you must have installed a replacement inverter. I find myself in a similar predicament! Can you please share which inverter you ended up getting?