Three string Inverter

robh71

Hi,

Planning to replace existing system (south facing) with higher spec panels across south, east & west facing. Have been told that in doing so involves using 3 strings into inverter which is counter-productive and I should only use 2 string, i.e. south and west facing. Is using three different facing roofs an issue and if so are there inverters which can accommodate the issue this presents?

Regards

DC999

'Is using three different facing roofs an issue' - no, I have that. But on 2 inverters.

Most inverters have 2 strings, some have 1. 3 would be uncommon afaik. If the existing one is 2 string, keep that for 2 orientations (once it can handle the no. of panels). Then get a 1 string one for South. Or get a 2 string one and have a spare if needed for room to expand in the future.

I've 2 inverters for that reason as have 3 orientations. There is some device in one inverter to pair the 2nd as a 'slave' so I can see the stats for both. So that works on Huawei at least. I'd assume if you get the same brand, there is a way to see the stats for both.

Gets more complex if you have a battery though with 2 inverters, I don't have one.

Or can sell the existing inverter, there's a thread here. There is deffo a 2nd hand market. Then you could get the inverter(s) you need.

robh71

Thanks DC999, I'll ask the company of they can support 2 inverters. In relation to 2nd hand market where is best place to advertise what I'm replacing, i.e. 6 x 265w Conergy + Sunny Boy Inverter (SB1.5-1VL-40 650) and what would be approx. fair price?

DC999

Plonk on the sale thread here on this forum. And people then post on Adverts.ie too. See a previous ones here to get a sense of prices

idc

Optimisers are another option for multiple orientations but every panel on the string must have an optimiser

10-10-20

https://www.boards.ie/discussion/comment/120663020#Comment_120663020

That's not correct. Tigo's optimisers can be installed selectively, some others require all panels connected. See this link:

https://midsummer.ie/buy/tigo-optimisers

robh71

https://www.boards.ie/discussion/comment/120662818#Comment_120662818

Thanks. Apologies but I cant se that sale post. Is it a post in this Renewable Energies forum?

con747

https://www.boards.ie/discussion/comment/120663194#Comment_120663194

https://www.boards.ie/discussion/2058260098/renewable-stuff-for-sale-and-wanted#latest

robh71

Ah great thank you

idc

https://www.boards.ie/discussion/comment/120663077#Comment_120663077

What I said is correct in terms of two similar sized strings. Selective optimisers only works when you have few panels on another orientation. if you had 12 panels split 6+6 over two orientations then you would need to have optimisers on all panels.

Better info here for anyone considering doing this

Designing your TS4 system for different tilts, angles, and orientation – Tigo Help Center (tigoenergy.com)

SD_DRACULA

Look into the sunsynk 8kw, It has 4 inputs, split across 2 mppts and you might get away with it as it just parallels the 2 inputs per mppt.

@unkel that sounds about right for what he needs?

10-10-20

https://www.boards.ie/discussion/comment/120664920#Comment_120664920

Thank you. I misunderstood the application of the Tigo units.