Strings: 1 x 12 or 2 x 6?

[smag]

Quick question....Have install with very slight shading early and late in the winter/autumn only.
3000TL with the 2 x MPPT split 2 x 6 or 3000TL/HF with 1 x 12 string?

Question really is does 2 strings x 6 modules compare with one long 1 string x 12 modules? Yield v similar on Sunny Design but always thought it was best to maximise the string (within the limits of the inverter obviously).

Thanks

 

[Worcester]

Both inveters only have a single MPP tracker. So unless both strings are equally shaded one will always affect the other, similarly if one string then all will also be affected.

When a panel is shaded, its voltage will drop, so you'll need to see what the parameters are for each inverter so that it doesn't drop too low.

So the question is what is the layout of the panels, which ones are affected, and how.

 

[smag]

Thanks for the response. Just had a DOH! moment. Was confusing it with the 4000TL. Shading not a major issue really. Modelled it on Google Sketchup and the shading really is minimal and only in low light conditions when it is. Not enough to consider using an inverter with 2 MPPT's.
What is you opinion on the 2 x 6 or 1 x 12 being best for my own sanity as there are 2 inputs on the one MPPT tracker for the 3000TL?? Checked the datasheet this time!

 

[Worcester]

In which case it's about ensuring that the Volatge coming out of the panels stays within the optimal range of the inverter, small # of panels, lower voltage, shading and heat will lower it further, - make sure not too low. Large # of panels may be near the upper limit of the optimal range. ( The 3000TL has both its upper and lower Voltage parameters higher than the 3000HF)

Assuming that either configuration falls within the parameters, it would be easy enough to trial and monitor both solutions anyway - get it wired as two strings and then you can join one string to the other at the inverter end so that they are in series instead of parallel (makes sure to isolate the inverter from the AC and make sure you get 2 DC isolators and turn them off first, that way you'll be working with dead cables, otherwise you'll get a big spark!).

Both the SMA series HF and TL inverters come with bluetooth, so you can get yourself Sunny Explorer for free and monitor it to your heart's content

 

[pirhead]

Can I ask what MPPT means-sorry if it is obvious

 

[pirhead]

Can I ask what MPPT means-sorry if it is obvious:6:

 

[smag]

Thanks Worcester.
Pirhead. Maximum power point tracker. It is the part of the inverter which measures the voltage and current and optimises them so the maximum power is output (power being a finction of the 2).

 

[pirhead]

Ah Thank you smag:stooge_curly: