2 strings, different panels

[LaChab]

Good Morning,

I've had approval for 18 panels.

Purely for convenience, I bought 9 panels last week. https://www.cityplumbing.co.uk/p/longi-solar-hi-mo-6-430wp-full-black-pv-module-lr5-54htb-430m/p/836339

Now they've been delivered I went to order the other 9, only to find that CP no longer have any stock!

The only ones available are these, which have slightly different specs, but look the same. https://www.cityplumbing.co.uk/p/longi-solar-435wp-full-black-pv-module-lr5-54htb-435m/p/104462

As they'll be on 2 strings, am I ok to  use two different panels?

 

Thanks for reading,

[MikeGrahamT21]

I can't say for sure 100%, as i've never heard of anyone doing this, but from a technical perspective the inverter doesn't know what type of panels they are, so having the 2 types on differing strings I would say is absolutely fine and shouldn't pose any issues.

 

Speak to your inverter manufacturer if you want a 100% sure answer

[LaChab]

@MikeGrahamT21Thanks for the thoughts.

[Susie]

Have you tried using 

https://easy-pv.co.uk/

the free account is ok and you can select different panels on different strings. 

[LaChab]

@Susie That looks very interesting! Thanks, I'll have a (free!) go. PS been enjoying your blog, and the Part O spreadsheet satisfied the BCO.

[Mattg4321]

Don’t see why not if on different MPPT’s

[LaChab]

@Mattg4321 THanks,  I'm tempted to give it a go!

[frankmcs65]

Hi ,it's by all means possible,I've done it It's better,though if they match somehow in voltage and watts....Mine (9) Lg neon black bifacial to east and(6) Axitec bifacial 540-700W towards south work,even there's a slight voltage mismatch between the two strings I've chosen east south because I've got hills on the east,which leaves me without sun in the afternoon ....Best regards Frank

[Dillsue]

23 hours ago, LaChab said:

Good Morning,

I've had approval for 18 panels.

Purely for convenience, I bought 9 panels last week. https://www.cityplumbing.co.uk/p/longi-solar-hi-mo-6-430wp-full-black-pv-module-lr5-54htb-430m/p/836339

Now they've been delivered I went to order the other 9, only to find that CP no longer have any stock!

The only ones available are these, which have slightly different specs, but look the same. https://www.cityplumbing.co.uk/p/longi-solar-435wp-full-black-pv-module-lr5-54htb-435m/p/104462

As they'll be on 2 strings, am I ok to  use two different panels?

 

Thanks for reading,

They look to be the same panel with 5 watt difference? If that's the case you'll be fine mixing and matching. You can put them on separate MPPT inputs on your inverter if you want to get the last 36watts(5x9) out of them, but you're unlikely to notice the 36w loss if you mix them up

 

For clarity your official approval is almost certainly for your inverter output not the number or capacity of panels connected to it, so don't get hung up on the number of panels you have if other panel configurations would work better for you.

Edited December 7 by Dillsue

[LaChab]

@frankmcs65, @Dillsue Thanks for the encouragement, I'll get on and order them. When the electric supply eventually gets restored!