Mix & match PV panels OK? Installers Surrey?

Snuggy
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Mix & match PV panels OK? Installers Surrey?

#1

Post by Snuggy »

Hi, I see some members have different brand or wattage panels installed, do these need to be on different strings?

Secondly can anyone offer good or bad feedback on installers in Surrey (Guildford Camberley Woking area)
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Joeboy
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Re: Mix & match PV panels OK? Installers Surrey?

#2

Post by Joeboy »

Hi Snuggy,
Welcome to the forum. You can mix and match panels but there will be losses if the imbalance is great as the string power (Amps) will default to the lowest outputting panel in the string.

If you can keep your panel voltages and Amps as close as you can in each string.

What are your plans for the system?
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dan_b
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Re: Mix & match PV panels OK? Installers Surrey?

#3

Post by dan_b »

Welcome!

Look up So Go Solar - they installed my home array and our work system - Ben is a top bloke very thorough.
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Countrypaul
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Re: Mix & match PV panels OK? Installers Surrey?

#4

Post by Countrypaul »

Joeboy wrote: Wed Jun 19, 2024 2:33 pm Hi Snuggy,
Welcome to the forum. You can mix and match panels but there will be losses if the imbalance is great as the string voltage will default to the lowest outputting panel in the string.

If you can keep your panel voltages as close as you can in each string.

What are your plans for the system?
Joe are you sure you mean voltage? If you have a string with several panels in series surely the voltage will be the sum of the individual panels, but the current might be limited by the smallest?
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Joeboy
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Re: Mix & match PV panels OK? Installers Surrey?

#5

Post by Joeboy »

Countrypaul wrote: Wed Jun 19, 2024 2:48 pm
Joeboy wrote: Wed Jun 19, 2024 2:33 pm Hi Snuggy,
Welcome to the forum. You can mix and match panels but there will be losses if the imbalance is great as the string voltage will default to the lowest outputting panel in the string.

If you can keep your panel voltages as close as you can in each string.

What are your plans for the system?
Joe are you sure you mean voltage? If you have a string with several panels in series surely the voltage will be the sum of the individual panels, but the current might be limited by the smallest?

Edit- you are right Paul.The voltages in series are added together. If a lower Amp panel was in the string, it would be the default current output for the string I'm away to edit, cheers!

I found the link below, it's quite 👍

https://solarpanelsvenue.com/mixing-solar-panels/
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Countrypaul
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Re: Mix & match PV panels OK? Installers Surrey?

#6

Post by Countrypaul »

Joeboy wrote: Wed Jun 19, 2024 2:53 pm
Countrypaul wrote: Wed Jun 19, 2024 2:48 pm
Joeboy wrote: Wed Jun 19, 2024 2:33 pm Hi Snuggy,
Welcome to the forum. You can mix and match panels but there will be losses if the imbalance is great as the string voltage will default to the lowest outputting panel in the string.

If you can keep your panel voltages as close as you can in each string.

What are your plans for the system?
Joe are you sure you mean voltage? If you have a string with several panels in series surely the voltage will be the sum of the individual panels, but the current might be limited by the smallest?
I'm pretty sure the voltage defaults to the lowest but always wondered at the mechanism. Happy to be shown the error of my ways though!

Edit- you are right Paul.The voltages in series are added together. If a lower Amp panel was in the string, it would be the default. I'm away to edit, cheers!

https://solarpanelsvenue.com/mixing-solar-panels/
Found this site which appears to explain mixing panels: https://solarpanelsvenue.com/mixing-solar-panels/
Note that this is just the first site I found.
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Joeboy
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Re: Mix & match PV panels OK? Installers Surrey?

#7

Post by Joeboy »

Countrypaul wrote: Wed Jun 19, 2024 3:03 pm
Joeboy wrote: Wed Jun 19, 2024 2:53 pm
Countrypaul wrote: Wed Jun 19, 2024 2:48 pm

Joe are you sure you mean voltage? If you have a string with several panels in series surely the voltage will be the sum of the individual panels, but the current might be limited by the smallest?
I'm pretty sure the voltage defaults to the lowest but always wondered at the mechanism. Happy to be shown the error of my ways though!

Edit- you are right Paul.The voltages in series are added together. If a lower Amp panel was in the string, it would be the default. I'm away to edit, cheers!

https://solarpanelsvenue.com/mixing-solar-panels/
Found this site which appears to explain mixing panels: https://solarpanelsvenue.com/mixing-solar-panels/
Note that this is just the first site I found.
Aye, the same site? :facepalm: :D

At least we're consistent!
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nowty
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Re: Mix & match PV panels OK? Installers Surrey?

#8

Post by nowty »

It can be a complicated business and unless you know what you are doing, stick to the same panels all pointing in the same direction and elevation angle for each string. If you can get the strings nearly identical you can parallel them up into the same inverter / charge controller MPPT input even with differing direction and elevations.

You can also use TIGO's (voltage optimisers) to help uneven strings but thats another science in itself.

Question (or puzzle) for you all,

How many strings can you see in this picture and I am not using any TIGOs. ?

Image
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Snuggy
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Re: Mix & match PV panels OK? Installers Surrey?

#9

Post by Snuggy »

I think I mean watts? But hey I was pants at physics so you guys lost me in the discussion above!!

Say for example could I have a row of large panels for example
JA Solar 565W (JAM72S-30-565-LR) and underneath another row of JA Solar 425W (JAM54S-30-425-LR-BF) This is simpler than what I am proposing but I want to know if they will work ok, or if I am better to keep to the same wattage panel and not maximise my roof space.

I am hoping to understand your next answer Thanks
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Fintray
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Re: Mix & match PV panels OK? Installers Surrey?

#10

Post by Fintray »

nowty wrote: Wed Jun 19, 2024 3:31 pm Question (or puzzle) for you all,
How many strings can you see in this picture and I am not using any TIGOs. ?
5 maybe 6? :xx:
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