DIY Solar install

[lord-of-war]

Hi Roux, have you progressed with this project?

 

[leon.davibe]

Better to run them in parallel if only 1 panel is enough to start the solar controller.

Not allways the case what i have found installing panels as i have cash meaning the voltage was at a stage very close to startup voltage

Lifting the voltage by just one extra panel made a massive difference to the production

ie on the hot days the voltage vmp/voc drops and to stay in the mppt range panel has to produce power at a higher voltage sometimes dragging it into voc voltage where output be almost nothing

So you definitely don't want to be too close to startup voltage

 

[wingnut771]

Not allways the case what i have found installing panels as i have cash meaning the voltage was at a stage very close to startup voltage

Lifting the voltage by just one extra panel made a massive difference to the production

ie on the hot days the voltage vmp/voc drops and to stay in the mppt range panel has to produce power at a higher voltage sometimes dragging it into voc voltage where output be almost nothing

So you definitely don't want to be too close to startup voltage

Iirc there is shading.

 

[leon.davibe]

Iirc the panels in question are 150W.

Yea on 12/24v systems with a high cell count panel you won't bump into this

But yea if you have lower cell count panels the same pitfall applies

You want your vmp to be at least 20-25% above startup voltage imo

 

[wingnut771]

Yea on 12/24v systems with a high cell count panel you won't bump into this

But yea if you have lower cell count panels the same pitfall applies

You want your vmp to be at least 20-25% above startup voltage imo

Sorry I edited my post. Have you read the thread?

 

[leon.davibe]

Iirc there is shading.

Then Even Worse
Then you want enough panels in series that after shading reduces them that you have a voltage still higher than bottom of mppt range

 

[wingnut771]

Then Even Worse
Then you want enough panels in series that after shading reduces them that you have a voltage still higher than bottom of mppt range

Have you read the thread? Why are you responding to posts from 6 months ago?

 

[leon.davibe]

Have you read the thread?

Not recently a while back and know that roux did up his panels count and changed inverter too if i remember correctly, different thread

New post got me onto the thread again

Since i got my panels up , one panel at a time, the increase in production with each addition wasn't linear on the bottom of the voltage range , once a decent amount over mppt bottom then it was linear

and just thought to mention that just,just making it into mppt range isn't ideal

 

[wingnut771]

Not recently a while back and know that roux did up his panels count and changed inverter too if i remember correctly, different thread

New post got me onto the thread again

Since i got my panels up , one panel at a time, the increase in production with each addition wasn't linear on the bottom of the voltage range , once a decent amount over mppt bottom then it was linear

and just thought to mention that just,just making it into mppt range isn't ideal

so you remember it was a 500W panel on a 1000W inverter then so has more than enough startup voltage?

 

[leon.davibe]

so you remember it was a 500W panel on a 1000W inverter then so has more than enough startup voltage?

Yes
For a 12v/24v system it would take some effort/shading to get it wrong as most big panels exceed the startup voltage by a decent margin

 

[wingnut771]

Yes
For a 12v/24v system it would take some effort/shading to get it wrong as most big panels exceed the startup voltage by a decent margin

Please read the thread again as you are reading my parallel advice out of context or something.

 

[Rouxenator]

Hi Roux, have you progressed with this project?

The saga continued here.