Does the amount of cells in a panel matter?

[Wrath of Khan]

Just a quick question:

Does the amount of cells in a solar panel matter to your inverter?
Reason being my inverter says, "adapted to 60 & 72 cell PV panels"
The operating voltage range is 16-60v

The panel I am looking at is 380w / Voc 42v / 120 cells...

 

[Speedster]

Just a quick question:

Does the amount of cells in a solar panel matter to your inverter?
Reason being my inverter says, "adapted to 60 & 72 cell PV panels"
The operating voltage range is 16-60v

The panel I am looking at is 380w / Voc 42v / 120 cells...

120 cells are actually 60 half cells. Number of cells doesn't really matter for any practical purposes, as long as your string voltage is within the mppt spec.

 

[Wrath of Khan]

120 cells are actually 60 half cells. Number of cells doesn't really matter for any practical purposes, as long as your string voltage is within the mppt spec.

perfect thanks I shall order the panels tomorrow!

 

[itareanlnotani]

Panel Voltage will be higher with more cells.

You must have a pretty low end inverter if thats one of the sales points.

Which inverter is it? Or is it just a pwm or mppt unit?

 

[Wrath of Khan]

Panel Voltage will be higher with more cells.

You must have a pretty low end inverter if thats one of the sales points.

Which inverter is it? Or is it just a pwm or mppt unit?

its a micro inverter, so will attach 4x 380w panels to the inverter

 

[itareanlnotani]

its a micro inverter, so will attach 4x 380w panels to the inverter

At, that makes sense then, as its a micro inverter. You need to be very careful speccing out the panels for this.
Lower watt panels only really, as they haven't kept up with the times.


60v/10.5A max. Check VOC carefully for your panels, and add 10% or 15% on top of VOC as that can be exceeded.

Amps can generally be clipped, but voltage going over means magic smoke go boom boom, and device unhappy chappy.

So. Be. Careful.

 

[Corelli]

Its about efficiency and not the amount of cells

 

[itareanlnotani]

Its about efficiency and not the amount of cells

In his case, it's about the micro inverter is only usable for older lower rated panels, so different concerns.

 

[Wrath of Khan]

At, that makes sense then, as its a micro inverter. You need to be very careful speccing out the panels for this.
Lower watt panels only really, as they haven't kept up with the times.


60v/10.5A max. Check VOC carefully for your panels, and add 10% or 15% on top of VOC as that can be exceeded.

Amps can generally be clipped, but voltage going over means magic smoke go boom boom, and device unhappy chappy.

So. Be. Careful.

I wish they would be more specific in their paperwork on these inverters.
Ok so this inverter says it can take 4x 380w panels

The panel Voc = 41.6v
Short circuit amps = 11.47a
Max power amps = 10.93a

Inverter max operating voltage 16-60v (I'm guessing that's the Voc)
Maximum Input Current = 10.5a (but amps aren't critical as I believe they get clipped or something)

What they don't say in the paperwork is that I'm sure that's per connection right?! (which their are 4 --> for the 4 panels) If I take 41.6v out of a max 60v allowed, then I'm only at 69%, so should be perfect

So all the above will be per panel, and I attach 4 panels to the inverter. I guess the inverter connections are obviously in parallel and not series otherwise the voltage would pop it.

 

[itareanlnotani]

I wish they would be more specific in their paperwork on these inverters.
Ok so this inverter says it can take 4x 380w panels

The panel Voc = 41.6v
Short circuit amps = 11.47a
Max power amps = 10.93a

Inverter max operating voltage 16-60v (I'm guessing that's the Voc)
Maximum Input Current = 10.5a (but amps aren't critical as I believe they get clipped or something)

What they don't say in the paperwork is that I'm sure that's per connection right?! (which their are 4 --> for the 4 panels) If I take 41.6v out of a max 60v allowed, then I'm only at 69%, so should be perfect

So all the above will be per panel, and I attach 4 panels to the inverter. I guess the inverter connections are obviously in parallel and not series otherwise the voltage would pop it.

Looking at the unit, it has 4 paired connectors, so would likely be in the center of your 4 panel mounting.
Each connector directly to a panel, so no parallel or serial setup on the panels themselves.








Any particular reason you're going with a micro inverter?

You just want AC supplemented?
This won't help with load shedding, only with supplementing existing grid - i.e. to reduce your bill.



Their website says that the MI-1200 can do 11.5A max @ 60V

Microinverter-single-phase -FR - Hoymiles

Micro-onduleurs monophasés Les micro-onduleurs convertissent l’énergie captée par vos panneaux solaires en électricité utilisable. Les micro-onduleurs monophasés sont généralement utilisés dans les environnements résidentiels et les petits commerces. Hoymiles, c’est la garantie de performances...

www.hoymiles.com

Datasheet - https://www.hoymiles.com/wp-content/uploads/2022/06/User-Manual_HME-12001500-AU_V202203.pdf

 

[Wrath of Khan]

Looking at the unit, it has 4 paired connectors, so would likely be in the center of your 4 panel mounting.
Each connector directly to a panel, so no parallel or serial setup on the panels themselves.

View attachment 1346584

View attachment 1346612




Any particular reason you're going with a micro inverter?

You just want AC supplemented?
This won't help with load shedding, only with supplementing existing grid - i.e. to reduce your bill.



Their website says that the MI-1200 can do 11.5A max @ 60V

Microinverter-single-phase -FR - Hoymiles

Micro-onduleurs monophasés Les micro-onduleurs convertissent l’énergie captée par vos panneaux solaires en électricité utilisable. Les micro-onduleurs monophasés sont généralement utilisés dans les environnements résidentiels et les petits commerces. Hoymiles, c’est la garantie de performances...

www.hoymiles.com

Datasheet - https://www.hoymiles.com/wp-content/uploads/2022/06/User-Manual_HME-12001500-AU_V202203.pdf

Ja I have a lot of shading on my roof from the neighbours tree... I was just about to get a "normal" hybrid inverter and then found out about the shading issue on 1 panel which would then affect them all. All the info I found was that on a micro-inverter system shading is not an issue as it only affects that particular panel. And the wiring for the AC side of things is straight forward, no DC at all

Oh and yeah not for load-shedding, it's just to reduce my electricity bill. I have big freezers that runs all the time so my elec is around R5k a month. If I can get solar during the day time then that should reduce my bill "hopefully"

I can't afford batteries etc, maybe one day I'll save up for a big battery cart that I can then plug directly into a DB board and then switchover at night when there's a power failure. But I'm ok for now

 

[wingnut771]

Ja I have a lot of shading on my roof from the neighbours tree... I was just about to get a "normal" hybrid inverter and then found out about the shading issue on 1 panel which would then affect them all. All the info I found was that on a micro-inverter system shading is not an issue as it only affects that particular panel. And the wiring for the AC side of things is straight forward, no DC at all

Oh and yeah not for load-shedding, it's just to reduce my electricity bill. I have big freezers that runs all the time so my elec is around R5k a month. If I can get solar during the day time then that should reduce my bill "hopefully"

I can't afford batteries etc, maybe one day I'll save up for a big battery cart that I can then plug directly into a DB board and then switchover at night when there's a power failure. But I'm ok for now

Do you have a spinning disk meter?

 

[Wrath of Khan]

Do you have a spinning disk meter?

yeah I've got both actually (because of 3 phase) I've got a spinning disk one and a digital one