What portable solar panels are safe to wire in series when shaded?

[Jman99]

I have a foldup glass and alloy panel that consists of 3 individual 36cell panels, I want to wire them all in series so I can place the panel far away & use small cables.
I have read if there are not enough bypass diodes and one panel is shaded it can damage it or at the very least degrade overtime. Here is what it looks like in the black box on each panel.


Is this enough to safely wire them in series? I use these alot in places that see shade. Also what about the new compact ETFE types with up to 5 individual panels?

thanks

 

[john61ct]

No safety issue or degradation.

Big voltage currents are of course inherently more dangerous.

But the reason to avoid series connected panels is that any partial shading reduces the overall production disproportionally.

On 50Voc panel with a good MPPT SC will out perform the same wattage produced by 2x 25Voc panels in series.

You just won't likely find the former at Home Depot, more from the professional supply channels sold by the pallet load, so takes some digging, ideally locally.

 

[Alloy]

Does the panel manufacture provide a maximum system voltage?

My $0.0002 from the site we visit is the convenience of smaller wire will be traded off moving series run panels out of the shade. My "portable panel" are 5.7A@70V in parellet with 8ga (50' sections). The 8ga was used to minimize system loss on the worst days.

 

[Jman99]

No safety issue or degradation.

Big voltage currents are of course inherently more dangerous.

But the reason to avoid series connected panels is that any partial shading reduces the overall production disproportionally.

On 50Voc panel with a good MPPT SC will out perform the same wattage produced by 2x 25Voc panels in series.

You just won't likely find the former at Home Depot, more from the professional supply channels sold by the pallet load, so takes some digging, ideally locally.

ta, I will be plugging and unplugging via anderson plugs, could the arc of high voltage of say 60-80V be a problem?

Does the panel manufacture provide a maximum system voltage?

My $0.0002 from the site we visit is the convenience of smaller wire will be traded off moving series run panels out of the shade. My "portable panel" are 5.7A@70V in parellet with 8ga (50' sections). The 8ga was used to minimize system loss on the worst days.

Not sure what you mean by max system voltage? Each cell is just the standrad 21Voc type. The whole fold panel are all parallel.

From my experince out in bush I would say shade both series & parallel are close, even in parallel they are prone to getting shaded and one single panel can be knocked out easily. Plus in series each panel have the bypass diodes the rest of panels can carry on.

 

[john61ct]

ta, I will be plugging and unplugging via anderson plugs, could the arc of high voltage of say 60-80V be a problem?

No, but best to get hooked up, last thing you do is unfold or uncover.

SCs connected to battery first and disconnected last of course, reverse order for everything

 

[Alloy]

ta, I will be plugging and unplugging via anderson plugs, could the arc of high voltage of say 60-80V be a problem?




Not sure what you mean by max system voltage? Each cell is just the standrad 21Voc type. The whole fold panel are all parallel.

From my experince out in bush I would say shade both series & parallel are close, even in parallel they are prone to getting shaded and one single panel can be knocked out easily. Plus in series each panel have the bypass diodes the rest of panels can carry on.

Max system voltage is the highest voltage a manufacturer rates the panels for.

Are you using a PWM or MPPT controller? MPPT will accept a higher voltage.

Once there is shading the output of parellel exceeds series.

 

[Alloy]

I say no problem. Andersons can be hotplugged several hundred times at full load. Which I seriously doubt this array will come close to outputting.
But we dont your solar array wattage...
Said that, I cant imagine its over 200W if even that. Anything over would become crazy awkward to use as a portable.

A H2000 generator is 50lbs.
A 330w panel is 42lb.
A 14yo can carry either one.