Question on my UPS

[woodgeek]

Your arrangement makes sense. I think one diode per panel will be useful if you have any shading issues at all, but cost you a few % output if you don't. Of course, it wouldn't help with a panel going open circuit, but it sounds like you have that under control.

One thing not mentioned....a fuse near the battery, or ideally in its box. I have a little 'micro' system I set up, 20W panel and 40 Ah battery. I put a 30A automotive fuse in the box for safety. While it is low voltage, a big battery can certainly start a fire through a short.

 

[Jags]

Good to hear that you got them soldered back up.

And No, I don't believe a 15W panel and an 11W panel in parallel will reduce your output from the 15W.

Edit: I am not a solar junkie, so maybe there is something that I am unaware playing into this. I simply know zoomies.

 

[olddawgsrule]

You may want to consider posting on another forum such as http://www.solarpaneltalk.com/ as there are folks there who really do this sort of thing day in and day out (much like folks here know their wood and stoves).

I need to thank you once again for the suggestion.
The site is as good as this one.
Fast response from knowledgeable folks!
I will also recommend the site if we can not find a solution here.

 

[olddawgsrule]

Your arrangement makes sense. I think one diode per panel will be useful if you have any shading issues at all, but cost you a few % output if you don't. Of course, it wouldn't help with a panel going open circuit, but it sounds like you have that under control.

One thing not mentioned....a fuse near the battery, or ideally in its box. I have a little 'micro' system I set up, 20W panel and 40 Ah battery. I put a 30A automotive fuse in the box for safety. While it is low voltage, a big battery can certainly start a fire through a short.

You have the fuse setup between the charge controller and the battery?
Or between the panels and the charge controller?

I'm setting up a control circuit (like I don't have enough projects) and believe this could be a good addition.

 

[olddawgsrule]

Good to hear that you got them soldered back up.

And No, I don't believe a 15W panel and an 11W panel in parallel will reduce your output from the 15W.

Edit: I am not a solar junkie, so maybe there is something that I am unaware playing into this. I simply know zoomies.

I popped over to the site Slow1 recommended and they confirmed my understanding.
It will reduce production, but it looks like not all the way to the 11 watts.
I'm still trying to fully understand it myself...

Mis-match of watts or voltage leads towards the smaller of the watts/voltage.

If I have it right (which I'm still working on/learning), I would need to setup a second array/charge control to add these 11 watt panels and gain what they produce in addition to what I have already.

Seems like quite a pain in the butt...
I know, go out and buy a 200 watt panel and get it over with....
If only I could find the deal locally (no shipping involved)...

 

[Jags]

It will reduce production, but it looks like not all the way to the 11 watts.

Cool, so it acts like two resistors of different sizes in parallel. Your final resistance will neither be as high as the big one, but won't be as low as the small one.

 

[woodgeek]

Your arrangement makes sense. I think one diode per panel will be useful if you have any shading issues at all, but cost you a few % output if you don't. Of course, it wouldn't help with a panel going open circuit, but it sounds like you have that under control.

One thing not mentioned....a fuse near the battery, or ideally in its box. I have a little 'micro' system I set up, 20W panel and 40 Ah battery. I put a 30A automotive fuse in the box for safety. While it is low voltage, a big battery can certainly start a fire through a short.

You have the fuse setup between the charge controller and the battery?
Or between the panels and the charge controller?

I'm setting up a control circuit (like I don't have enough projects) and believe this could be a good addition.

I have a fuse at the battery, nearest the + terminal, such that if I shorted anything outside the battery box, either on the line to the controller or the line to my inverter, it would pop the fuse, rather than surge through the wire and start a fire. Shorting the panels is not really a hazard (esp for these small panels).