Not charging

[dvrdwn]

I have 2 100 watt solar panels wired in parallel wired into a Solarepiv 40a mppt charge controler. Its charging 2 12volt 100ah sealed lead acid batteries wired in parrallel. I'm getting less than 1 amp at peak sun. I think i should be seeing more. Can you help?

[booster]

How low is the battery state of charge? If they are full, you won't charge much at all. What battery type is the controller set to?

[markopolo]

Booster's two points:
1. batteries already charged
2. wrong profile selected

are excellent. I'll add that paralleled panels (assuming standard panels for 12V system) and an MPPT controller are not the best combo. An inexpensive PWM controller would do as well or nearly as well at a much reduced cost. MPPT controllers work best with higher input voltage. Is there a reason why the panels were installed in parallel and not in series?

[booster]

A quick look says that an external remote is needed for any settings, so that could make monitoring difficult for monitoring also if not used.


My first choice for MPPT is also series as long as partial shading isn't an issue.

[dvrdwn]

Can I wire the solar panels in series even though I have a 12 V system?


[
QUOTE=markopolo;82870]Booster's two points:
1. batteries already charged
2. wrong profile selected

are excellent. I'll add that paralleled panels (assuming standard panels for 12V system) and an MPPT controller are not the best combo. An inexpensive PWM controller would do as well or nearly as well at a much reduced cost. MPPT controllers work best with higher input voltage. Is there a reason why the panels were installed in parallel and not in series?[/QUOTE]

[markopolo]

Check the controller manual to be sure but a Google search for Solarepic 40a mppt charge controller turns up an MPPT controller rated for up to 150V DC input with automatic sensing a 12V or 24V battery.

[skagitstan]

Originally Posted by markopolo

Booster's two points:
1. batteries already charged
2. wrong profile selected

are excellent. I'll add that paralleled panels (assuming standard panels for 12V system) and an MPPT controller are not the best combo. An inexpensive PWM controller would do as well or nearly as well at a much reduced cost. MPPT controllers work best with higher input voltage. Is there a reason why the panels were installed in parallel and not in series?

My research, when I built Annie, AND my subsequent experience, is that MPPT works better than PWM in low light/ low sun angle situations. It scavenges available energy better, simply because it impedance matches panel and load better. At 12V, or at 24V.

Also, wiring in parallel helps minimize panel dropout due to partial shading. All conditions we deal with here in the PNW.

We've have no problem with running our 4 panels in parallel into our MPPT.


But I'll agree with the original suggestions to check charge and profile.

[markopolo]

I've always figure folks who buy MPPT controllers would wire the panels in series because of the advantages of using higher voltage input.


From: https://www.victronenergy.com/upload...WM-or-MPPT.pdf

Conclusion:
When using an MPPT charge controller there are two compelling reasons to
increase the PV voltage (by increasing the number of cells in series):
a) Harvest as much power as possible from the solar array, even at high cell temperature.
b) Decrease cable cross sectional area and therefore decrease cost.

[skagitstan]

Originally Posted by markopolo

I've always figure folks who buy MPPT controllers would wire the panels in series because of the advantages of using higher voltage input.


From: https://www.victronenergy.com/upload...WM-or-MPPT.pdf

I figured that the improvement in partial shade behavior of a parallel setup outweighed any high temperature losses, especially since we live (and mostly travel) in a cooler climate with lots of shade and sub-optimal panel orientation.


(I^2)R losses are handled by appropriate gauge cable. On a custom van build, with short runs (much shorter that you would expect in a fixed home array), they are not excessive.


If this was a fixed home setup, with a known clear location, I would certainly go for a higher voltage setup.

[dvrdwn]

My charge controller is disconnecting power to all loads when the batteries read bellow 13.5. I,m assuming it,s because the settings aren't set correctly. Does anybody know the correct parameters (settings) for a setup like mine?

[markopolo]

When you say loads - does that mean you have something connected to the solar controller Load Terminals in addition to the battery being connected to the solar controller Battery Terminals ?

[dvrdwn]

[QUOTE=markopolo;83081]When you say loads - does that mean you have something connected to the solar controller Load Terminals in addition to the battery being connected to the solar controller Battery Terminals ?[

Yes

[dvrdwn]

solar.png

This is how I'm wired up.

[cruising7388]

Originally Posted by dvrdwn

Attachment 6633

This is how I'm wired up.

In an RV application with battery storage to support coach loads, why would you want to connect loads directly to the controller that with reduced UV will be unable to support them? Aren't the load terminals on RV controllers typically unconnected?

[markopolo]

I agree with cruising7388 that the load terminals on solar controllers in RV use typically remain unconnected.

The topic has come up a couple of times but I don't think anyone ends up continuing to use the load terminals.

As to your question:

Originally Posted by dvrdwn

My charge controller is disconnecting power to all loads when the batteries read bellow 13.5. I,m assuming it,s because the settings aren't set correctly. Does anybody know the correct parameters (settings) for a setup like mine?

You're likely correct about it being a setting. If you have the add-on remote Tracer meter I think it will show what the error is.