Battery Lost Power too quickly

Tim Tim said:

Schmism thought you had 10AWG between your inverter and battery but I’m positive you mean from your solar panels to your controller. The cables from your inverter to battery look as though they are Renogy cables. Am I correct?

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no misunderstanding, 100% that wire is at best 1/4 the cross sectional area as a 4/0 it needs to be to carry 250+ amps (if we want to entertain the idea that inverter would actually put out that kind of power)

Koreypre said:

Thanks Tim. This was super helpful. Turning the inverter off had my battery back to full charge in a day or so. I didn’t realize bumping from the 1000W to the the 3000W inverter sucked a lot more power just keeping it in the on position. I was hoping I could upgrade to 3000W for the occasional time I needed a little more power but didn’t think it would affect anything else. I have purchased a 2nd 100AH Gel batter of the same kind and hoping to connect that this weekend. I eventually want to add 2 additional 200W panels but they are currently on back order. My cables are 10AWG. Do I need something greater? If so, what do you recommend? Secondly, someone else mentioned having fuse(s). I have one 20A fuse (not pictured) as part of the system. Will that suffice in your opinion? Are there any specific gauge cables to connect the batteries to each other? I appreciate the help!

PS - I think you were right about the incoming Amps cause it seems I am somewhere around 10 coming in during good conditions.

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Ok take a look at the system you are proposing. 3 x 200W panels equals 600W although you will not get the full output. Connect them in series and this will reduce the need for heavier cables so your 10AWG and 20A fuse are sufficient for that.

Tim Tim said:

Sry was just having breakfast . No, not if you have an adequate fuse between your battery and inverter. what size is it?

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Grape Solar 20A in-line fuse between solar panel and charge controller.

Tim Tim said:

Ok take a look at the system you are proposing. 3 x 200W panels equals 600W although you will not get the full output. Connect them in series and this will reduce the need for heavier cables so your 10AWG and 20A fuse are sufficient for that.

Series vs. Parallel

Learn about series, parallel, and series-parallel connections in solar panel systems. Understand why each connection type is used and how to set up your system accordingly. Discover the benefits and considerations of each connection type based on your specific situation.

renogy.com

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So I would connect both the panels as well as the batteries in series?

If you have a 12v inverter, you need to keep the batteries in parallel. With an MPPT charge controller, you can have a higher voltage from the panels in series as the controller steps it down to the appropriate level.

Koreypre said:

So I would connect both the panels as well as the batteries in series?

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No as I said you can connect the panels in series which will increase your voltage but the amps remain the same. This enables you to use the existing cable 10AWG cable and 20A inline fuse.

Then as CamelCase said, connect the batteries in parallel so you have a 12volt bank. The MPPT solar controller steps down the voltage to charge them at the appropriate voltage. Only if you had a 24volt inverter would you be able to connect the batteries in series.

Ok so now cable sizes. Solar panels to solar controller are ok as I said above.
It looks like the cables from the battery to the inverter are the standard Renogy cables that came with the inverter. I did ask you if they were but you didn't answer . I took a look at Renogy Australia and it says they are 25 mm cables so I’m assuming they mean that the conductor is 25mm2. To throw a cat amongst the pigeons as we say, the UK web site says they are 20mm cables so who knows lol. In all probability they are 4AWG

You said that generally that the 1000W inverter got you through 90% of the time. You need to know what the highest wattage appliance that you will be using and then we can work back from there. Alternatively we can size them for the full wattage of the inverter which will allow you to use any number of appliances up to the full wattage.