How do I check total amp output from all connected panels?
- Thread starter gnoeld
- Start date
Brett V
Mad Scientist
Your problem is measuring amps without a load. Refer to the specifications on the panels you're using and how you have them wired. Are they all in parallel, series, or a combination? A little more info will help.
You shouldn't need to measure anything to get the correct controller. Look at the specs of the panels and of the charge controller.
There are usually two key numbers associated with the charge controller.
1 - The max PV input voltage. You need to make sure the temperature adjusted Voc of your panel array is less than this max input voltage.
2 - The battery charge current. Multiply the controller's battery charge current by the bulk charge voltage you set. That will be the maximum wattage supported by your charge controller. Your panel array can have more wattage, to a point. This is referred to as "over paneling".
Some controllers will also have a 3rd restriction and that is a max input current. Make sure the Isc of your panel array is less than the controller's max input current.
I know going over the max input voltage will do a number on most SCC/inverters, but is the same true for exceeding the max input amperage by say 10%? Does it do major harm, or does the controller just cap the current at the max spec and no harm is done?
timselectric
If I can do it, you can do it.
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- Feb 5, 2022
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The SCC draws what it needs, and no more.
I posted this yesterday in another thread... Inverter max input per MPPT is 12A. I ran the numbers for my panels with 2 strings and came up with Isc (A)=12.86 and Imp (A)=11.94. More often than not I'd be under 12A. Should it go over will it damage the inverter, or will the inverter just limit the incoming current to 12A?
Thank you for clearing that up for me. This is what I thought was the case, but didn't want to damage something if I were wrong. Current is a measurement of flow, and if the controller is limiting to "X" amps, it would seem to reason that no harm could be done as it's not allowing additional flow.
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