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Eg4 3000 ehv-48 Inverter / charger PV Input Question

Funion

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Feb 14, 2022
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I recently purchased the new EG4 Inverter. I talked to Signature Solar and reviewed my array. I have 12 445w panels and want to have the in 4S3P. While I could have 2-6s strings I will be challenged by some shading so I felt best to have 3 strings. Anyway, they told me I cannot exceed 18 amps. Doesn't make much sense. If so, I need to select another inverter. Below are the specs. Can someone please help with the difference between "maximum input current draw" and 'maximum charge current (PV)? Thank you all!

1653044178501.png
 
Maximum input current draw, is the current limit from the PV array.
Maximum charge current, is the output current limit to the battery.
 
That said, I cannot exceed 18 amp from the solar array? If so, I guess I have to get smaller panels as each panel is 10a so I cant even combine two strings. None of the other inverters even list Max Input Current Draw on their spec sheets.
 
Every SCC has it in the specs.
But, you're rarely going to see more than 85% rated output. So, 2p should be fine. A little bit of over paneling is good for cloudy days.
 
I'd really like to have multiple strings to mitigate shaded panels dragging down the arrays performance. That said, if I went with three strings that would be apporximately 30 amps. At peak daylight on all panels, am I throwing away production?
 
The inverter you have selected is intended to have one string up to 18 amps and VOC of 500 volts. Your 3 strings VOC would be at the bottom of the inverters minimum starting VOC.
You are looking for one with 35 amps and VOC of 150.
 
Since I have 12 445w panels I think I will try 6S2P (as suggested by Signature Solar) for now and monitor its performance. As demand grows I’ll just add another SCC in parallel. Is that logical? I’m collecting sunlight through a pretty tight area in the woods. I’m guessing even in the summer I won’t get direct sunlight until sun is at 30° In the east and slowing lose it at the same point in the west.
 
This is a view at 8:00 am this morning facing south. Pole barn will be center north on the property. 1653227243766.jpeg
 
Short and simple........
You want to set up string VOC for about 375 to 400.
Then parallel strings to get 18 to 22 amps.
This will put you in the sweet spot.
Best case for you would be 12 panels.
(Assuming Northern hemisphere)
4 facing south east.
4 facing south.
4 facing south west.
2s6p

This will give you the most output throughout the day.
 
Thanks. I’ve now been looking at other SCC options and many, if not most, don’t list maximum input current draw just max current. Getting to that VOC range would have a lot of panels in series which is easy but not likely efficient for me. Nor do I need more than 12 with 5.3kw. This may just have to be trial and error after the install. Would like to avoid buyers regret of the SCC.
 
You can do a 8s string with your panels using the eg4. The other 4 panels can be handled with a stand alone Victron 150/35 in 2s2p configuration. At $325 for the Victron you need to consider as an alternative a second eg4 3000 would be $425 more and provide another 3000w of inverter capacity as well as the ability to add another 4 panels.
 
I am not trying to pick on Signature Solar or EG4 but their manual says 18 amps max and at the same time, they have a sample table showing 2 strings with 6 pcs in series. So, according to their own table, having 2 strings will results to approximately 20 amps which is more than 18. It also doesn't make sense why they sell groups of 10 solar panels. ? Anyway, it appears the 18 amp max value is not accurate according to their own manual and one can have a little more current. I purchased ten 445 watt panels and the first thing I noticed was the 18 amp max limit, so I cannot put all the ten panels in series (in order to stay under the 18 amp limit) because the voltage will be about 500 volts (50 volts more than recommend 450 volts input) and a simple solution would be to use only 8 or nine panels (not a good idea). I could also use all the ten panels in 5S2P but the current would be about 20 amps (more than 18 amp limit).
 
I am not trying to pick on Signature Solar or EG4 but their manual says 18 amps max and at the same time, they have a sample table showing 2 strings with 6 pcs in series. So, according to their own table, having 2 strings will results to approximately 20 amps which is more than 18. It also doesn't make sense why they sell groups of 10 solar panels. ? Anyway, it appears the 18 amp max value is not accurate according to their own manual and one can have a little more current. I purchased ten 445 watt panels and the first thing I noticed was the 18 amp max limit, so I cannot put all the ten panels in series (in order to stay under the 18 amp limit) because the voltage will be about 500 volts (50 volts more than recommend 450 volts input) and a simple solution would be to use only 8 or nine panels (not a good idea). I could also use all the ten panels in 5S2P but the current would be about 20 amps (more than 18 amp limit).
You can go over on the amperage, it's call over paneling. Good for cloudy days. But don't go over on the voltage. That's called releasing the magic smoke.
 
so its safe to run 20 amps to the EG4 3K converter?
Solar panels don't push amps, they just make them available. The SCC will draw what is needed, up to its rating. It won't draw any more than its rating.
This is only applicable to the amps. You can't go over on voltage. That let's the magic smoke out.
 
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