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General Category => System Design and Layout => Topic started by: elbraaapo on February 27, 2024, 02:48:27 PM

Title: Classic 200 sizing Question
Post by: elbraaapo on February 27, 2024, 02:48:27 PM
Hi there, new to the forum, light on solar knowledge and looking for some advice. Sorry bit of a story up front.

Wife and I live fully off grid for last 7 years in BC Canada. Purchased a full system from a local company no longer around and I've been wanting to add some panels. Problem is I can't find any that will "match" with my older panels. I'll list system specs below. I've phoned around to a lot of other companies and nobody has any that can match up.

Obviously there's several options available, add another controller with its own panels etc. But budget wise I've decided to just get a full new set of panels to try and maximize the classic 200 and sell existing panels seems the best from a dollar/value perspective.

One of the local CO's I called has the following 2 choices at what I believe is a great price (relative to my discussions with other CO's).

- Longi 360w mono
- Jinko 465w bi-facial

His calculations show 12 of 360w working for my classic 200, or 9 of the 465w to work. When I plug in the panel info into the classic calculator I get both showing over wattage as excessive with the 360's at 1.1 and the 465's at 1.2 which hopefully I've done correctly (pics attached). I do want to maximize my output and get as many panels as I can into my single classic 200, but is there a concern here as I don't want to wreck anything in the system or risk fire etc. I see in the fine print they recommend going to 2 CC's if over 1.2.

Here is my current setup circa 2018:

- 6 Vikram Eldora 72.315.03 panels, 2 strings of 3 panels
- midnight Solar classic 200 cc
- 4448 PAE magnum inverter/charger
- 8 silicon gel batteries in 2 strings of 4 batteries for 48v (labelled as 150ah but told they tested at 170 so not sure there)

Thank you for any thoughts or advice.
Brent
Title: Re: Classic 200 sizing Question
Post by: ClassicCrazy on February 27, 2024, 07:26:26 PM
I think it has been said that it is okay to go over some on the power and the Classic will just limit it to it's max. And of course that would only be on the days when the PV is actually putting out it's max , which around here is only on very cold days in winter with bright sun and low humidity in the air.
But I am sure someone else can clarify .
Larry
Title: Re: Classic 200 sizing Question
Post by: ClassicCrazy on February 27, 2024, 07:49:12 PM
Also I should mention that if you find other panels that add up in voltage within 10% of the voltage of your existing pv - you could add another string on what you already have. I didn't do any of the math of your present system.
I added 5 135 watt pv string  to 3 240 watt pv  string because the voltage was close to the same.
If it was me, I would get another controller instead of getting rid of your old pv because it is nice to have too much PV for overcast days . Since I have added more PV  I have more power than I can use on sunny days, but it is great that I can break even on many of the overcast days . It cut way down on generator run time. Also I heat water now with all the extra PV power I have. Also PV is way down in cost so doubt you could sell used ones for much these days since there are so many used pv on the market now. But maybe not where you live .
Larry
Title: Re: Classic 200 sizing Question
Post by: elbraaapo on February 27, 2024, 08:28:29 PM
I should have mentioned I do live beside a lake so in the winter months we get a ton of lake cloud and heavy humidity. Some days just thin enough cloud that I can tell how bluebird it is everywhere else except at my house lol.

I had actually thought about purchasing a smaller less expensive controller and using it for the existing array and use the 200 on the new panels as one of the paths to take. But then I thought about the costs adding up more than we'd like to see by the time I add more wire/ electrician time/controller and for some reason I thought it might be an issue when I hopefully add in a micro hydro controller as well??? Albeit a very small system, hoping to get 3-4amps (@48v).

So maybe the 360w mono's would be better (even though I'd like to go bifacial for our winters) since they don't risk going over wattage as much as the 465's do.

I really need to get my classic so I can view its power history easily lol.
Title: Re: Classic 200 sizing Question
Post by: ClassicCrazy on February 28, 2024, 09:55:35 AM
How far are your pv from the controller ?
Is that the wiring costs you consider ?
Larry
Title: Re: Classic 200 sizing Question
Post by: elbraaapo on February 29, 2024, 12:02:28 AM
Quote from: ClassicCrazy on February 28, 2024, 09:55:35 AMHow far are your pv from the controller ?
Is that the wiring costs you consider ?
Larry

I think it's 130' of wiring if I recall. 
Overall cost of additional panels, install etc. Budget restraints this year as we're planning to subdivide as well as add a small micro hydro.