diy solar

diy solar

8 x 415Wp panels. How to proceed?

hmm but with the 250/60 would cover things while retaining this feature in where one need only 5 volts + to start charging the battery
and the amps would also stay within range
 
hmm but with the 250/60 would cover things while retaining this feature in where one need only 5 volts + to start charging the battery
and the amps would also stay within range
If only someone had mentioned that earlier. :unsure: Scroll back to post #3. Ha...
 
and in many ways this is not even to be considered going back and forth. as the multiplus II still needs a charge controller so I think we are now narrowing down in more detail
 
The VE.CAN with a Cerbo is great, and allows you to do nice things when you have a Cerbo or Color Control
Note: there now is a Cerbo-S, which is a fully functional Cerbo, but it only lacks the tank sensor inputs and BMS.can. If you don't need any of those it saves another $100 or so.
The color control is cheaper, but it lacks some connections, and has a lower resolution (And less memory) compared to a Cerbo. But for basic functions its still sufficient.

I'm a fan of the Cerbo units, since they also provide remote access using victronconnect on your phone through their VRM, and allows remote monitoring of the setup. And with the addition of eg Ruvi tags you have temperature monitoring as well, and can apply actions based on it. And with the relay ports you can also enable/disable things eg run a water heater on excess solar, or disable water heather if the SOC is below a certain threshold.

The 150V MPPT is even cheaper, but it does require more strings (3 panels in series usually max).
I'd love to love Victron but the sheer madness of all of the different communication protocols drives me crazy. Bluetooth, wifi, smart dongles to produce bluetooth, VE Can, VE Bus, VE Direct. I'm sure I've forgot a few....

Plus they've got multiple products that do maddeningly similar things with very subtle differences. EG: the GX line. I had a bit of a temper tantrum on the Victron Forum about all of this and FWIW Victron themselves totally agree with me. HA

I've done a few small systems with them and the learning curve was atrocious. Still I just installed the Smart Shunt on my system so the Blue cancer is setting in on me... LOL.
 
hahahha yes borther. If it was not for that comment I would not be thinking about victron to begin with so thank you.

pleasee excuse me going back and forth some times as I am way out of my comfort zone here.
It's good. We're all just hurdling through space to our death at ~180,000 MPH. Might as well enjoy the ride.
 
I do not dare to when using a 150/35 victron mppt. because I have been warned that we need to take into account the 10% extra Voc that can incur on cold days. I have been warned twice already.

So that would mean 167.2 Voc. now if the victron MPPT can deal with that and just limits it to 150 then I am game
How cold does it get there? 3 in series are going to give you just over 112 volts. Your issue is the 35 amp output rating. You need a much higher output controller.
 
I think its reasonable to calculate with -10 celcius here (Netherlands)
It might get (very occasional) colder during the night, but once there is sun the temperature is already increased.

Off course you need to carefull calculate the exact voltage. With most panels having a Voc of around 40V, with 3 in series you're within the 150V limit.

35A at 50V+ (Average voltage of a 48V bank) is about 1750Wp. But you can overpanel, and especially with a east/west setup, the max PV output is rarely archieved.

I personally wouldn't have any issues with connecting 2000-2200Wp on a 35A controller.

Multiple controllers if you have multiple orientations (Eg 1 west and 1 east controller) or the bigger version like the 150/70 or 150/100 if you have more panels. (thus 2x 35A controller for those 4000Wp when east/west orientated, or 1x70A if they all are facting the same direction)
 
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I will report back once I have figured out how and where to put those panels (maybe even 9 as suggested if I can find a similar panel. This particular one has sold out in the meantime). So I can see them in action in winter time. I guess that will provide us with much needed empirical data on an overcast day such as it was today.
The end goal still is to have some trickle charging of an 48V battery array even on days like these.
 
I'll be asking around here on the forum as well on how to off grid the on grid APsystems. I feel so cheated (read I did not do my homework when I went fo on grid back in 2016) that all my panels do exactly nothing when the grid goes belly up.

NOw one might argue, ahh don't panic it rarely happens. Well, we've had 2 power cuts in 2 years time. one lasted for like 2 hours. And somewhere else here in the NL recently there was a 24 hour black out so I have been told.
 
please see some of the responses here
on how to get my already in place PV to play nice.

Does that change anything in our discussion? I think yes as I have not read about AC coupling yet in both the victron and growat manuals.
 
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