The MPPT’s will limit themselves. I also strongly believe it is best to use 3 seperate small MPPT’s in case of shading. This will give you the maximum possible power is any shading condition. It also allows you to use thinner and therefore safer cables. 3 x 100/30 would give you 360W for every panel.
This is very interesting! The panels are actually 440w each. There are 3 but I might add a fourth later.
I wonder how small a cable can be used given a 30’ run?
But I come back to the same basic question, so each panel is its own array with it’s own controller. Does that many the wiring is separate and distinct right up to the battery? I’m guessing I would need 3 cut-off switches then.
I really like the idea of having each panel able to create as much as it can given it’s light. I’m a big fan of efficiency in that respect and doing the extra wiring is not a big deal. The 150/85 can be returned and the work has not started yet.
I don’t want to pick a fight with anyone, but for anyone coming across this thread in the future: 12V sucks for many reasons, not the least of which is MPPT sizing. You could have used a 150/45 for the same solar panel configuration had you used a 24V battery bank. It’s even better at 48V, though a little more limiting in the DC-DC charger range offered by Victron at the moment.
I think it’s smart to mention that. When I replaced my inverter last winter I should have seriously considered shifting over to 24V. This is an in-place setup (RV) so my thinking remained in the 12v world. Had I known better, I would have used a 24V inverter and changed the 4 6V batteries to that they were at 24V and lived with it as is (was) with an eye to the future.
I was encouraged though, as I realized the solar controllers support both 12v and 24v. There’s also no issue with the Cerbo. So it looks like at some point down the road replacing the Multiplus and cabling would get me to 24V.
So I think it was really smart to say what you did. Had I read that last winter I might have bought the 24V inverter instead and been in a different place.
Back to my question, if I use 3 controllers are they totally wired independently all the way to the battery? Would that mean I need 3 cutoff switches? Anything else I should be concerned with?
I haven’t read the entire thread in detail, but are you asking are you asking about using three small MPPTs (one per panel) vs one large one? If so, yes, you would have three pairs of PV wires coming down the roof to three independent MPPTs, each connected to the main DC buss.
That’s exactly what I’m doing/thinking. I guess I would need some type of bus bar or something to make battery connection cleaner.
Thank you. According to Victron my CerbGX MK2 only has 3 VEDirect Ports. I’m pretty sure I’m using one already. I’d prefer to have my solar controllers on VeDirect cables rather than bluetooth.
Is there any way to expand the number of VEDirect connections?
Yes. There is a company in Italy that makes them. See here: https://www.duppa.net/product/usb-quadport-ve-direct/
Intelligent Controls in MT sells them.
You can use usb to ve.direct cables however they can get expensive, duppa 4 port ve.direct linked above along with their much cheaper cables usually ends up being cheaper especially as you add more devices.
Us distributor as duppa no longer ships to US from Europe.
So, if you don’t link them with Bluetooth basically you need a hub?
To connect to cerbo or pi running Venus os the sccs have to be hardwired (ve.direct or ve.can).
The ve.smart bt network is generally for smaller systems without a cerbo, perhaps shunt+scc+charger etc.
10AWG is enough for both sides, battery-Smartsolar 100/30 and Modules -Smartsolar. Battery side should be as short as possible. Use a 20A Midi Fuse for each module and a 50A Midi fuse to the battery This fuse boxes can be used with removed insulation without anything. They ars available with only one fuse too. Breakers are inadvisable. The wire from fuse box to battery is bigger size. in yor installation the minus wires are not connected to the battery. They ahve to be connected to the shunt (system). A longer M10 Srew is necessary. The connection from shunt (battery) is a bigger size too.
Wow - thank you sir !!
I’m looking at adding another panel as the roof has lots of room left…
they have to be connected with isolated interface cables. Each MPPT and the smarshunt. You can use a USB Hub . I think the Multiplus ha to be connected via MK3 Interface.
To each MPP you can us 2 Panels connectes in series. Or one more 100/30 for a max current of 120A
Interesting…it looks like there is room for two more panels - so that would be 5 total. So I can run two panels in series off of the single 100/30 controller? It’s not too small?
That would give me more flexibility should I decide to add two more panels.
I have another dumb question though, it’s cheaper to buy the 100/30 controllers without bluetooth. Is there any way to configure them if they were connected via the Cerbo using VeDirect cables?
Just to be clear, I’m not trying to monitor it, but configure it completely. Otherwise I have to send back 3 or 4 of them.
Yes you would drill thru the cerbo ( victron connect-r) to adjust the settings just like you were within bt range of a smart solar.
This would also be one of the methods to enable bluetooth if you disabled it on a smartsolar scc.
The Controller will Limit the current. But by overpanneling it delivers Double power until this limit is reached