Upscaling the solar generation on our property 2

[Joeboy]

I will look at the charger. As the panels will have an open circuit voltage of ~150V I'm thinking of running DC from the roof down and along about 50ft to the charger next to the battery, which tops out at ~53V. Can the charger just splice in to the DC cables between the growatt inverter and battery and the BMS control both the charge from the fit system via the growatt inverter and DC from the new panels and charger or is it more complicated than that?

Let's see if the sig works

Sig looks good and yes to splicing in between the inverter and batteries. The Victron controller has a settable top end so it can be used across many set ups. Once you set that it will switch off when the set voltage is reached in the stack. Once that voltage drops it will fire up again. Its a very nice bit of kit plus it has Bluetooth functionality so easy to control via smartphone. I run five strings of three panels through mine with a 5.1kW max potential. The strings run at 115V so just over 42A. I had the 35A version before but grew the system so stepped up to 150/60.
https://vanjunkies.co.uk/products/victr ... AEQAvD_BwE

Smart solar is the Bluetooth version whereas blue solar is not.

[openspaceman]

Thanks Joeboy, sorry for delayed reply I have spent an inordinate amount of time changing out an old 2 gallon syphonic loo for a modern 6 litre one, every thing seems to take me a long time now.

Plumbing I am just about competent to do, electrical stuff is a bit beyond me.

So if I set the MPPT charger to 0.1V less than what the growatt charger peaks at it will only charge if my FIT system is not filling the battery and everything on the growatt system will be safe? I would still like to know what smallish (2.5kWh) battery I could parallel with my growatt as I cannot fathom why the growatt inverter should be limited to a maximum of 12kWh batteries. I don't want to compromise the warranty on the growatt system.

Can those victron chargers also be set to current limit?

[Joeboy]

Thanks Joeboy, sorry for delayed reply I have spent an inordinate amount of time changing out an old 2 gallon syphonic loo for a modern 6 litre one, every thing seems to take me a long time now.

Plumbing I am just about competent to do, electrical stuff is a bit beyond me.

So if I set the MPPT charger to 0.1V less than what the growatt charger peaks at it will only charge if my FIT system is not filling the battery and everything on the growatt system will be safe? I would still like to know what smallish (2.5kWh) battery I could parallel with my growatt as I cannot fathom why the growatt inverter should be limited to a maximum of 12kWh batteries. I don't want to compromise the warranty on the growatt system.

Can those victron chargers also be set to current limit?

The only current limit that I know of is by size of array or topend limit of the charge controller itself. 35A 60A etc, there may be smaller units. My unit is set a couple of 1/10th'sV below the recommended upper settings for my Pylontechs. No reason why the same strategy wouldn't work on the Growatts. Although I don't know that battery...

[openspaceman]

I was just about to order the Victron charger, as the panels arrive on Monday, when I see the mention of GX devices, do I need one of these? I was happy just to let the charger and BMS sort out the charging and let them simply disconnect the panels (which will never happen in winter).

I shall have to improvise a mounting system with the base being two scaffold poles. I'll start with the array flat and see how that goes.

[Joeboy]

I was just about to order the Victron charger, as the panels arrive on Monday, when I see the mention of GX devices, do I need one of these? I was happy just to let the charger and BMS sort out the charging and let them simply disconnect the panels (which will never happen in winter).

I shall have to improvise a mounting system with the base being two scaffold poles. I'll start with the array flat and see how that goes.

What's a gx device, new to me?
Edit- Ah, fanciness, your call...

[Andy]

You can run a Victron system from a raspberry pi as well as its all open source. However you have less connection points on that. I'm going GX for the hopefully ease of use. I'll then run all my charging scripts from a raspberry pi.

[openspaceman]

I take it Joe manages without. Andy why would I want anything else connected, my main 4kW array and ac coupled battery runs all by itself and the additional array and charger will just top up the battery, what else would I want?

[Andy]

I take it Joe manages without. Andy why would I want anything else connected, my main 4kW array and ac coupled battery runs all by itself and the additional array and charger will just top up the battery, what else would I want?

Probably only if doing many mppt trackers/inverters etc It might give you more oversight of what is going on in your system but you might be able to see that anyways. I'm no expert. In a full Victron setup it communicates with the cloud and also lets you log in to a webpage locally to see what is going on and change settings.

[Joeboy]

I take it Joe manages without. Andy why would I want anything else connected, my main 4kW array and ac coupled battery runs all by itself and the additional array and charger will just top up the battery, what else would I want?

As you say, I have no reason to go further into Victron world but some might want to add on more later? I think you'll be OK with the smart solar charge controller. Exciting times!

[openspaceman]

Thanks, charger ordered, I can't run to a new pylontech battery yet and the electrician hasn't turned up today as expected but I should be able to have a trial run with some tractor batteries in series if I can figure out the charger controls.