One controller or two?

[Tillsbury]

Ok, so I’m in the process of doing a solar installation. Four 120W panels, two each side. The two pairs are likely to be shaded or clear together, so I will be wiring the pair on each side in series — this will give me plenty of volts, and then the two sides in parallel, as it is more than likely that one side will be giving significantly more output than the other.

Victron’s calculator says that these in a 2s2p configuration require a Bluesolar 150/35 controller. I can then connect this with a ve.direct cable to my CCGX display.

Is this the best solution? Should I be running two smaller controllers, one for each side, since it’s likely that one or the other side will be shaded or at least not as efficiently pointed? Would two controllers give me more amps overall? I see that it would give me redundancy especially if both were capable of running the lot.

The thing I don’t understand is how I would connect two Victron controllers to the CCGX — I’m already using one of the ve.direct ports so only have one available, and I want to keep the canbus port free for a generator.

[john61ct]

Yes a 75/15 per panel pair for each side will be fine.

Not sure about that last issue https://www.victronenergy.com/live/ccgx:start

[FlyingScot]

Separate controllers for each side will likely harvest the most per day. Plus if one fails you have 50% output.

[Tillsbury]

So does anyone have advice about multiple controllers with a ccgx? I can't find any documentation that advises what to do when you want to connect a bms, two solar controllers and a generator. Yet surely most installations have at least that?

[FlyingScot]

Originally Posted by Tillsbury

So does anyone have advice about multiple controllers with a ccgx? I can't find any documentation that advises what to do when you want to connect a bms, two solar controllers and a generator. Yet surely most installations have at least that?

I think they use this.

https://www.victronenergy.com/access...-usb-interface

"With this cable it is also possible to connect more than two VE.Direct products to a single CCGX."

[john61ct]

through a USB hub

[Tillsbury]

Ok, so a ve.direct to usb converter and then hub into the ccgx as the number increases...

Interestingly, it seems that two 75/15 controllers and two cables is significantly cheaper than one 150/35 controller...

[chuckr]

We have 4 panels on top of our bimini with about 550w. We just increased to that wattage as we had a smaller panel and upgraded it. But we have only one controller - a BlueSky 3024i - we did talk to BlueSky to make sure it was not overloaded - We do have a spare controller on board from when we upgraded but I guess I am a simple guy on why do I want to introduce more complexity when I do not have to - just me I guess

[Kenomac]

We use five controllers for our five panels, so I recommend that you use four instead of two.

[Frugal]

FWIW.

I am using 10 by 80/90 watt panels in a 3 3 4 parallel configuration through two PWM and one MPPT regulators which allows for:-
1. Cheaper regulators.
2. Regulator failure redundancy.
3. Solar panel failure redundancy.
4. Smaller panels to reduce their vulnerability.
Also by having a large amperage meter in the main battery bus-bar to monitor charge / discharge rates, it is a simple test to check the output of each panel by temporarily shading them one at a time.
If you can afford the room it could be cheaper to up the panel output and use PWM regulators as against the MPPT's.
Cheers

[john61ct]

By cheap, do you think $120 for a BT-managed, customisable, seaworthy MPPT Victron with a 5-year warranty is expensive?

[sailorboy1]

Just 1 mppt controller and let it do it’s thing

All the rest is theory and chasing the buts, ifs, maybes in order to spend more money and make it more complicated than it needs to be

[briblack]

Two controllers, definitely. Redundancy is often very much appreciated "out there". We're running two pairs of 250 watt Kyocera panels. Each pair is separately routed to it's Morningstar Tristar MPPT controller, and then they're simply paralleled. The controllers are both under a Morningstar remote display. I can't say enough good about the choice of Morningstar.

[SolarBiZ]

Connecting more than two devices to your CCGX using VE.Direct

First of all, note that the maximum of VE.Direct devices that can be connected is 5 for the CCGX. How they are connected, so direct, via USB or via CAN, does not change the maximum. See here for the Venus GX, Octo GX, and other limits.

Option 1: Use the VE.Direct to USB interface. The CCGX has two USB ports. Use a USB-hub when more than two USB ports are required.
Option 2: The BMV700 and BMV702 can also be connected using the VE.Direct to VE.Can interface. Note that the BMV712, MPPTs and VEDirect Inverters cannot be connected using this canbus interface as it does not translate the data into canbus messages. When using the VE.Direct to VE.Can interface, make sure that the VE.Can network is terminated, and also powered. For powering the VE.Can network, see Q17 in our data communication whitepaper.

[john61ct]

"our" meaning Victron, correct?

I think this is just copypasted from their docs right?