Virtual "total system" charge controller (feature request)

Q&A and troubleshooting
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1

I have (2) SmartSolar MPPT 100/20 controllers running at 48V, charging (2) parallel 48V/105AH FLA battery strings, driving a 3000VA 120/240 split-phase inverter with a SmartShunt 300A in the middle. This all works well and has had a large portion of my home off-grid for nearly a year. I have two charge controllers because I have two dissimilar sets of panels on two different slopes of the roof. They are all working together via bluetooth VE.Smart networking. Synchronized charging works and the SmartShunt reports perfectly. Here comes the feature request:

When I connect (bluetooth on my smartphone app) into either charge controller, I get its current, voltage, watts, historical display, etc, and a “Total Network Power” indicator that sums its output with the other controller, which is nice. However, I cannot get a “total system” history in the daily graphs or the instantaneous charting. If there was a “virtual” charge controller that appeared in the display when you had multiple networked controllers, I could get information on maximum system peak power and many other statistics as a historical trending total of both controllers. Since my two banks of panels are on different roof slopes, the system peak happens at neither controller’s daily peak. This would be a wonderful addition to the application.

Secondly, I have the maximum battery charge rate set to 20A on each of the two charge controllers, but if system load is low, I often see the SmartShunt reporting a charge rate of 25-30A, which is more than I would like. Since I have a SmartShunt, and two controllers and everything is on a network, it would seem that I have all of the data gathering components that would then allow this “virtual” controller to have a maximum battery charge rate set in it that would actually set the maximum charge rate received by the battery as a sum total of both charge controllers with feedback coming through the SmartShunt. This seems like a very helpful addition to the already-excellent tool-set that could be done entirely in software with no changes or additions to the hardware that I can think of.

Your thoughts?

--Justin

2

The features you are wanting are available with the use of a GX device.

It requires processing and logic control, so would need a device to do so - a GX.

3

Yeah, I figured, but I guess I also figured that for devices that have the memory and processing capacity that the charge controllers already seem to have under the hood, they might be able to spare a few cycles and do something that doesn’t seem like too large a task.

--Justin

4

I think there are two separate use cases hiding in this request: live combined view, and durable combined history.

For authoritative daily totals/history, I agree that GX/VRM is the clean Victron path. That is the thing that can sit there continuously, collect data, and become the system of record.

For a lightweight local glance view, though, a phone/tablet app can combine nearby SmartSolar + SmartShunt data while it is running. That works well for the “what is my system doing right now?” case, but it does not make the MPPT itself store a synthetic combined history.

So I would probably split the feature mentally as:

• live combined dashboard: possible without GX, depending on the app/device support
• long-term combined history: GX/VRM or another always-on logger is the right architecture

That distinction helped me think about this exact gap when building Boardstrom.