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Has DC system - how to setup alt chargers

I have a Cerbo GX, 24v system, Quattro 8000 with a SmartShunt for the 24v. I also have a 12v system with a bmv that is powered using 2 Orion 24-12 TR chargers. The 24v side is also charged using a 12-24v Orion TR when the alternator is running. How do I show the correct voltage and amperage in the GX for both the 24v battery and the DC display?

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ben answered ·

You cannot display two BMVs on the main UI of one Venus device (Cerbo GX, Venus GX, CCGX).

You can hook up a second BMV and see the data in the Venus menus, though, if that would work.

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I read that. I'm just trying to figure out how to get the DC reading to reflect correctly.

What does "reflect correctly" mean to you?

Did you try plugging both BMVs in? You'll simply see two of them in the menu of connected devices. You can click into either of them and look at their detailed values.

Maybe I don't understand what the DC main display means. I want the DC to reflect the 12v DC devices, the 24v to 12v Orion chargers and the 12-24v alternator charger. Basically all the 12v side combined plus and nagative amp/watts.

Where it says DC power

The "DC Power" box, if turned on, is just an accounting true-up calculated by Venus.

In a nutshell, it calculates that box as roughly

Shore In - AC Loads Out + DC In + PV In

Shore In and AC Loads are calculated using current estimators inside the inverter. DC In is measured using the BMV on your 24V battery. PV In is measured inside the solar charge controller.

The system assumes that any excess power not accounted for in the above is being sent to other DC loads.

That's only right, of course, to a limit. Any losses are also attributed to "DC power" in that true-up. The current sensors themselves have accuracy error. And the numbers will almost never add up perfectly, because the code that does the accounting true-up doesn't run at the exact moments that some of the other values are posted and displayed.

I don't have a picture of your whole circuit to reference here, but I think it's possible that you can infer some of what you'd like to see from the built-in metrics. But probably not all of those values.

Ok gotcha. Sounds like u r a dev for victron. An idea to allow Venus to scale better. Allow each BMV connected to represent another DC load. I have no problem buying multiple shunts so that I can represent my battery banks. This would be a win/win since I get decide what is important and you guys just sell more shunts. Any idea of companies that customize Venus? I like to learn but I'm a c# developer and don't have much time to devote to this.

I'm not a dev for Victron, just an end user who occasionally tinkers. :)

The idea is good -- more modularity and flexibility in the UI would be pretty nice. It gets complicated quickly, though, because with multiple shunts you soon devolve into needing to write custom logic to add/subtract/combine various values. Each system could have its own unique things like that. I think the feature as you've laid it out is pretty substantial.

For third-party help, you could post your needs in the Modifications space and see if anyone there might bite on a custom project.

If you're interested in an off-Cerbo visualization, I might be able to help you get started there. (I do it this way, because the built-in UI is too limited.)

I just want the main menu to reflect the 2 shunts. Anything you can do to help would be greatly appreciated. As far as logic I think it could scale to 3 shunts since there are 3 ve ports, main (left), DC load 1, DC load 2. I don't want any deductions because it's more about seeing what's going in/out per shunt that I wire up. The main screen would show 2 small boxes where the DC power graphic is.

If you can get the shunts to register on the menus as added items, it's definite possible just to write a few extra values onto the screen in a box somewhere. A number of people have augmented their QMLs with extra data like this (e.g., displaying the AC current and voltage in addition to the power).

Can you tell me how to get started doing this? The shunts do show up settings>battery monitor when I plug both in.

Go pull up the Venus OS wiki docs and have a read through them. ssh into your Venus device and find the qml files. From there, you can either edit them by hand or pull them onto a machine and get the whole Qt editor suite.

Hi Ben, I got ssh and superuser setup for the access level but I can't ssh. I set the root password as just 9999 but getting permission denied when I ssh. Any ideas?

Disregard I figured out I had to set a password of 6 characters or more. lol

Ben, I wanted to elaborate on what I am looking to do...

Here is the equiment I have...

24v Solar Bank Chargers

12-24v Orion TR 30amp Alternator to 24v Charging

8000va Quattro 24v

250/70 MPPT

12v DC House Bank Chargers

24-12v Orion TR 30amp House Battery Charging

24-12v Orion TR 30amp House Battery Charging

12v Truck Bank Chargers

24-12v Orion 70amp Truck Batteries Charging

What I like to show on the main screen of the GX Screen is 12v House and 12v Truck where the DC Power is currently sitting. This way I have 3 indicators Voltage/amps solar bank, Voltage/amps house bank, Voltage truck bank.

We are only going to monitor the voltage using the 12v smart shunt for the truck battery but I like a full readout of the voltage/amps of the house and solar banks.

Using a smart shunt the house 12v side should show + Orion 30amp + Orion 30amp + 12v DC Loads

Using a smart shunt the 24v Main battery should show just the 24v shunt without trying to interpret the loads using the quattro.

Does this sound doable? Am I missing anything?

solarsetup.png (1.4 MiB)

I think I follow you on the two 12V banks, as long as each has a shunt into which all the loads and sources are funneled. Those shunts will show the total (delta) current into or out of those banks.

The 24V shunt part I'm not sure I understand. What does "without trying to interpret the loads using the quattro" mean?

For the shunts you do have hooked up to CGX, do you see values in the menus that make sense to you?

What shunt do you have on the 12V truck bank?

What does "where the DC Power is currently sitting" mean?

Why do you not care to see the SOC of the 12V House Bank? (You say just current and voltage?)

If the data you want are already showing up on those menus, you can definitely get it onto the screen some how, some way.

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