I have a Cerbo GX on my boat in another country, so I do not have access to the physical system.
The boat is connected to shore power and has AC loads and DC loads. The Quattro 24/3000 is in the “ON” position.
The Cerbo is connected to the Quattro and to a BMV-700
The AC load is the Quattro and one 220V outlet powering a camera
The DC Load is the Cerbo, a camera, a security hub, and a 4G modem
When I first left the boat the DC load was showing around 4-5W which made sense to me as it was about the load I expected from the devices connected to it. However, 6 weeks ago the DC load dropped to zero and has stayed there. The devices connected to DC are still working.
Could it be that the VE.Direct cable from the BMV-700 to the Cerbo has come loose? Would that explain this behaviour? Alternatively is there any configuration that could have changed it? I have not made any changes to it myself.
Secondly, and most importantly. Can I rely on the battery voltage being shown on the VRM portal? It is showing consistently 27.00-27.02V and the battery at 100%.
Does this voltage value come from the Quattro monitoring the batteries?
Knowing the battery state of charge is the major reason I installed the Cerbo as I have had problems with batteries becoming fully discharged in previous seasons.
The Quattro is showing as going into absorption mode about every two weeks for a couple of hours
Thanks, Brett
The BMV-700 is a battery monitor it measures the current into and out of the battery. If you have battery volts and current and SOC to the battery all is fine.
In this case, the DC load is not actually measured so it is inferred from all other data and is not entirely accurate. See this FAQ describing this.
DC load box calculation if not measured
Do check via remote console that in system set up that you still have “Has DC loads” enabled.
Thanks for your reply.
Unfortunately, I did not turn on Remote Console before I left the boat. I will remember to do that this time. So I do not have access to it via the VRM Portal.
However, I do have a DC Battery Tile and a DC Load tile on my VRM Overview so I think the “Has DC System” is on
I have looked at all the Battery Monitor Widgets and they do not show any activity during the normal day. However, when the Quattro goes into Absorption Mode it does show an increased voltage, and amps flowing into the Battery Voltage and Current Widget for the period that absorption occurs. Battery SOC stays at 100%.
So I am confused, one explanation could be that the DC devices that are running are not connected properly to flow through the battery monitor shunt. I will need to check that when I am on the boat.
However, I think I am comfortable that I am getting a correct reading on the battery voltage. Which is the most important thing.
Thanks
As VRM is showing the DC tile it is set to on, but you now know that this is calculated so is not 100% accurate. You also know the monitor is connected to the GX device.
Another couple of useful FAQs to read are
Monitor wiring if it is not reading properly
Monitor jumping to 100% erratically and correct synchronisation settings