Verifying Battery Charging from Truck with BMV-712 Shunt

[traveldawg]

Hi- According to Adventure RV in Shipshewana IN ( they changed our Norcold frig to a 12 v only) if you want to run a 12 v frig while traveling (who doesn't?) a 7 pin is not enough. They added a DC to DC charger (pictured above with 30 amp fuse to enable LFP batteries to be charged during travel. Your other equipment may well be fine just not able to pick up current draw. I'd suggest you check with Adventure RV ([email protected]) 260-336-0540 to discuss your specific needs. And your truck batteries will be dead if you leave the 7 pin connected w/o shore or solar power. Adventure RV is also a solar installer so they understand that as well. Also, our Lippert One Control shows the LFP batteries level of charge.

I run a residential refrigerator without bothering to charge my battery when traveling; for up to 8 hours and still have life left in the battery. It all depends on how big your battery is when it comes to having to charge it.

While the charge voltage/current from the 7 pin may not keep the battery at 100%, it will provide a minimal charge. So it is better than nothing. Again - this is very battery dependent.

I have a 200ah Li battery. It'll keep the rig running for at least 16 hours, more if not using the rig and just letting it sit. I do have a 30 amp DC-DC charger and associated wiring; I just choose to use the battery for the RV to keep it exercised when towing.

One would need to weight the pros and cons of adding a larger battery versus a DC-DC charger and the associated truck wiring (direct from battery via circuit protection to the RV) if one wanted to keep the battery fully or close to fully charged while traveling.

 

[Thorvald]

If you have a Victron Cerbo you can also add more Smart Shunts to isolate various DC loads or sources. For example on my trailer I have the main power converter panel feeding 12v to the trailer via ATC fuses with its own dedicated Smart Shunt. This way I can track which DC loads are which on the screen. More commonly though you would use it to measure a Alternator etc.

—-
7. All features and settings (victronenergy.com)

7.4.3. Monitor Mode​

If you wish to use the battery monitor to monitor individual DC circuits rather than as a whole-of-system battery monitor, you can change the "Monitor mode" setting in the "Misc" menu from "Battery Monitor" to "DC Energy Meter".

If "DC meter" is selected, you can select the following types:

Solar charger, Wind charger, Shaft generator, Alternator, Fuel cell, Water generator, DC-DC charger, AC charger, Generic source, Generic load, Electric drive, Fridge, Water pump, Bilge pump, DC system, Inverter, Water heater.

When connected to a GX device, the type, the current and the power is shown in the user interface, and this information is also available on the VRM Portal.

When the GX device is also configured as type “has DC System”, the GX does more than just recording and visualisation:

1. The power shown in the DC system box is the sum of power reported by all battery monitors configured as such. Having multiple meters can be useful, for example, in a catamaran, so that the DC systems in the port hull and in the starboard hull are being measured.
2. The DC system current is being compensated for when setting DVCC charge current limits to inverter/chargers and solar chargers. For example, when a load of 50A is being measured, and CCL by the battery is 25A, the limit given to the inverter/charger or solar charger is 75A.

See the GX device documentation for more information about these advanced features, especially refer to the Distributed voltage and current control chapter.
—-