I am getting ready to replace my RV house batteries with AGM’s and would like to install an IP65 smart shunt when I do. One of the issues I have it that I have 6 batteries. 4 are on the left side of the RV and 2 are up front. I am trying to find out if it is possible to make a shunt work in this situation and if so what would be the best way to go about wiring it in. I’ve attached to simple diagrams (sorry they are rudimentary). One is how the batteries are currently wired and the other is how I thought about wiring in the shunt. Looking for some input from the experts out there. Any assistance you can provide is greatly appreiciated.
The SmartShunt will work properly as you have shown.
The potential issue is the inverter is usually the largest load and you have now made its supply potentially longer. I suggest you connect the SmartShunt to the upper right battery rather than the lower right battery. You could also connect the left battery to the SmartShunt battery side so that has an easier path to the SmartShunt and inverter. Note, the cabling from batteries to SmartShunt needs to be large enough for the inverter.
Thank you for your response and input. I’ve attached and updated diagram based on your recommendations for review. Couple quick questions for you.
Not sure what you mean when you say that I have now made the supply potentially longer for the inverter. Are you meaning that I made the cable run longer. I know its not shown in my simple diagrams but the length of cable running from the shunt to the inverter will be the same cable that is used now running from the battery to the inverter.
What gauge do you recommend for running from the battery to the shunt. 2awg or 4awg. The inverter I am running is a 2000 watt inverter. Also what gauge would you recommend running from the bus bar to the shunt. The bus bar will be installed up front by the 2 front batteries and I will run a negative cable from the bus bar to the shunt. I’m figuring a 8-10 foot run. I plan on installing a 500a shunt
Really appreciate your input as I want to make sure I get it done right.
In terms of the comment on it being longer, it is not just that it may be physically longer, which you say it may be but not significantly, but also extra crimps, connections, so just trying to get power to it as easily as possible.
For 2000W inverters at 12V Victron recommends 70mm2 = 2/0 AWG up to 15ft and for 24V, 35mm2= 2AWG.
For the shunt to bus bar depends on your load. Have a look at Victron Wiring Unlimited free book. It is also available as a pdf.
