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Jmurphyf1
07-31-2021, 01:16 PM
I have 2 12v 650 cca batteries what 6v should i replace with in travel trailer.

wiredgeorge
07-31-2021, 01:29 PM
I have 2 12v 650 cca batteries what 6v should i replace with in travel trailer.


Murphy, go to the UserCP and find the signature button; make a signature with year, make and model of your camper as well as the same for your tow vehicle. This will allow your questions to be answered with a bit more context. Welcome to the forum and soon some smart folks will be by to tell you which batteries are best.

chuckster57
07-31-2021, 01:32 PM
Welcome to the forum :wlcm:

The 12V batteries you have now are not meant for RVís. Since you want to change to a pair of 6V batteries you want Golf Cart batteries. You might need a different battery box as the 6V are a different size. They also get connected differently than a pair of 12V batteries.

MarkEHansen
08-10-2021, 03:59 AM
As Chuckster57 mentioned, you really want true deep-cycle batteries for use in an RV. Batteries which include CCA (cold cranking amp) ratings are not true deep cycle.

After a lot of research, I elected to go with dual 6V GC2 (Golf Cart) batteries. They have reasonably high AH ratings and are not too expensive. Here are a couple examples:

https://www.costco.com/Interstate-6-Volt-Golf-Cart-Battery.product.100476406.html

https://www.samsclub.com/p/duracell-golf-car-battery-group-size-gc2/prod3590228?xid=plp_product_1

I'm currently using the Interstate but plan to switch to the Duracell when the time comes.

Remember that when moving from dual 12V to dual 6V batteries, the wiring is different. The 12V batteries are wired in parallel while the 6V batteries are wired in series.

Next, you really want to make sure you keep the batteries maintained properly, including not discharging them too far. A great tool to help with this is a shunt-based battery monitor. I use the Victron Energy BMV-712 Smart battery monitor:

https://www.victronenergy.com/battery-monitors/bmv-712-smart

Good luck.

Vinnie
08-10-2021, 07:29 AM
Unless it's too complex to do quickly, please explain "shunt" installation for a battery monitor.

flybouy
08-10-2021, 07:37 AM
A shunt is a metal bar with a coils of wire wrapped around it. The metal bar has one end attached to the battery post and the cables that were attached to that post get relocated to the other end of that metal bar. Then the display panel shows an interpretation of what the winding around the shunt is recieving.

MarkEHansen
08-10-2021, 07:46 AM
Right. The shunt allows the battery monitor to track exactly how much current is going into or coming out of the battery. It allow very precise tracking of the state of charge (SOC) of the battery.

Vinnie
08-10-2021, 07:59 AM
Ok so the shunt itself is a part of the meter. Something else to buy and install. Seems, at least with the whiz-bang electric control systems (like iN-Command), that would be integrated.

MarkEHansen
08-10-2021, 08:26 AM
It's not. The majority of consumers don't care about batteries. A real battery monitor is an add-on.

JRTJH
08-10-2021, 08:44 AM
Ok so the shunt itself is a part of the meter. Something else to buy and install. Seems, at least with the whiz-bang electric control systems (like iN-Command), that would be integrated.

Looking at it from the "builder's perspective", that would mean an additional $1 or two in cost. If the manufacturers are looking at the "cheapest possible components to build a trailer to sell for the most profit" then adding even a nickel to the cost of the lowest bid items is "cost prohibitive"....

Then, when you consider that most people use their trailer in campgrounds with full hookups and are "roughing it" when they have to park in a site with water/electric only, those types of features wouldn't matter to the "average retail customer", so don't look for a "built in battery use monitor feature" in Keystone products....

Now, if you're looking at a Bowlus Terra-Firma, a "full feature electrical OTG system" is standard. Starting price, $265,000.... https://bowlus.com/terra-firma/ That trailer comes "standard from the manufacturer with enough lithium batteries to run the air conditioner for "up to 16 hours" and it has the "instrumentation" to monitor how much battery power has been used as well as how much is remaining...

Keystone's most expensive "luxury fifth wheel" trailer costs about 40% of that at $110,000. The average Keystone trailer MSRP is in the $35,000 range and sells for around $28,000.

Few of the "luxury features" are included in any Keystone, expecially those that don't matter to the "full hookups and must have WiFi with streaming capability crowd".....

flybouy
08-10-2021, 10:14 AM
Ok so the shunt itself is a part of the meter. Something else to buy and install. Seems, at least with the whiz-bang electric control systems (like iN-Command), that would be integrated.

Why "intigrate" something that wouldn't be used by perhaps 90%+ of the purchasers? That's why it's a customer added item, just like a sevond spare tire, a bike rack, etc.