two 12 volt battery configuration - serial or parallel?

jrand3

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I want to ensure I have my batteries connected correctly. The unit is a 2021 Flagstaff Super Lite 26FKBS, with 2 12volt batteries. Should they be connected in parallel or serially? The diagram inside the battery housing shows parallel, yet when I connect it that way there seems to be no power to the inside of the unit, just to the power jack. Both batteries are new. Thanks.
 
Almost all (maybe all) RV have 12 volt systems (not 24), so parallel is the correct configuration. It sounds like your battery disconnect may be activated or faulty. Some items such as CO monitors and power jacks bypass the battery shut off.
 
parallel for 12v

check that your batteries are connected correctly to positive/negative cables going into trailer
test ... when you use the jack is the up/down buttons now reversed?
if you get them wrong you can blow the converter's REVERSE fuses


also check if you have a battery disconnect switch ... make sure it is ON

last look for 12v circuit breakers near the battery ... some have tint reset buttons on the sides
 
When hooked in parallel one lead to the rv is connected to one battery. The negative to the other one. Not both on one.

Likely the disconnect is turned off.
 
I want to ensure I have my batteries connected correctly. The unit is a 2021 Flagstaff Super Lite 26FKBS, with 2 12volt batteries. Should they be connected in parallel or serially? The diagram inside the battery housing shows parallel, yet when I connect it that way there seems to be no power to the inside of the unit, just to the power jack. Both batteries are new. Thanks.

Parallel
Parallel-Connection.png
 
I want to ensure I have my batteries connected correctly. The unit is a 2021 Flagstaff Super Lite 26FKBS, with 2 12volt batteries. Should they be connected in parallel or serially? The diagram inside the battery housing shows parallel, yet when I connect it that way there seems to be no power to the inside of the unit, just to the power jack. Both batteries are new. Thanks.
Everyone has posted the correct answer.
I suggest that you Google "the 12 Volt Side of Life". It's a good primer on the two different RV electrical systems.
 
Thank you everyone. I have ensured that the battery disconnect is in the "connect" position, and the batteries are/were in parallel. I will check for a circuit breaker near the battery. Will also check fuses in the trailer. It seems very possible that the disconnect switch has gone bad for some reason.
 
using a multimeter or test lamp will tell you if switch or breakers passing12v
makes things easy once you get the hang of where to put probes

there is a multimeter for every budget
and tons of videos on youtube

search google ... video how to check battery disconnect with a multimeter


replace underlined words for other things that need checking
 
parallel for 12v
check that your batteries are connected correctly to positive/negative cables going into trailer
test ... when you use the jack is the up/down buttons now reversed?
if you get them wrong you can blow the converter's REVERSE fuses
Been there, done that. IF you blew the reverse fuses (2 40a fuses between circuit breakers and fuses in our TT) then chances are that other fuses are blown as well. I had to replace the 5a fuse in my radio/dvd/cd player in the trailer; as well as 2 or 3 fuses in my tow vehicle when I accidentally reversed pos and neg when hooking up (I pull my battery). I didn't notice until I went to push slide out and 40a fuses blew. I hadn't noticed that the jack and stabilizers were running backwards.
 
I want to ensure I have my batteries connected correctly. The unit is a 2021 Flagstaff Super Lite 26FKBS, with 2 12volt batteries. Should they be connected in parallel or serially? The diagram inside the battery housing shows parallel, yet when I connect it that way there seems to be no power to the inside of the unit, just to the power jack. Both batteries are new. Thanks.
Parallel is best. Provided same voltage, but more amp hours. Check to see if your battery disconnect is switched on.
 
I want to ensure I have my batteries connected correctly. The unit is a 2021 Flagstaff Super Lite 26FKBS, with 2 12volt batteries. Should they be connected in parallel or serially? The diagram inside the battery housing shows parallel, yet when I connect it that way there seems to be no power to the inside of the unit, just to the power jack. Both batteries are new. Thanks.
Just so you know, when you hook them up parallel you will get 12v out of the battery pack. If you hook them up in series, you'll get 24v which you do not want
 
I have a 25FKBS and the battery disconect is on the driver side under the propain tank and its hard to see.
 

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