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12V circuit breakers in series?

happy2rv
Explorer
Explorer
I was putting a battery disconnect on my trailer this afternoon and noticed this:


Click For Full-Size Image

I'm not sure what the point of having two circuit breakers in series like this is, especially since the first one connected to the battery (the one at the bottom of the photo) appears to be shorted out. They appear to be the same size breakers. :h

This came from the factory like this unless the dealer did something before delivery. I'm the original owner and it hasn't been in the shop for any type of electrical work since I've owned it. Am I missing something?
2018 Forrest River Salem Hemisphere 282RK - 2017 RAM 1500 TV

Previous RVs and TOADS
2004 Fleetwood Bounder 32W on WH W20
2000 Four Winds 5000 21RB
1986 27' Allegro
TOADS
2005 Ford Ranger XLT 2WD
2004 Suzuki Aerio
1988 Chevrolet Sprint
18 REPLIES 18

happy2rv
Explorer
Explorer
BB_TX wrote:
Are you certain it is not the larger red wire (on the post with the red jumper and smaller white wire) that goes to the battery?
Those breakers should not be in series. Battery should go to both and then each one feed itโ€™s own circuits.


I will double check, but I'm fairly sure the battery the large red wire on the bottom post in the picture. I'm almost certain the large red wire on bottom post of the upper breaker is the main load center inside the trailer.

BB_TX wrote:
Curious why you think the one is โ€œshorted outโ€. If the breakers are good you will have +12 vdc on both posts at all times except when they trip.


If you look at the full size picture, it's clearer. The ring terminal on the upper post of the bottom breaker is touching the bottom post.
2018 Forrest River Salem Hemisphere 282RK - 2017 RAM 1500 TV

Previous RVs and TOADS
2004 Fleetwood Bounder 32W on WH W20
2000 Four Winds 5000 21RB
1986 27' Allegro
TOADS
2005 Ford Ranger XLT 2WD
2004 Suzuki Aerio
1988 Chevrolet Sprint

BFL13
Explorer II
Explorer II
Not in series. Looks ok except the mystery white wire in with the reds at the lower terminal of the upper CB. White is usually neg.
1. 1991 Oakland 28DB Class C
on Ford E350-460-7.5 Gas EFI
Photo in Profile
2. 1991 Bighorn 9.5ft Truck Camper on 2003 Chev 2500HD 6.0 Gas
See Profile for Electronic set-ups for 1. and 2.

DrewE
Explorer II
Explorer II
I'd guess they are not the same current rating. The first one is the main one, and there are two higher current circuits connected to its output (via the lower lug of the upper breaker). The second one presumably has a lower rating and is for some other stuff.

It may not be the cleanest way of doing things, but it's not entirely senseless in my estimation.

BB_TX
Nomad
Nomad
Are you certain it is not the larger red wire (on the post with the red jumper and smaller white wire) that goes to the battery?
Those breakers should not be in series. Battery should go to both and then each one feed itโ€™s own circuits.
Curious why you think the one is โ€œshorted outโ€. If the breakers are good you will have +12 vdc on both posts at all times except when they trip.