Thermal Circuit Breakers Question - 2408T

C317414

Senior Member
Joined
Dec 24, 2012
Messages
540
I just got a 2408T and replaced the batteries. I noticed that my trailer has two thermal circuit breakers connected directly to a positive battery post. These are in addition to the two circuit breakers in the battery/pump box that most Hi-Lo trailers seem to have.

The breakers are connected to each other in parallel with small buss bars. They are rated at 25A each. There is a wire hooked up to the breakers and another wire from the same wire bundle hooked up directly to the negative battery post. The wiring is part of a factory wire bundle; in other words, it is not something added later.

I have two questions:

1- Does anybody know what these breakers/wires are for?

2- Does anybody know why would one have two thermal breakers hooked up in parallel?

Thanks,

Raul
 
Normally one of the breakers is for the trailer 12 volt electrical system and the other is for the hydraulic lift pump. I have not seen any with the dual breaker/bus bar setup.
 
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Exactly, I do have the two CBs that you mention and they are mounted on the wall of the pump/battery box. These other two are in addition to the two regular CBs. Also, putting two CBs in parallel is not a good practice. This is why it is puzzling.

Raul
 
Perhaps if you post a picture someone might have an answer for you.

Yep, I've been meaning to do that. Unfortunately It's dark when I leave for work and dark when I get home. :( I'll try to take a picture this weekend.

Thanks,

Raul
 
circuit breakers

these breakers protect the trailer wiring from a overload there are 2 because 50 amp breakers are harder to come by
 
these breakers protect the trailer wiring from a overload there are 2 because 50 amp breakers are harder to come by

I understand the function of circuit breakers, What I asked specifically is what circuits are these breakers protecting and why did Hi-Lo employ the bad practice of connecting circuit breakers in parallel.

As I mentioned before, my trailer has the two breakers that virtually every other hi-lo has installed on the battery box. These breakers power the buses that supply power to a number of individual circuits. The thermal breakers that I am referring to are connected directly to a battery post and have wires that enter the main wire bundle and are not connected to the main buses. It appears that the intent is to protect a high current device. I'd like to know which one.

Incidentally, connecting two breakers in parallel is a bad practice. In theory the rating CBs connected in this way will add up. In my case two 25A CBs in parallel will make a 50A CB. In reality this is not what will happen. The resistance of each CB will be slightly different than the other. Current will take the path of least resistance. This will cause an overload that is less than that required to trip a 50A breaker to trip the breaker with less resistance. The other breaker will then get overloaded and will also trip. In other words, I will not get 50A of protection; I will get somewhere between 25A and 50A.

The real solution is to install a breaker of the required capacity. Incidentally, 50A thermal breakers are readily available. I've used these on a couple of installations on my boat: 285-Series Thermal Circuit Breaker Surface Mount—Blue Sea Systems .

Raul
 
Do you have any options like an inverter, which was not an option from HiLo, or built in generator that would draw a high current? I just can't think of what there would be to require extra breakers like that let alone being a part of the wiring harness. I have only seen the two breakers that are common to most all HiLo trailers and the main battery cable feeds to them.
 
Do you have any options like an inverter, which was not an option from HiLo, or built in generator that would draw a high current? I just can't think of what there would be to require extra breakers like that let alone being a part of the wiring harness. I have only seen the two breakers that are common to most all HiLo trailers and the main battery cable feeds to them.

Good question... I don't have an inverter or generator. It standard 2408T with the tip-out.

This weekend I plan on taking some photos of the breakers and I'll post them here. Also, I may disconnect them, turn on items one by one, energize the tip-out winch, etc, to see if there is anything that does not work.

Raul
 
The tip-out winch would be my next guess, but I can't imagine why it would need anything that heavy to protect it. Do you have the manual, because it should show something in the twelve volt schematic? My wife's cousin has a 2409T. I should ask him if he has anything like that.
 
The tip-out winch would be my next guess, but I can't imagine why it would need anything that heavy to protect it. Do you have the manual, because it should show something in the twelve volt schematic? My wife's cousin has a 2409T. I should ask him if he has anything like that.

I don't have the manual and the downloads on this site are not too clear. The dealer called me a couple of days ago to tell me that he was mailing me a package that the previous owner dropped off. Included in it are the manual, DVD, and a few other items.

Raul
 
It's good to have those manuals. Usually there is a manual for every appliance, the LP leak detector, the toilet, the tires, and a couple other things. I keep all of them in an accordion folder under the seat so they are within quick reach.
 
It's good to have those manuals. Usually there is a manual for every appliance, the LP leak detector, the toilet, the tires, and a couple other things. I keep all of them in an accordion folder under the seat so they are within quick reach.

I definitely agree. On my boat I have a binder with the manuals for all the appliances, accessories, and electronics. It's come in handy a few times.

If I don't get the appliance manuals in the package from the dealer I'm going to download them from each manufacturer's site.

Raul
 
My HiLo also has these two circuits breakers attached to the positive post on the battery. They are not shown on the wiring drawings. I do think they are factory installed. Will look at mine when the weather clears and get back here what circuits they protect.
 
I was able to raise my top today to check on the two circuit breakers and they do power the tipout motor. The tipout is very heavy so the motor must pull quite a bit of amps. The tipout power does not go thru the master switch.
 
I was able to raise my top today to check on the two circuit breakers and they do power the tipout motor. The tipout is very heavy so the motor must pull quite a bit of amps. The tipout power does not go thru the master switch.

LOL... I did the same thing today and arrived at the same conclusion. Attached is a photo showing the two circuit breakers attached to a battery post.
 

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It looks like these thermal circuit breakers were part of a kit provided to Hi-Lo by the tip-out winch manufacturer, Carefree. The same winch is also used as a lift for some pop-up trailers.

The winch owners manual calls for a 50A CB and shows two CBs connected in parallel:
http://www.carefreeofcolorado.com/docs/tech/P3010402AV P55000 Folding Camper Winch.pdf

I think that I'm going to get a 50A thermal CB and replace the two 25 A ones.

Raul
 

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