break-away battery charger??

[PetesonM]

I am rewiring my 16 foot car hauler trailer and am wondering about the break-away wiring. In particular do I need a charger of some sort. It did not come with one just a battery and a switch. I am guessing that I can just hook the acc (12v hot line) to the battery and charge it that way. I can always just unhook the trailer plug when I get to where I am going to save the vehicle batteries. Any opinions.



If I need one where is a good place to get it cheap. I actually need a new switch and battery as well.

 

[klenger]

One solution I've heard of is the use the break light power or backup light power (can't remember which) to recharge the battery. It should come on often enough to keep the battery topped off.

 

[chrleb1]

There is a constant 12 + in the trailer wiring. That wire is for items that need constant power. It is a good idea to have it connected to the battery at all times. It will just equalize with your regular batteries.

 

[JDubien]

Check with your supplier, some batteries can not handle 12v all the time. When I bought my breakaway kit, they offered two kits 1)a disposable battery and a switch 2)a charger, a battery and a switch. They told me the disposable battery would last a couple years and to make sure not to hook it up to a 12v constant as it would quickly damage the battery. Just my . 02 worth

 

[jelag]

I have thrown away all of the dry cell batteries on my trailers... . I now use small wet cells, from Wal Mart, (motorcycle batteries) that 3x's the amp hour rating at pennies on the dollar...



On a DOT installation this is how it is done... ...



I run a electrical panel on all my trailers... its a 7 pin black box like what is used on a semi... . and wire in 12V+ , 12V-, LT, RT, Tail, Brakes, and backup... .



I run a fused wire from the 12V+ to my wet cell, so it can be charged... from the wet cell 12V battery I run a wire to my brake away switch and back to the black box and to the connection for the brakes... so connected to this terminal is the wire from the trailer connector that turns on the brakes, the 12V+ hot lead from the brake away switch when its pulled, and the connection to the brakes... . in some cases with electric brakes thats to the axles... in other cases its to the 12V Pump for the power disc brakes... .



When the brake controller is applied in the truck power flows to the brakes, and if the trailer brakes away, the brake away switch is now ON and full battery voltage is applied to lock the brakes...



All lights are gounded to the frame and the 12V- from the trailer plug goes to the black box, to the 12V- on the wet cell battery and than on to the frame... .



The wet cell batteries are in small water proof and rock proof holders... and every 2 years we throw them away and put new ones in... ... BTW on the trailers with power disc brakes we use a small garden tractor battery instead of the motorcycle battery to run some lights in the trailers as well..... and to power the brakes if the fuse in the pickup blows that keeps this whole thing charged... .



On my travel trailer, its 2 very large 12V diesel truck batteries..... in parallel...



Hope this helps. .



Hope this helps.....

 

[Loren]

7-wire vs. other trailer plugs

PetersonM,



If your trailer does not have a 7-wire plug, you do not have a charging circuit to your trailer. I learned this the hard way when my son-in-law found that the breakaway system didn’t work on my 6-wire flatbed trailer.



It turned out that the trailer was several years old by then and the battery had gone dead. I had never charged it, thinking that it would be charged when I towed the trailer. Wrong!



I replaced the battery. Now I charge the new battery every several months. It isn’t worth the effort to me to install a charging system.



Good luck,

Loren

 

[GAmes]

A six wire plug has a constant hot pin. On mine it is the center one, which I believe is standard.

 

[JFaughn]

Mount one of the small battery maitainer solar pannels on the trailer , about 3" by 8" should be large enough to keep it charged and never over charged , just check the water [ distilled ]twice a yr.

 

[Nate]

I've never actually used that breakaway setup on my trailer. I cut the cable with a grinder by accident when I was doing some work on the trailer and never bothered to fix it.

 

[jnelson]

Mount one of the small battery maitainer solar pannels on the trailer , about 3" by 8" should be large enough to keep it charged and never over charged , just check the water [ distilled ]twice a yr.

Ive replaced my battery twice in 6 years. Works great.

 

[R C Cola]

Breakaway

Nate... . If the DOT ever checks you out closely you will be written up for a safety violation. All states require the breakaway switch operational. 4 yrs. now and mine has not been checked yet. But I hear of it often. They pull the pin and the trailer tires are supposed to drag. R C

 

[Loren]

GAmes is correct. A 6-wire connection is supposed to include a hot wire which would be used to charge the trailer's battery.



Apparently my flatbed didn't get wired correctly.



Thanks, GAmes, for the info. Maybe I'll get around to adding a wire to my breakaway battery someday.



Loren

 

[Nate]

Hmm... I didn't know that. I've pulled a number of trailers and this is the first one I've had this connector on it. I just use the safety chains. Even the guy at the trailer place said not to bother with it... it's just there because they have to put it on per DOT.



I may have to repair it then.

Nate... . If the DOT ever checks you out closely you will be written up for a safety violation. All states require the breakaway switch operational. 4 yrs. now and mine has not been checked yet. But I hear of it often. They pull the pin and the trailer tires are supposed to drag. R C