Trailer Break Battery

[bigtiller]

How do you tell if it can hold a large enough charge long enough to do its job properly? Or do you just buy a new one every year?

I am finished using my trailer for the year so I took the battery out charged it with a maintainer for a few days and set it on the shelf ready for next year.

 

[jeffsw6]

I personally don't like to let batteries sit all winter. I don't think you should have any reason to buy a new one each year. If you do, it's time to change how you maintain them!

 

[Diamondpilot]

How do you tell if it can hold a large enough charge long enough to do its job properly? Or do you just buy a new one every year?

I am finished using my trailer for the year so I took the battery out charged it with a maintainer for a few days and set it on the shelf ready for next year.

The law is in Indiana, as in most states, that it must hold the brakes for 15 minutes. If you want to test it, hook it up to the truck and drive it around for 10 minutes to top the battery off. This is assuming the charging system on your trailer and truck are properly wired. Park the trailer on dirt or gravel and pull the brake-away and set your stop watch for 15 minutes. When time has expired start the truck and ease forward. It should drag all the wheels that have brakes on them. My trailer for example only has them on the rear axle. If not, the battery is not up to snuff.

This is essentially how the dot checks them. You drive it to the check station, (the 10 minutes I said before), pull the brake-away, wait 15 mins, and see what happens.

My battery has not been checked in 1.5 years but is 8 years old and was still good to go then. They last a long time.

Chris

 

[George2615]

On my trailers I removed the small trailer brake battery. Instead I wired mine to a regular full size deep cycle battery I put in that also powers my winch and electric / hydraulic tilt bed trailer.
Before, With the smaller trailer battery I used to get 2-3 years then had to replace.

 

[Iplayfarmer]

...My battery has not been checked in 1.5 years but is 8 years old and was still good to go then. They last a long time.

Chris

Chris is cheating because he pulls his trailers A LOT compared to many of us. If you're like me and only pull your trailer a few hundred miles a year it's probably a good idea to top off your battery regularly with a charger. Letting a lead acid battery sit without a full charge will kill them fast.

 

[bigtiller]

I was kind of hoping there was a 3 dollar Harbor Freight gizmo that would take an electrical measurement straight off the battery and tell me what I want to know.

 

[Iplayfarmer]

I was kind of hoping there was a 3 dollar Harbor Freight gizmo that would take an electrical measurement straight off the battery and tell me what I want to know.

It's more than $5, but this is a typical battery tester... Battery Load Tester - 100 Amp, 6v/12v

You have to interpret the results based on the size of your battery, but it will tell you how much juice your battery will store. I have one of these (different brand) that I got at a yard sale, and I love it.

 

[JB4310]

Uh, I better check mine, since I've never checked it, even when I bought it :ashamed:

15 minutes seems silly though, since it only has to hold for 10 seconds in a typical break away.

I figure if it reads 12 volts, it's gonna work. But I never even checked mine to see if there is 12 volts.

If they really wanted to make them foolproof, do it like air brakes, no power, no go.

JB

 

[jeffsw6]

I figure if it reads 12 volts, it's gonna work. But I never even checked mine to see if there is 12 volts.

If you just put a volt meter on a battery it may show 12V when that meter is drawing a fraction of an amp, but once you put a load on it the voltage may drop dramatically. It's kinda like the TV remote, if you don't have spare AAAs around the house you just leave it alone for a few minutes and then you can probably switch channels again, but do much surfing and it runs out.

That's why the battery tester linked above puts a load on the battery.

 

[tcartwri]

I've had the road side test done by the dot/mot and it was only for 30 seconds or so. You pull the deadman switch, and then try to pull the trailer forward while the dude watches. The battery and wiring get friggin hot in a hurry, lol.

 

[bigtiller]

It's more than $5, but this is a typical battery tester... Battery Load Tester - 100 Amp, 6v/12v

You have to interpret the results based on the size of your battery, but it will tell you how much juice your battery will store. I have one of these (different brand) that I got at a yard sale, and I love it.

I have a load tester similar to that but I seldom have a chance to use it any more. I had no idea I could use it on such a small battery. I'll have to read up on it tomorrow.

 

[Diamondpilot]

Chris is cheating because he pulls his trailers A LOT compared to many of us. If you're like me and only pull your trailer a few hundred miles a year it's probably a good idea to top off your battery regularly with a charger. Letting a lead acid battery sit without a full charge will kill them fast.

This is true. Its been 2 weeks since I had my 18' car hauler out of the barn and seems like forever. Its next job is to go get some siding for a barn extension.

Chris

 

[slowzuki]

15 minutes? So say the brakes full on are 20 amp draw, so a 5 amp-hour battery? I'm sure the little ones we use here won't get that.

 

[TRR]

You drive it to the check station, (the 10 minutes I said before), pull the brake-away, wait 15 mins, and see what happens.

Be sure you disconnect your brake controller. Mine has a warning that the brake controller could be damaged by pulling the brake-away switch while connected to the truck.

 

[bigtiller]

15 minutes?
30 seconds?
wire gets hot?
controller may get damaged?
20 amps from a 5 amp battery?

Is there some conflicting information here or am I having a problem processing it all?

 

[Diamondpilot]

15 minutes?
30 seconds?
wire gets hot?
controller may get damaged?
20 amps from a 5 amp battery?

Is there some conflicting information here or am I having a problem processing it all?

I am just telling you what the law is. Here in Indiana, like most states its 15 Minutes. I guess they figure by that time help would be on the way to secure the trailer in a worst case situation.

I have done this tons of times and never remember excess heat in the battery or wiring.

Its a good idea though to pull the plug from the truck. It makes sense because the trailer would be separated from the truck anyway if needed.

Chris

 

[MikeD74T]

...:ashamed:15 minutes seems silly though, since it only has to hold for 10 seconds in a typical break away... JB

A few seconds would allow the trailer to stop but suppose you were going down a hill & disconnected. Would you like to be backing up only to realize the brakes had released & the trailer was now rolling toward you ??? I wouldn't assume the breakaway actuated before the chains fail, although I'd hope it did. MikeD74T

 

[jwstewar]

Last time I took the camper out, I routed the breakaway wire a little differently than I normally do because it seemed pretty long. Well, apparently I took out too much slack. I pulled up through the yard to make a left turn to the driveway and all of sudden the truck stopped and started grunting. The pin had pulled out and locked all 4 tires on the trailer. Brake controller (Tekonsha Prodigy) read error or something, don't remember exactly. Plugged the switch back in and was good to go. Trailer tires slid probably 7 - 8 feet in the wet grass.

BTW, this is out 36' Jayco that weighs 8k from the factory towing it with my '99 Silverado 1500.

 

[JB4310]

A few seconds would allow the trailer to stop but suppose you were going down a hill & disconnected. Would you like to be backing up only to realize the brakes had released & the trailer was now rolling toward you ??? I wouldn't assume the breakaway actuated before the chains fail, although I'd hope it did. MikeD74T

I hear ya, But I'm thinking that initial 60 to 0 MPH part. I agree on a steep enough hill bad things could happen, especially with a heavy trailer, even with the tongue on the ground.

JB

 

[tcartwri]

15 minutes?
30 seconds?
wire gets hot?
controller may get damaged?
20 amps from a 5 amp battery?

Is there some conflicting information here or am I having a problem processing it all?

Triple axle trailer, with brakes on each, draws a considerable amount of current. The terminals on the battery get hot enough to cause burns. Ask me how I know. :laughing:

A 5 A/hr battery will most definitely provide 20A of instant current.