LumberJocks

A Question Totally Unrelated to Woodworking....

  • Advertise with us

« back to Coffee Lounge forum

Forum topic by poopiekat posted 05-17-2012 06:14 PM 1151 views 0 times favorited 9 replies Add to Favorites Watch
View poopiekat's profile

poopiekat

4226 posts in 3202 days


05-17-2012 06:14 PM

Topic tags/keywords: question

Here goes: Are trailer electric brakes OFF when current is applied? Or are they ON when current is applied? I’m adapting my 4-pin 3/4 Ton truck to a 7-pin trailer that has electric brakes. I’ll probably get a brake-buddy, but I’m not sure if I need a relay of some sort. If you’ve been up to your shirtsleeves working on your hubs, maybe you have the right answer. Google has let me down so far, lots of great diagrams, but my question goes unanswered. My brain thinks in terms of air-operated brakes, and I’m just not sure… Oh, BTW, I might haul wood in this trailer :-) Thanks in advance!

-- Einstein: "The intuitive mind is a sacred gift, and the rational mind is a faithful servant. We have created a society that honors the servant and has forgotten the gift." I'm Poopiekat!!


9 replies so far

View eddie's profile

eddie

8443 posts in 2081 days


#1 posted 05-17-2012 06:39 PM

poopiekat will the 4 pin going to the 7 pin cause any problems.the breaks i have dont receive any current till the break pedal is pressed. i know this is no help was just wondering about the adaption.

-- Jesus Is Alright with me

View HawkDriver's profile

HawkDriver

447 posts in 2100 days


#2 posted 05-17-2012 07:22 PM

Poopiekat,
I’m assuming that you are installing a 7-pin receptacle on your truck and that the trailer you will be using already has a 7-Pin installed? Electric brakes do not operate like air brakes. Pressure is only applied when current is applied. To get the most out of your electric brakes I would suggest going with a controller. This will allow you to adjust the gain based on how heavy a load you are pulling. Some models will also allow you to operate the trailer brakes independently from the vehicle brakes with the use of a thumb switch.

Hope this helps

-- Patrick, Helicopters don't fly. They beat the air into submission.

View DrDirt's profile

DrDirt

4169 posts in 3209 days


#3 posted 05-17-2012 08:10 PM

They are off when not powered- so when your brake lights come on – the brakes com on.

However perusing some trailer sites there are (often) safety switches – and a battery on the trailer tongue.

The travel trailer we used had this as well, there is a steel cable (like a 10 speed bicycle brake cable) that attaches to the tow vehicle – it pulls a pin in the event your trailer detached from the car, this would activate the trailer brakes with their on board battery.

However I know a lot of folks that have used various kits to ADD electric brakes to cargo/flatbed trailers, where no such safety back-up is used. – - – which is no less safe than a basic u-haul trailer that has no brakes at all anyway.

Insert Copy/paste:

Safety Features
Most states require that trailers using electric brakes be equipped with a safety circuit, called a breakaway system, designed to apply the brakes should the trailer become disconnected from the tow vehicle. This system consists of a battery mounted on the trailer and a normally closed switch. The contacts of the switch are separated by a piece of non-conductive plastic to which a lanyard is attached. The other end of the lanyard is attached to the tow vehicle.

Should the trailer become detached from the tow vehicle the lanyard is pulled, closing the switch, applying current from the on-board battery to the brakes, stopping the trailer.

-- 'Political correctness is fascism pretending to be manners' ~George Carlin

View poopiekat's profile

poopiekat

4226 posts in 3202 days


#4 posted 05-18-2012 01:24 PM

Thanks, Everyone! Yes, a 4-pin flat on the truck, to a 7-pin round on the trailer. I did find the right adapter for that, but $42, ouch! I think I’ll just leave the e-brakes disconnected, for the time being. My last experience was that the brakes would screech and try to slow down the whole rig before the truck brakes would engage, so on that setup I disabled the brakes of the trailer entirely. Ditto on the breakaway switch, I do indeed have that option, and I’ll have to get a charge in the battery before going on the road. Dr Dirt: your paste says ‘normally closed’ switch…I’m sure the writer meant ‘normally open’, right?
again, Thanks for all the great info!

-- Einstein: "The intuitive mind is a sacred gift, and the rational mind is a faithful servant. We have created a society that honors the servant and has forgotten the gift." I'm Poopiekat!!

View Bertha's profile

Bertha

13003 posts in 2160 days


#5 posted 05-18-2012 01:25 PM

Ford or Chevy, Poopie? :)

-- My dad and I built a 65 chev pick up.I killed trannys in that thing for some reason-Hog

View poopiekat's profile

poopiekat

4226 posts in 3202 days


#6 posted 05-18-2012 01:35 PM

Al, both my Dodge Ram 2500, and my ford Ranger have 4-pin flats. Ooops not entirely true, the Dodge had some weird square plastic socket with pins, which I earlier found an adapter to 4-pin flat in the discount bin at NAPA. I never seen another adapter that might fit, glad I bought it when I did! And now I’ve converted that to 7 pin, with liberal amounts of di-electric grease to keep it all from corroding. My wife caught me looking under the back of her CTS to see what kind of connection was provided there! Heh!! Ahem, were you trying to entice me to start a GM-Ford-Mopar-palooza, Al? LOL

-- Einstein: "The intuitive mind is a sacred gift, and the rational mind is a faithful servant. We have created a society that honors the servant and has forgotten the gift." I'm Poopiekat!!

View Bertha's profile

Bertha

13003 posts in 2160 days


#7 posted 05-18-2012 01:58 PM

I’m a Chevy 2500HD guy, so….yes, I was:)

-- My dad and I built a 65 chev pick up.I killed trannys in that thing for some reason-Hog

View poopiekat's profile

poopiekat

4226 posts in 3202 days


#8 posted 05-18-2012 02:32 PM

*Mission accomplished
002-18
The weight-equalizing hitch is a real bear to lift, and this rig also came with stabilizer/sway bars as well. I actually found a relay for the 12V brake circuit! Good to go, ...er, assuming that the brakes aren’t grabby or ill-mannered.

-- Einstein: "The intuitive mind is a sacred gift, and the rational mind is a faithful servant. We have created a society that honors the servant and has forgotten the gift." I'm Poopiekat!!

View Joe Lyddon's profile

Joe Lyddon

9451 posts in 3519 days


#9 posted 05-18-2012 04:15 PM

Hey Poopie…
Looks good! Glad you got your problem solved!

When I first saw that white connector mount with the Grey sockets on it, I thought to myself…
”I never saw a connector panel like that before!”.
Then it hit me what it was… a Security measure… (to hide from the Police! LOL kidding!)

-- Have Fun! Joe Lyddon - Alta Loma, CA USA - Home: http://www.WoodworkStuff.net ... My Small Gallery: http://www.ncwoodworker.net/pp/showgallery.php?ppuser=1389&cat=500"

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com