eletric brakes wiring question.

[2310 guy]

I just bought a u-build tandem trailer that needs wiring and a deck. The axles have electric brake. I was wondering if anyone knows how to attach all 8 wires (4 pos and 4 neg) to the 7 pin trailer connector. I was assuming you could attach all 4 pos wires to the brake pin and all 4 neg wire to ground. Attach them in parallel .

I've never done this before for so any advice would be great.

Thanks in advance. K.C.

 

[bobodu]

TECHNICAL INFORMATION AND TECH ARTICLES

Should have everything you need.

 

[Stimw]

The wires shouldn't have polarity. The ones I've worked with were all black coming from the brake coil.
You just hook one wire to trailer frame at each wheel for ground and run the positive wires to one main wire going to the front of the trailer just like you would do hooking up marker lights.

 

[bucmeister]

On another site I visit they had a lengthy discussion about what ended up being the most **** retentive way of wiring brakes. The talk was about how to get the most even balanced brake action. The considered agreement was to run a wire from the plug to a central spot then connecting (this is the **** retentive part) all four magnet wires to the same point with the same length of wires. They said that the way you get the same level of line loss/impedance to all brakes. Actually made sense to me, befitting of my **** retentive perfectionist nature.

 

[2310 guy]

On another site I visit they had a lengthy discussion about what ended up being the most **** retentive way of wiring brakes. The talk was about how to get the most even balanced brake action. The considered agreement was to run a wire from the plug to a central spot then connecting (this is the **** retentive part) all four magnet wires to the same point with the same length of wires. They said that the way you get the same level of line loss/impedance to all brakes. Actually made sense to me, befitting of my **** retentive perfectionist nature.

HAHA sound **** to me.... but makes sense... kinda. The difference in wire length is minimal. I say if your concerned that much about braking power don't go with electric.

Thanks again for all the info everyone.

 

[GT2]

HAHA sound **** to me.... but makes sense... kinda. The difference in wire length is minimal. I say if your concerned that much about braking power don't go with electric.

Not to mention that if your trailer wasent perfectly loaded over the tires, and then there is weight transfer to the front axle, so perfect brake balance is not achievable anyway.

 

[Treemonkey1000]

There is so little difference in the voltage loss across that short of a length a wire that it is not worth worrying about. If you had several amps of current then it starts to add up. Having extra wire to worry about snagging would be my bigger concern.
Advanced Wire Resistance Calculator

 

[bobodu]

I would like to mention that the page I posted contains specific warnings against using the frame for a ground.Anyone who has had lights fail will understand why.

 

[Reg]

Yes, wire them in parallel.
I don't think there is any polarity to worry about, but if the two wires from each magnet have different colors it might be worth wiring them as same color to same color.

Here's a minor tip;
When you have them all connected up get a battery charger that has an ammeter and can put out about 15 amps. The 4 brake magnets should draw about 3 amps each, so when you connect the charger you should see about 12 amps on the meter and hear all 4 HUMMING ! Maybe clunks as they come on.
If you only see 9 or fewer amps... guess what ? Yep, go find the open cicuit one(s).

 

[gemini5362]

.

I would like to mention that the page I posted contains specific warnings against using the frame for a ground.Anyone who has had lights fail will understand why.

I agree with bob using the frame for a ground can cause a lot of problem not the least of which is gound to the automobile unless you run a wire from the 7 pin connector to the trailer frame.

I would just hook all the wires the same color together. I have never noticed where the polarity makes a difference. I am going to suspect that since it is a solenoid it really does not matter. You are just pulling a chunk of steel into a coil all it cares about is having a magnetic field. I dont believe the polarity of that field really matters. I am however sure that if I am wrong there will be a physics discussion to show me where i am wrong.

I would get a metal pull box for each side and make my connections it it. I would also solder all my connections. Trailer lights and brake connections are usually out in the weather,they go through mudholes, vibration etc. Everything you can do to make those connections more secure is better. Also
if you really want to do a great job get something like black flexible pipe and run the wires through that. You can get clamps to clamp that to the frame. and not have to worry about wires getting a bare spot rubbed in them. I realize I have added a lot to the job but doing it while you dont have a deck on it will make it a lot easier and having to find a bare spot in the wire or a loose connection when you have been using the trailer for a year or two will not be as easy.


to give you an idea I had to weld clamps on to my frame to hold wires in place after I had the trailer for about 6 years. I had fixed where the wires came loose and got tired of doing that so decided to fix it right. It would have been a lot easier to weld them on when I replaced the deck than to lay under the trailer and do my welding.


My last piece of a long list of advice is to get a lot of holddowns you can get D rings that either bolt in place or can be welded. I have three on each side as well as one in the middle of the back of the trailer. This is in addition to the three holders that were on the trailer when I bought it. Basically I have 6 places on each side to hook onto. I also have a 5/16 chain hook welded to each corner. You can order hooks with a flat bottom that are made to be welded. Now when I want to tie things down I always have a place to tie to that is a straight shot across the trailer if I need to do that. When I put something big like a tractor or a car on it I just run a short chain down to the chain hook and hook it up to that. It is much faster to hook things up now and I dont worry about is it going to stay on when I tie it down. The D ring in the center on the back of the trailer is great for when I have something like plywood on the trailer. No matter how tight I tie it down from the sides it seems to work its way loose sometimes. Now I use a 4 inch nylon ratcheting tie down that runs the length of the trailer I use the same kind of tie down across the trailer in two places and then run the long one down the length of the trailer and ratchet everything tight. It is much better than the trip where I had 10 sheets of plywood on the trailer coming home at night and when I got home it was not on the trailer any more.