01-20-2014, 07:39 AM
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Cheap (timer) vs Quality (proportional) brake controllers
I'm just copying and pasting this here from another forum I help manage for the benefit of everyone here as well. I wrote it with those hauling things other than horses in mind, but IMHO it's even more important for those hauling livestock, so I thought I'd post it up here as well.
I often see threads all over the net where people report difficult (trailer pulls and yanks their tow vehicle), jerky (too much) or soft (too little) brakes, and one of my first questions is "What trailer brake controller do you use". Sometimes the results tell the story.
Many people report their model of brake controller only to discover that their controller is a "Time" based model. PROBLEM.
Myself, and many others who understand these controllers, and their failings, consider timer based electric brake controllers to be dangerous - virtually an accident waiting to happen.
I'll explain why.
Contemplate the following. You're cruising down the interstate at 70 MPH with thousands (or tens of thousands) of pounds of trailer behind you. All is well in the world.
Suddenly, there's an accident on the road in front of you. Cars go everywhere, smoke from locked tires, people smacking into the guardrails, cars spinning everywhere....and you're heading right for it with nowhere to go.
Instinctively, you mash your brake pedal....and the trailer braking reaction begins. Now, you go down one of two paths depending on if your tow vehicle is equipped with a good proportional electric brake controller, or a cheap (and arguably, dangerous) timer based controller:
Proportional Electric Brake Controller: The second you touch the brake pedal the brake controller wakes up. Immediately it senses massive deceleration of your tow vehicle due to the controllers built in inertial sensors. Since it detects rapid (emergency) stopping effort is being called for, it instantly answers the call and provides the same (maximum) braking effort to your trailer. Setup correctly, the trailer will provide the maximum physical braking effort it can provide just short of wheel lockup.
You stop rapidly and safely without becoming involved in the accident yourself. Whew!
Timer Based Electric Brake Controller: Since the setup of a timer based controller is based on maximum braking effort, and time delay to get there, you are very limited in functionality. You can't set the controller for more then the maximum amount of braking effort that provides a "comfortable" amount of braking from the trailer without causing the trailer to drag the tow vehicle uncomfortably hard during normal stops. Most people subsequently adjust the "delay" fairly long so that driving in stop and go traffic doesn't result in herky-jerky braking effort. Some people NEVER get them setup correctly and tend to favour setting the controller to provide very low braking effort in order to avoid herky-jerky or wheel-screeching stops.
What MUST be remembered is the following:
- The "Maximum" brake power you setup will NEVER be exceeded. If you set the controller to provide only 6 Volts (~50% braking effort) to the trailer brakes, the controller will NEVER exceed 50% braking effort unless you manually apply the controller.
- The "Delay" never changes. The controller doesn't care if you're making a gingerly stop in town, or an emergency stop on the interstate - it'll still act according to how you set it up. If you set it to provide a 6 second delay to reach maximum braking effort (which, as per the last setting, may actually only be 50% braking effort at that!), it'll always take 6 seconds to reach the maximum braking effort. Simple math says that at 3 seconds it may only be providing a mere 25% braking effort. You see where I'm going with this?
So, back to our accident scenario.
Your'e cruising along, the accident happens. You mash your brake pedal. What happens next with the timer based brake controller? Very little!
The controller is "Dumb". It has no inertial sensors that allow the controller to be able to see that you are in the midst of a critical emergency stop. It has no idea whatsoever, so it treats this stop as any other - a gentle, ramped application of the trailer brakes....but ONLY to the maximum you set it to!
So, the trailer begins to push you...HARD. You push the brake pedal in your truck harder and harder, but the trailer is only 2 seconds into it's "Ramp" up of the trailer brakes, and the trailer is still only providing perhaps <20% braking effort. A second later, maybe 30%. Did you set the controller for 40% maximum braking effort? Yep, a few second later you reach 40%, and that's it - the trailer brakes won't apply any further, no matter what.
The trailer continues to PUSH...PUSH...and PUSH...providing totally inadequate braking effort...and SMASH..you become part of the accident due to your inability to stop. The trailer just didn't provide enough braking effort since the controller had no idea it was an emergency.
For all the controller cares you were still in stop and go traffic just tapping the brake pedal, not trying to push it through the floor board moments before an impending accident.
Ask yourself...what scenario do you want to be in?
If you have a timer based controller, they are DANGEROUS. Yes, they are better than nothing, but once you understand their failings you understand why they really should be replaced by a proper inertial based controller.
An inertial based controller has "brains" that knows how fast you are trying to stop - a gingerly stop at a stop sign, or an emergency stop on the interstate at high speed, and it acts accordingly. A "timer" controller is dumb - it has no idea what's going on aside from the fact that you're stopping. Set it aggressively and every (attempted) gentle stop at a stop sign is knocking your horses off their feet and nearly locking your trailer wheels. Set it gently to avoid that and that emergency stop someday could result in a wreck with devastating consequences.
Hopefully the example above will help you understand the situation better.
Questions, comments? Discuss below. I'm happy to answer questions.
01-20-2014, 09:12 AM
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Until I came I had never heard if brake controllers - my old trailer in the UK had a mechanical brake that was activated if the trailer and truck became separated, but nothing more. My trailer here has electric brakes but I currently have no brake management system. I have been told about them, and am thinking of getting one fitted.
Does anyone know why they exist here but not there? Is it because trailers in North America are heavier? Is it a regulation thing?
As an observation, but by no means a statistical evidence thing, I never heard great tales of trailers causing crashes in the way you describe but I do not doubt that it happens.
01-20-2014, 09:53 AM
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Wasn't "their" the braking systems from reading many comments sound like surge brakes...works off of the trailer hitch moving tightly against the ball and engaging the braking system?
Not sure about that...PrivatePilot is that accurate a description simplified?
As for here in the USA...there are laws stating that vehicles over certain weights must have brakes on "xyz" number of axles.
Surge brakes at one time were popular here but most trailer manufacturers went to electric brakes I believe because they work better and can be adjusted for how hard that brake is applied.
You don't want to drag your empty trailer down the road but you sure need more braking action applied if you are fully loaded with 4 horses on board plus their feed and equipment.
Aside from the fact it takes a great strain off of the tow vehicles braking system which is made to stop the weight of that vehicle and a little more adequately, not a few thousand pounds of extra pushing it down the road.
A trailer outfitted with a brake controller properly adjusted and working can actually stop the entire truck & trailer with never putting your foot on the actual brake pedal just turning the dial or pushing the activation bar...
In times of dangerous road conditions, accident happening, sudden stop...you truly appreciate having those trailer brakes to help you stay true and straight in your lane, not veering off or being pushed sideways down the road out of control.
You are very lucky you have never witnessed the carnage of some of those horse trailer accidents...they can be horrific!
Everyone is so concerned with "Can my vehicle tow this horse trailer"...
Most vehicles can tow forward great weights...
It is the safe stopping ability and power needed of those vehicles that people forget to calculate in their purchase of a tow vehicle. Adding trailer brakes to the equation just makes it all much safer and easier for you, the driver.
The other thing I truly like about the electric brakes is if you should uncouple from your tow vehicle going down the road...there is a thin line that is the "emergency" activation of your brakes that is supposed to slow your trailer down in a straight line to a stop...never needed to use it, hope I never will...but another good reason to have a properly working braking system on any trailer of any type on the road.
Your life, your horses and those around you sharing the road rely on you being in complete control of your rig at all times under all conditions good or bad.
01-20-2014, 10:37 AM
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In North America surge brakes are really only common on boat trailers, mainly because electric brakes do not survive immersion in water very well – aside from that they are fairly uncommon on most trailers with the exception of a few small pop-up tent trailers that I've seen them equipped with in recent years for simplicities sake – people can tow them with an extremely small car without the hassle of wiring in a brake controller.
Although it varies a little bit from area to area, typically the requirement for brakes versus no brakes on a trailer is around 3000 gross pounds – which pretty much encompasses any sized horse trailer with at least one horse in it, therefore you will find that pretty much any horse trailer on the market comes equipped with trailer brakes, same be said for any sort of utilitarian, recreational, or other style trailer that would exceed that weight loaded. The better manufacturers of even smaller trailers that may not technically exceed the 3000 pound limit (but would come close) often equipped their trailers with brakes for the safety margin and as a selling feature.
As for the differences in trailer braking overseas, it's been my observation that outside of North America surge brakes are still almost overwhelmingly the most common type of trailer braking system across all types of trailers, although as mentioned electric has many advantages, as well as some disadvantages. Just because a trailer doesn't have electric brakes, doesn't mean that it doesn't have brakes at all – if you look closely you may find a surge brake style system.
Also, many drivers in the European areas tend to just be generally better drivers – driver education is far superior to almost anything that we have here in North America, turning out higher-quality and safer drivers on the roads as a result, so the requirements might be laxer. It's the main reason that you see European vehicles rated to tow so much higher weights then what you would see an identical vehicle here in North America rated to tow. Poorer drivers = more risk of accidents = liability = manufacturers putting lower ratings to CYA. ;)
01-20-2014, 12:08 PM
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Interesting to read! I really had no idea about the differences. I'm guessing/hoping that my ford f150 has the Proportional Electric Brake Controller? It has the built in break controller so I really have no idea on his specs, I just know how to adjust it and to slide the thing to apply the breaks manually. When shopping for break controllers, do they usually say in description what they are? What's something people should really look for in the description to know they're buying a good aftermarket controller?
01-21-2014, 01:10 PM
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The integrated brake controllers in vehicles so equipped are even better yet as they are usually integrated into the tow vehicles braking system, receiving even more data on what the vehicle is doing and behaving accordingly.
Arguably, they are the "best of the best" so far as brake controllers go.
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