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Trailer Brake Controller - factory installed?

Discussion in 'Cybertruck' started by Capt Starbucks, Mar 6, 2020.

  1. Capt Starbucks

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    I know none of us know anything at this point, but I sure hope they offer a factory installed trailer brake controller that is capable of knowing what trailer you are towing.
     
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  2. dazedNconfuzed

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    Musk tweeted: "Yes, will also show real-time changes to max acceleration, braking, cornering, speed on gradient & range, latter factoring in route elevation changes & cargo or tow mass & drag impact"

    Seems it will automatically detect all relevant information about what it's towing.
     
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  3. Puddles

    Puddles Member

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    For a vehicle this size, isn’t a surge brake more than adequate? I don’t see a need to overengineer this. A.k.a. “Solution desperately seeking problem”
     
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  4. Capt Starbucks

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    By trailer brake controller, I'm referring to controlling the brakes on what is behind the truck. No matter if Cybertruck is the best rig on the planet, it STILL will need to tell the trailer when to apply it's own trailer brakes.

    Surge brakes are not legal in Canada for good reason on trailers over what, 4k? My 12,000 boat/trailer has 4 wheels and 4 disc brakes. They are electric over hydraulic like most giant boats on trailers. The truck electric brake controller sends a signal to an electric master cylinder on the boat trailer, that converts the electrical signal to hydraulic power via piston, the piston actuates hydraulic power to the trailers hydraulic brakes. Very common for anything large that is dunked repeatedly in saltwater. Electric brakes such as on a travel trailer would fail soon after the first time they were dunked.

    There are aftermarket trailer brake controllers obvi, but being brand new CT, just want to make sure this new truck is usable for my purposes. Most modern brake controllers know the exact resistance of whatever trailer you hook up, so if you tow multiple trailers, it knows what setting to default to when it senses that trailer (by resistance differences unique to each trailer I'm sure).
     
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  5. Coaly

    Coaly Member

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    No, electric brakes are on most trailers. Surge brakes have a hydraulic master cylinder on the tongue that moves with a linkage to apply brakes when the inertia of the trailer surges ahead, applying trailer brakes. That system won’t work with load equalizing bars. You need electric to apply when the trailer starts to fishtail from being overtaken by a larger vehicle or to apply downhill without using the tow vehicle brake hard enough to apply trailer brakes. Electric brake controllers do not put out a full 12 volts until needed and are adjustable for angle mounted under dash and sensitivity. There is a pendulum type affair inside that breaks a beam of light applying trailer brakes automatically. There is also a manual slide switch within reach of the driver. Some trailers also use brakes for sway control with a pendulum on trailer tongue to apply left or right brake to prevent sway.

    The power supply for a brake control is normally auto-reset circuit breaker controlled in case a magnet wears through, windings short on drum, and a fuse would blow, incapacitating brakes. A resettable breaker resets giving you at least intermittent trailer brakes.

    Trailers with brakes also require a 12 volt battery charge wire for trailer battery charging for breakaway brake switch. There’s a lot of engineering that goes into a trailer brake.

    Load equalizing bars are another issue to overcome without a frame to lift the rear axle, and transmit the weight to the front wheels. The exoskeleton would have to do it without flex. Tremendous torque on a hitch torque tube, pulling downward on the front of hitch mounts.
     
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  6. Dithermaster

    Dithermaster Member

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    It would be nice if the braking controller used pure regen up until a certain amount of brake pedal is pushed. It would be ideal for recapturing all the kinetic energy instead of using the trailer's friction brakes. Of course for deeper pedal movements you'd want the trailer to do braking too.
     
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  7. Capt Starbucks

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    I agree. That's a great idea. Might as well get back as much power as we can. It should have a way of overriding that feature if it indeed comes to fruition. Steep mountainous highways in the rain out here in the west with 12k behind you would require the trailer brakes are on point the moment you apply truck brakes. You don't want the beast behind you pushing too much or you'll jackknife. I'm all for new technology, but this Cybertruck better be all that. My current F-250 has a scale weight of 8,200 lbs with me and half a tank of fuel. I imagine tow rig weight isn't as important as people think but I don't know. I'm only saying that due to the fact that semi trucks pull many times the weight of the tow vehicle. I only bumper pull so it's different than a semi.
     
  8. GNFO

    GNFO Member

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    I have a 3rd party brake controller for my MX, and I've always wondered why couldn't the car handle that function itself. It has accelerometers just like the controller, obviously already has the proper wiring, and given everything else the car is capable of, it seems like a relatively simple thing to control the varying braking signal to the trailer.

    Not only do I feel like the Cybertruck should be able to do this, but Tesla could probably even "retrofit" the capability in the Model Xs with the right rerouting plug to fit into the existing brake controller jack and a software update.
     
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  9. CyberGus

    CyberGus Not Just a Member

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    Some have noted the apparent dual cameras in the rear of the Cybertruck prototype. One plausible reason for high-acuity imaging in the rear is to closely monitor a towed vehicle. The internal AI could then maximize regenerative braking safely.
     
  10. MP3Mike

    MP3Mike Well-Known Member

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    And here I thought those cameras were just so that AP could backup the Cybertruck, lower the rear to under the trailer tongue, position the ball, and then raise the suspension to complete the hookup while you just sit and monitor things.
     
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  11. CyberGus

    CyberGus Not Just a Member

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    I welcome the new “hook-up” mode ;)
     
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  12. Dithermaster

    Dithermaster Member

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    Tesla should build in the braking controller for the simple reason that it can maximize regen braking for most braking events and only kick in the trailer friction brakes when really needed. Furthermore, using the sensors on the vehicle it can "learn" what voltage (on the braking pin) equates to how much braking force, and modulate the signal appropriately.
     
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  13. coleAK

    coleAK Member

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    No. For pulling anything over 3-5k lbs (even with a 1 ton) a trailer with brake controller is vastly superior to surge brakes.
     
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  14. coleAK

    coleAK Member

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    Have you ever towed with a brake controller? Probably not because they don’t work that way. I tow a ~7k lb camper 8-10k miles a summer. There is no way to know for the truck to know what the trailer is. However some brake controllers are highly adjustable and “smart”. With Regen brakes Tesla will have to have a built in one.

    Considering most 1/2 ton trucks and SUVs now come with Standard or optional built in trailer brake controllers for Tesla not to have one would be sub-standard.
     
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  15. coleAK

    coleAK Member

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    My current 5 year old Redarc controller pretty much does this.
     
  16. ngng

    ngng Member

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    actually that's not 100% true. the newer ford trucks can detect which trailer is being towed. my EE buddy explained it to me at some point, something about the truck sensing the resistance of the attached trailer wiring.
     
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  17. ngng

    ngng Member

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    i used to tow with a tekonsha prodigy on my old 7.3l f250. great controller. but, when comparing it to the factory ford brake controller it the prodigy was not even worth mentioning. the real time feedback for the active sway control just so impressive.
     
  18. TessP100D

    TessP100D Member

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    I agree 100%
     
  19. coleAK

    coleAK Member

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    No way to sense the resistance in any way. 7pin Trailer connectors have wiring for the lights, 12v, and for the Trailer Brakes (see below). Now every controller I’ve had have various adjustments from maximum brake force and delays. Pretty much you set the controller to your trailer. And even then it’s common to need to adjust on the fly, like personally at slow speeds (like around town and through long stretches of slow construction zones) I like to turn the brake force way down.
    upload_2020-8-2_21-57-4.png
     

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  20. ngng

    ngng Member

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    i was curious how it actually works so I asked him again and he said "capacitance". then he signed off ;)

    re: adjusting around town. did you set your brake output level? once i've done that, I never touch it. it's something like drive 15mph and fully engage the trailer brakes. if they lock up, reduce the output. rinse and repeat until they don't lock up. of course, this is different per trailer.

    I don't recall the OEM controller have a delay setting, just max output
     

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