Tow break-away switch testing?

[ghamr]

Is there a way and/or is it necessary to test the break-away switch that activates the AS breaks if the camper comes loose from the TV.
Later: Just read some of the posts below & seems my questions are answered.......

[rmkrum]

If you want to test breakaway, you absolutely MUST disconnect the umbilical to protect your brake control from reverse voltage.

On item two, if you pull it, yes, the brakes will lock, but only as long as your batteries have power. The brakes will run down the batteries rather quickly. Breakaway is an emergency switch that locks the AS brakes full on when it's pulled.

If you are looking for theft protection, run a nice heavy chain or cable lock between dual wheels, get a coupler lock, lock the safety chains to a deadman loop in your driveway, or park the AS indoors. A determined thief can get past all this stuff if they really want the AS. At that point your insurance is your last resort.


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[CBWELL]

Easy to test!! Have trailer hooked up, with electrical connection DISCONECTED.
Pull out the cord with the pin attached. Get in TV and try to drive ahead. Your wheels on the trailer should turn slightly then lock up. If they do no, they need to have the brakes checked and or adjusted. Do not do this test with the electrical connected to your trailer, as you will have an expensive electrical problem. The break away switch is NOT to be used as a parking brake or theft deterrent. Hope this helps!! Good idea to check this fairly often. You must also have good battery power in the trailer for the break away brakes to work.
Don't forget to put the switch back in before trying to drive away after testing!!

[mojo]

FWIW, I inadvertently pulled my break away switch hopping over the hitch while the umbilical was plugged in and nothing got fried on the truck or trailer, so....?

[CBWELL]

Not a problem, mojo, as long as you don't put the brakes on in the TV at the same time. Then you have 2 feeds to the brakes!!!! Reverse voltage !!! Bad!!!

[tjdonahoe]

I don't' understand about unhooking the cord first,as far as 2 feeds , positive going to the brakes,it is fine as both are 12 volt.Far as checking the switch ,just pull the cable out and try to drive forward,....no magic to it...

[paiceman]

I do it his way seems to work. Jack up the trailer so the wheels on two sides spin. Spin the wheels, pull the pin, if they stop it works, if not something is amiss, usually a low or dead battery.

[Protagonist]

Originally Posted by tjdonahoe

I don't' understand about unhooking the cord first,as far as 2 feeds , positive going to the brakes,it is fine as both are 12 volt.Far as checking the switch ,just pull the cable out and try to drive forward,....no magic to it...

A valid test has the breakaway switch powered by the trailer battery only, because that's the way it will happen if it's really needed; the umbilical cable will come loose when the trailer breaks away. So if the trailer brakes don't work off the trailer battery only, they don't work at all in a breakaway situation.

As for reverse voltage, I haven't analysed it to see if that's true. I always test the breakaway switch before connecting the umbilical, so I haven't felt the need to analyze it.

[CBWELL]

Do a google search on the topic. Everywhere they tell you NOT to leave the electrical connected when testing. Your trailer battery feeds the brakes when the switch is pulled on the breakaway. If the brake pedal is pressed, with the main wire harness connected to the trailer, you will be feeding the tralier brakes with a second feed. Everywhere it warns you not to do this, as damage will occur. I am NOT going to try it to find out what will happen. Might feed in series, thus 24V to brakes. Fried brakes???

[rmkrum]

Problem is that most modern brake controllers use a solid state switch to power the brakes. Feeding voltage into the umbilical brake line can cause damage to that part of the controller and render it useless. Unplug it first for protection. And, as mentioned, you want to be sure the trailer batteries will power the brakes properly as well.


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[silver 67]

I have read that once you pull the pin you should not leave it out but a few minutes as it is sending a full12 volts to the brakes which can heat up and warp the hubs and other problems.

[B00merang]

I hope you'll tell me that I'm not completely irresponsible. My cable to the brake controller tore some time back (don't remember how)...I never had it fixed, and the wheels to Daisy are turning fine. Advice/admonitions please (much prefer the former). jon

[Protagonist]

Originally Posted by B00merang

I hope you'll tell me that I'm not completely irresponsible. My cable to the brake controller tore some time back (don't remember how)...I never had it fixed, and the wheels to Daisy are turning fine. Advice/admonitions please (much prefer the former). jon

The breakaway switch is triple-redundant safety equipment, after the hitch and safety chains, both of which would have to fail before the breakaway switch does its job. So you're probably taking only a very small risk, physically.

Legally, breakaway switches are required in most states for trailers that have trailer brakes. You would have to check the regulations of the state in which the trailer is registered to see if they're required for yours. So you may be taking a larger risk, legally. If you live in a state that requires annual vehicle inspections, and those inspections include trailers, then a damaged breakaway switch should show up during the inspection, and you'd have to get it fixed before you could pass the inspection.

[B00merang]

thank you, Protagonist...that was my line of thinking. I'll get it fixed before this traveling season starts (Florida and Alaska). jon

[slowmover]

Originally Posted by rmkrum

Problem is that most modern brake controllers use a solid state switch to power the brakes. Feeding voltage into the umbilical brake line can cause damage to that part of the controller and render it useless. Unplug it first for protection. And, as mentioned, you want to be sure the trailer batteries will power the brakes properly as well.

Correct. I blew out a cheap controller this way.

[Msmoto]

Having a piece of equipment which does not meet code creates a liability issue one does not want to find themselves in if an accident occurs. Good idea to get it repaired.

[slowmover]

Originally Posted by ghamr

Is there a way and/or is it necessary to test the break-away switch that activates the AS breaks if the camper comes loose from the TV.
Later: Just read some of the posts below & seems my questions are answered.......

See the 2008 thread by John Barca (JBarca) on www.rv.net entitled

WD Safety Chains Hookup

for the relationship of chains and brake switch lengths.

[idroba]

Originally Posted by silver 67

I have read that once you pull the pin you should not leave it out but a few minutes as it is sending a full12 volts to the brakes which can heat up and warp the hubs and other problems.

I accidentally pulled the pin on my break away switch and it was out for 3 days. I was hooked up, so no battery run down. No damage to the brakes, magnets or anything else at all.

The current is about 3 amps per brake, and at 12 volts that is around 36 watts. Considering the heat generated from actual braking going downhill etc, the 36 watts is nothing. The hubs certainly will not warp. The brake magnet adheres to a plate inside the wheel, not the drum or hub.

I certainly don't advocate pulling the pin and leaving it out, but no damage will occur if it is done.

[Protagonist]

Originally Posted by silver 67

I have read that once you pull the pin you should not leave it out but a few minutes as it is sending a full12 volts to the brakes which can heat up and warp the hubs and other problems.

If the trailer is not moving when the pin is pulled then there is no friction, only pressure, and thus no heat buildup.

Think of it like this: Rub your hands together. They get warmer because of the skin-on-skin friction. Now just press your hands together. They don't get warmer because there's no friction, only pressure. The brakes are the same way if you pull the breakaway pin.

[J. Morgan]

Just my humble opinion, but I think that a controller damaged by current backing into it is a poorly designed product that I would want off of my vehicle and replaced with a more practical devise.