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HowieE · 07-31-2010, 04:37 PM

What can one expect to find after the Brake Away Switch has been pulled and the battery run down to Zero Volts?

I have heard comments that this can do damage to the magnets but question that.

Yes the battery will most likely have to be replaced because of the deep discharge and age.

Kristi Foster · 07-31-2010, 04:49 PM

Our 1968 Avion originally came with this feature, a break away switch, but we do not know what it looks like or how it actually works. It sounds like a safety feature that I would like to have working again. A picture of one would be appreciated and any instructions. Thanks

Gene · 07-31-2010, 05:42 PM

Howie, it sounds like the brake breakaway switch was pulled, the magnets energized and the battery run down because of it. Is that correct?

I can't imagine how electromagnets can be damaged by no electricity. Most of the time they have none. As the voltage drops to zero, maybe there could be something that happens at low voltage, but I don't know what it could be.

Kristi, the breakaway switch locks the trailer brakes if the hitch comes off the ball and the trailer is getting farther away from the tow vehicle. It should be a length that permits it to work when the trailer is just being pulled by the safety chains. On newer models it is mounted near the front of the tongue and a wire goes to a clip or carabiner that is to be attached to the tow vehicle. Do a search on this item and you'll learn even more. When the wire pulls out the piece at the front of the switch, it closes the brake circuit and the brakes are locked. I believe some states, maybe all, require this as a safety feature so that if the trailer comes loose it will soon stop.

Gene

**azflycaster** · 07-31-2010, 06:25 PM

I have heard the same stories that the magnets will burn up, but it has all been second hand information. You could test them after you get a charged battery on the trailer. The magnets are almost a short circuit when they are functional. They are rated at around 4 ohms. With a good meter you could measure the resistance of each one and see if any are open or shorted.

Inland RV Center, In · 07-31-2010, 06:44 PM

If a trailer is plugged into city power, and the breakaway switch is pulled, it's been known to easily destroy the magnets, warp the drums, and to also discolor the bearings and spindles, to the extent that continued useage, would be a big gamble.

Without being plugged into city power, there can be enough wattage in a good battery/batteries, to absolutely burn up the magnets, before the voltage disappeared.

It's a very good idea, to pull the drums for a close visual inspection.

Travel trailer braking, should never be guessed at.

Andy

Splitrock · 07-31-2010, 07:27 PM

Wouldn't it be easy enough to wire a light into the brake circuit? There's only power to the brakes under two conditions. The light would be a warning that the switch is pulled. I have an external light on my freezer in my garage at home to tell me from across the room that it's got power. I've never said: "I wish I didn't have that indicator light!".

Gene · 07-31-2010, 08:58 PM

Howie's question was about no power to the brakes causing damage to the magnets because of a dead battery—at least that was how I understood it.

Airstream recommends pulling the breakaway and oiling it once a year, but to do it quickly.

Gene

bryanl · 07-31-2010, 10:28 PM

Quote:

Howie's question was about no power to the brakes

it's the journey, not the destination -- In order to drain the battery, you have to pull more than a kilowatt hour of electricity from it. That means a lot of heat is generated.

Brake magnets are not designed for continuous duty. They shouldn't be put full on for more than a few minutes.

Quote:

it's been known to easily destroy the magnets, warp the drums, and to also discolor the bearings and spindles,

wow! I'd think the magnet would fail before things got hot enough to do that much damage (unless you were rolling and the brakes were dragging).

Mexray · 07-31-2010, 11:52 PM

I can see where this would be a big problem if some vandal comes by and 'pulls' the break-a-way pin from the switch!

I've never given it much thought, but I guess it could happen if you're in the 'wrong' neighborhood...

I've also thought about a hidden SPST switch being wired into the POS, powered wire going to the BAW switch so pulling the pin won't activate the brakes - problem is - how does one always remember to flip the SPST switch back to the ON position, when back on the road....?

I suppose I could mount a GREEN LED panel light near the BAW switch that would be illuminated when the BAW switch has power and the SPST switch is in the ON position - LED light ON = circuit activated...for a reminder...

Any other thoughts?

Ray

Dave Park · 08-01-2010, 12:08 AM

I would put a small 12v buzzer into the circuit, so if the circuit is made, it will draw attention. The only times it should be in use is for testing, and in a separation.

bryanl · 08-01-2010, 07:54 AM

re: "I suppose I could mount a GREEN LED panel light near the BAW switch that would be illuminated when the BAW switch has power"

The problem is that the switch always has power and must for safety reasons. Anything put in series needs to be 'fail safe' so that the emergency function of the switch is not hindered.

It is parallel to the brake controller so there is no easy way to tell if it has been activated or the brake controller has been activated.

It seems that a device that would measure current over time would be needed. That would sound an alarm if the current to the brakes got above a certain threshold or the product of current and time indicated a problem. That kind of device would probably cost more than the risk.

**azflycaster** · 08-01-2010, 08:22 AM

"If a tree falls in a forest and no one is around to hear it, does it make a sound?"

I think the greatest concern is when the trailer is parked and no one is around. I had this concern when I parked my trailer at the RV storage yard so I would disconnect the battery when I parked it and then connected the battery when I got ready to take the trailer back out. This is a real pain in the you know what with the battery arrangement on a 70s trailer. I stopped doing this a few years ago and have never had an issue. I have been thinking that a hidden switch for the power to the tongue jack and break away switch might be a good solution. Since it would kill power to the jack it could not be overlooked when hitching up the trailer.

RLS · 08-01-2010, 08:23 AM

Is it possible to connect a 12 volt buzzer on the side of the switch that makes connection when pulled?

HowieE · 08-01-2010, 08:35 AM

Quote:

Originally Posted by RLS

Is it possible to connect a 12 volt buzzer on the side of the switch that makes connection when pulled?

Yes That would sound when the switch is closed and not any effect on the braking capacity. Sure would have saved the problem I am working with if they had heard the buzzer when they pulled away after parking the trailer.

The switch to the trailer tongue jack and brake away switch would require a heavy duty switch because of the currents drawn by these items but would work.

RLS · 08-01-2010, 08:52 AM

Quote:

Originally Posted by HowieE

Yes That would sound when the switch is closed and not any effect on the braking capacity. Sure would have saved the problem I am working with if they had heard the buzzer when they pulled away after parking the trailer.

Thanks HowieE, Since I just installed the new one, I'm going to put a buzzer on it. Should be easy enough to do. Just splice in on the connection that only gets power when the pin is pulled and ground it.
Here is the one I just put on:

HowieE · 08-01-2010, 09:08 AM

RLS

Keep in mind that the length of the cable wants to be short enough that the brake away switch pulls free before the chains go tight in a hitch failure. Looking at the factory supplied cable on your system that may not be the case. If so you want to shorten the cable.

I like to feed the cable through a D clip on the hitch release handle to insure the cable is supported across the top of the hitch and held so it can not get tangled in the hitch when turning.

HowieE · 08-01-2010, 09:10 AM

Forgot to post the picture.

Pahaska · 08-01-2010, 09:48 AM

My trailer lived in a storage yard and I have long worried about my breakaway being pulled by a vandal or by a curious child.

My Great Ideas column in the Airstream Life issue that should come out very soon has my solution to making the breakaway switch safe during storage.

I drilled a 1/4" hole in the metal just behind the plastic part of the switch. When I store the trailer, I put a small padlock through the hole and capture the loops at both ends of the breakaway cable. It is physically impossible to pull the pin without removing the padlock. By capturing both end loops of the cable, it is also impossible to forget to remove the padlock when hooking up. When the trailer is in use, I just lock the padlock in place. The padlock key lives on the same ring as the key to my hitch lock.

rmroy · 09-15-2018, 05:45 PM

Quote:

Originally Posted by Inland RV Center, In

If a trailer is plugged into city power, and the breakaway switch is pulled, it's been known to easily destroy the magnets, warp the drums, and to also discolor the bearings and spindles, to the extent that continued useage, would be a big gamble.

Without being plugged into city power, there can be enough wattage in a good battery/batteries, to absolutely burn up the magnets, before the voltage disappeared.

It's a very good idea, to pull the drums for a close visual inspection.

Travel trailer braking, should never be guessed at.

Andy

Hi Andy,
That is exactly what I've done. Most of the response that I've been getting about this says that if the wheels were not moving there will be no damage. Have a new 2018 Classic, so I'm hoping the damage you mention does not apply.

Thoughts?

paiceman · 09-16-2018, 02:51 PM

Quote:

Originally Posted by rmroy

Hi Andy,

That is exactly what I've done. Most of the response that I've been getting about this says that if the wheels were not moving there will be no damage. Have a new 2018 Classic, so I'm hoping the damage you mention does not apply.

Thoughts?

Actually Andy is spot on. When the safety brake away is activated maximum electric is sent to the magnets, which puts them on the brake drums. All the negative results Andy noted can happen