Trailer breakaway cable

ridgy said:
In this case I will put a chain on the handbrake similar to the alko style but it won't snap so that in the event of a failure will apply the trailer brakes such that the car will be braked slowly. Obviously if the car brakes then the hitich goes in to the bumper but better than the alternative.
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I would strongly suggest attaching the chain to a strongpoint on the trailer, and not the handbrake. As someone said up there somewhere (^^^) on that sort of hitch the brake doesn't stay on, so apart from an initial jolt you get no real benefit from attaching to the brake. If the link breaks you're in trouble and if it doesn't you're likely to knacker the brake mechanism. Which is a particular shame if you've justforgotten to disconnect the link.

I have a similar hitch on my Hunter 490 trailer, and I used a chain looped through the trailer A-frame (which you don't have, obviously) and the towbar (not the hitch) so I have a reasonable chance of staying linked to the trailer if something does wrong.
 
I'm not up to date with UK trailer laws. From what I can remember in NZ, as well as a breakaway chain, you also have to have a thinner chain to trigger the energy store which applies the brake, and holds it on.
You also had to have a certificate of road worthiness if I remember.
 
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Mercury Rising said:
There you are then. Another excellent reason to have left the EU. :D
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its a PITA to have to trot along to testing station each year - but given some of the trailers seen in UK and even here - I think it may be a better idea.

Years ago - I had one of those typical blue powder coated box trailers common in UK in the 80's .... slowly it rotted of course till finally I decided it was time to stop using it.
When I went to cut it up - it literally fell apart ..... leaving a base triangular frame .. which I thought might be good for a flat board dinghy carrier .... till we turned it over ....... and found the seriously weakened parts.
In those days - I could have carried on using it legally on the road .............

Over here - it would never have been accepted on the road well before that condition.
 
The main purpose of the cable is 1) to stop the front of the trailer hitting the road. If the nose of the trailer digs into the road, where it goes next is anybody's guess.
Secondary function is some steering of the trailer.

slamming on the trailer brakes and hoping is not a good approach, except in the case of the trailer running away backwards down a hill.
If you've got a trailer, suddenly without towing vehicle, doing 50 and you slam the brakes on, it could go anywhere.
 
JumbleDuck said:
I would strongly suggest attaching the chain to a strongpoint on the trailer, and not the handbrake. As someone said up there somewhere (^^^) on that sort of hitch the brake doesn't stay on, so apart from an initial jolt you get no real benefit from attaching to the brake. If the link breaks you're in trouble and if it doesn't you're likely to knacker the brake mechanism. Which is a particular shame if you've justforgotten to disconnect the link.

I have a similar hitch on my Hunter 490 trailer, and I used a chain looped through the trailer A-frame (which you don't have, obviously) and the towbar (not the hitch) so I have a reasonable chance of staying linked to the trailer if something does wrong.
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The chain of course can be attached anywhere to create a strong link between car and trailer - but the breakaway cable as I understand must be attached to the handbrake lever. We can accept that the brake will only stay on if the cable is tensioned - which should in theory happen if the hitch lets go from tow ball and chain takes up .... assuming the cable is set to similar length as the chain ...

The car stopping should hopefully still have chain and cable at tension ...

I am starting to recall my Alacrity trailer .... and the one for my Snapdragon 23. They were identical to the series of caravans I had ... I cannot recall them having chains ... but they did have cable to the brake lever. 1980's ... till early 1990's. They all had the hitch activated over-run brake via the brake lever.

I have a feeling that my last caravan had a brake system that was extra to the lever rod system. I seem to recall that it was activated by the van running backwards ... at very slow speed as in reversing by car / manual movement - it was OFF ... but if the van was running away as in down a hill etc. - it would come on ... its only a feeling ... I cannot be sure.
 
lw395 said:
The main purpose of the cable is 1) to stop the front of the trailer hitting the road. If the nose of the trailer digs into the road, where it goes next is anybody's guess.
Secondary function is some steering of the trailer.

slamming on the trailer brakes and hoping is not a good approach, except in the case of the trailer running away backwards down a hill.
If you've got a trailer, suddenly without towing vehicle, doing 50 and you slam the brakes on, it could go anywhere.
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Sorry - you are mixing up the CHAIN with the Breakaway cable ... the two have completely separate functions.
 
Refueler said:
As an aside ... its an interesting item - trailer regulations.

Here as in many Eu and other countries - trailers have separate registration, technical inspection, insurance, number plates etc. This makes a bit of a 'niggle' for any trailer from the UK.
UK has as I believe now - still not separated trailer from being an extension of the car on the road. This means that any trailer from UK coming to ie Latvia has a short period of exemption - but then must submit for inspection and authorised use. This also means that trailers must have manufacturers data plate fixed to it.
They are very strict on it here ...
Pal of mine in the CSDD (Latvian Inspection) was amazed when I described UK's trailers and lack of inspection. Especially when I talked about even the large caravans .....
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Pre 1973 we had UK Road Traffic act and British Standards on various types of trailers. Post 1973 we had EU Homologation of Regulations, which at the time covered trailer brakes, lights, etc and allowed either Country type approval ( if equal to EEC regs ) or equipment to proposed EEC regs. At this time we introduced EEC ( EU ) UK test authority for issuing EEC type approval, this was because the UK regs were out of step to EEC.

I spent 18 months around 1973 to get our equipment optimized to EEC regs and type approved, our customers then got there trailers approved to EEC regs, these were volume manufactures not one trailers. Last month I found a set of drawing for type approval of Sinclair Trailer horseboxes if anyone wants proof.

Why or what the problem is today I don't know, we used to though, but back then we made waterproofed axles for boat trailers, we spent weeks at MIRA proving round testing ride handling, braking and stress in trailer under-gear and chassis.

Brian
 
"halcyon" .... its not the standards to build to ... its the continued use and inspection of to ensure safe trailer.

UK as far as I am aware still does not require MOT of a trailer to be able to continue using. Does not require separate insurance for it in case of 3rd party. Does not have separate number plate.

Here we have to submit trailers every year for inspection. I have a Registration document ... insurance certificate ... holographic sticker showing inspection date and expiry ....
 
Refueler said:
The chain of course can be attached anywhere to create a strong link between car and trailer - but the breakaway cable as I understand must be attached to the handbrake lever. We can accept that the brake will only stay on if the cable is tensioned - which should in theory happen if the hitch lets go from tow ball and chain takes up .... assuming the cable is set to similar length as the chain ...

The car stopping should hopefully still have chain and cable at tension ...

I am starting to recall my Alacrity trailer .... and the one for my Snapdragon 23. They were identical to the series of caravans I had ... I cannot recall them having chains ... but they did have cable to the brake lever. 1980's ... till early 1990's. They all had the hitch activated over-run brake via the brake lever.

I have a feeling that my last caravan had a brake system that was extra to the lever rod system. I seem to recall that it was activated by the van running backwards ... at very slow speed as in reversing by car / manual movement - it was OFF ... but if the van was running away as in down a hill etc. - it would come on ... its only a feeling ... I cannot be sure.
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We had breakaway cables and couplings with hydraulic overrun dampers from the 1960's, brakes will only operate if tow vehicle is going slower than the car, as in braking. In the 70's we introduced auto reverse brakes that allowed reversing with out having to engage reverse lock.

Brian
 
Refueler said:
"halcyon" .... its not the standards to build to ... its the continued use and inspection of to ensure safe trailer.

UK as far as I am aware still does not require MOT of a trailer to be able to continue using. Does not require separate insurance for it in case of 3rd party. Does not have separate number plate.

Here we have to submit trailers every year for inspection. I have a Registration document ... insurance certificate ... holographic sticker showing inspection date and expiry ....
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If it is not a EU regulation, it would not / or did not cover the UK, and would be classed as a local reg to that Country, up to owner to meet.

Commercial trailers in the UK have a annual test, private trailers come under road traffic requirements for a safe vehicle, spot checks by Police.

Brian
 
No use having a chain attached to the handbrake unless you have an energy store fitted. An energy store will also stop the auto reverse system working, so if the trailer becomes detached going uphill it will not roll back down.
 
KREW2 said:
No use having a chain attached to the handbrake unless you have an energy store fitted. An energy store will also stop the auto reverse system working, so if the trailer becomes detached going uphill it will not roll back down.
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Handbrakes were designed to hold the trailer going up / down a 1 in 4 gradient, thus breakaway brake as well.

Brian
 
lw395 said:
The main purpose of the cable is 1) to stop the front of the trailer hitting the road. If the nose of the trailer digs into the road, where it goes next is anybody's guess.
Secondary function is some steering of the trailer...…
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I don't know where you've got that idea from. A typical cable or chain won't stop the coupling from hitting the road, it's too long to do that. And no way is a trailer coupling going to penetrate tarmac and "dig in".

You're second bit is what its about - keeping the trailer attached to the towing vehicle.
 
I look after a collection of gig trailers, all manufactured under the current EU and UK regs. They’re all fitted with a lightweight steel breakaway cable which is connected to the handbrake of the trailer - no chains or similar. If the hitch parts company with the tow vehicle, the cable tightens, applies the trailer handbrake and then snaps: there’s no way it would take the weight of the trailer plus load. The object of the cable is to apply the trailer brakes and bring it to a stop.
The idea of a chain linking tow vehicle to trailer is to prevent the trailer detaching from the tow vehicle completely. A chain should therefore be fitted to trailers which do not have the breakaway type brakes fitted.
The whole idea of either is to stop the trailer becoming an uncontrolled missile like the speedboat and trailer which recently took out a Police camera van.
Looking at the OPs pictures, the hitch and brake mechanism is of a fairly old model, with a flip over catch which is only employed when the trailer is unhitched and you want to keep the brakes on. Leaving that catch flipped forward when towing will lead to burnt out brakes in pretty short order (my father found this out with our caravan in the 60s....). Attaching a breakaway cable to that type of brake will do nothing in the event of the hitch becoming disconnected.
 
duncan99210 said:
The object of the cable is to apply the trailer brakes and bring it to a stop.
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So when the breakaway cable breaks what holds the brake lever in the on position.

It there is nothing holding the trailer brakes on they will simply release and the trailer will carry on moving.

BTW crossing a safety chain stops the chain jumping off the tow ball hitch.
 
Rogershaw said:
So when the breakaway cable breaks what holds the brake lever in the on position.

It there is nothing holding the trailer brakes on they will simply release and the trailer will carry on moving.

BTW crossing a safety chain stops the chain jumping off the tow ball hitch.
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The chain shouldn't be on the ball hitch, it should be fixed to the vehicle.
 
Rogershaw said:
The ball hitch is attached to the vehicle. If you have hooks attaching the chain to the vehicle that adds a week link as the hooks could bend open releasing the trailer.
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And if the hitch comes off? And any connections should be as strong as the chain or cable.
 
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