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tlbsg
6th Aug 2009, 11:24 PM
am building a trailer and have to fit a breakaway system can i just use a battery mounted on trailer is the proper unit just a glorified battery

soundman
6th Aug 2009, 11:30 PM
pretty much.

you need a breakaway switch arrangement and a battery of sufficient size.
Some arrangement to charge the battery is probably a good idea too.

But if push comes to shove......are you confident that what you build would stand up to legal scrutiny in the case of an accident?

cheers

Yonnee
7th Aug 2009, 07:00 PM
am building a trailer and have to fit a breakaway system can i just use a battery mounted on trailer is the proper unit just a glorified battery

OK, first part of the question; Yes, you can just have a normal car battery mounted to the trailer, hooked up to the brakes via a break-away switch. The legal requirement in for all states of Australia is that the brakes must hold the trailer for 15 minutes, so your battery must cope with this current draw for that long. This also means you need to have some way of charging the battery while connected to the tow vehicle.

Second part; No, the "proper" Breaksafe unit has a little gel cell battery in it, as well as a facility for testing the system. The difference being the amount of times a Gel cell battery can be flattened and recharged compared to a standard lead-acid car battery before being "rooted". If the trailer is used daily, then it's not too much of an issue. But if not, then normal car batteries don't like sitting around not being charged.

Hope this helps you.

tlbsg
8th Aug 2009, 09:04 PM
yes i am soundman:)

soundman
9th Aug 2009, 11:45 PM
in that case.
As long as you have some electrical/electronic skill.....I do not believe its rocket science.

from what I understand there is no attempt to regulate or ramp braking force.

Its a case of connecting 12 volts across the brake magnets via the breakaway switch.

know the current draw of the brake magnets, size the battery appropriately, charging circuit if a small SLA battery is used some form of current limiting, and maybe a simple battery test facility

you'd probaly want to use a commercilay available breakaway connector.

cheers

Yonnee
10th Aug 2009, 01:53 AM
I don't think he needs to be told how to suck eggs. A simple question was asked, and a sufficient answer given.

soundman
10th Aug 2009, 11:29 AM
Yonnee you fail to understand the principle of a "discussion forum", if tlbsg is offended by my post he can tell me himself.
I am simply confirming what I think he suspects.

cheers