Most caravans and large trailers are legally required to have brakes. The laws are State based but are generally the same.
Weights. What does TARE, ATM and GTM refer to?
A visual description is the best way to understand the meaning of different weights.
Above: The TARE mass is the weight the caravan was when it left the factory. It is weighted with its jockey wheel and main wheels on the weightbridge. It has no water, no gas or optional accessories that are fitted after manufacture.
Above: The Aggregate Trailer Mass (ATM) is the weight of the caravan plus the permitted payload. It is calculated based on the lowest value of things like tyres, axle capacity etc. The payload includes everything added: water, gas, food, clothing etc. The caravan must be unhitched.
Above: The Gross Trailer Mass (GTM) is the weight of the caravan plus the permitted payload that is supported by the axles. The payload includes everything added: water, gas, food, clothing etc. The towball weight is NOT included.
The GTM is shown on a compliance plate which is usually located on the drawbar or inside the front boot. This is what a roadside weightbridge will check if you get pulled up.
The towball weight will vary depending on what load you have, and where it is stored, so it should be measured when you are fully loaded. Moving heavy items can alter your towball weight.
If your trailer weights less than 750kg, when loaded, you do not need any brakes.
Override brake laws
Override brakes are permitted when the GTM is under 2,000kg. Mechanical override brakes use the tow coupling to manually pull a cable connected to the trailer's brake drums in much the same way as pulling up the handbrake.
Hydraulic override brakes are similar but use hydraulic pipes/fluid between the coupling and brake cylinders.
Electric brakes* laws
Electric brakes are commonly used on caravans and trailers over 750kg but are legally required (*limited alternatives maybe available) on all caravans and trailers with a GTM over 2,000kg.
Electric brakes are automatically applied by the brake controller and can also be manually operated via a manual control on the brake controller which is installed within reach of the driver.
Your tow vehicle will need a brake controller if it does not have one. The catagory below shows what we sell, plus an article to help you decide what features you may need.
Breakaway system laws
All States require that caravans / trailers over 2,000kg GTM also have a breakaway system. A breakaway system is a way of automatically turning your caravan electric brakes on in an emergency. If your caravan was to become uncoupled while towing the breakaway system has a battery that will operate the brakes for at least 15 mins.
Remote battery monitors
Remote battery monitors are used to provide the driver with an indication of the charge in the battery used to power the electric brakes when the emergency system is activated. These were mandatory in NSW from 2007 to 2016 however it appears the laws have been relaxed. Many people still believe they are a good idea to have and most caravan manufacturers would recommend having one.
Remote monitors to can be purchased separately to suit most existing breakaway systems.
Currently there is not a remote monitor available for the Tekonsha breakaway system.
National Trailer Regulations
NSW - Local Rules
QLD - Local Rules
VIC - Local Rules
WA - Local Rules
SA - Local Rules
NT - Local Rules
TAS - Local Rules
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