Why do I need a brake controller?
Nearly every caravan now built has electric brakes fitted to the
caravan. These brakes require an electric current from a brake controller
mounted in your car, to make them operate. Any towed trailer or
caravan that weighs 750kg or more must be fitted with independent
brakes. Electric are the most common.
What about heavier trailers?
Caravans or trailers that exceed 2,000kg GTM must have brakes fitted
to all wheels and have a Break-Away system attached. The system
must be capable of automatically activating should the trailer become
detached from the tow vehicle. Under these circumstances the brakes
must remain applied for at least 15 minutes. These are in effect
a brake controller that is attached to the trailer with its own
How do electric brakes work?
Your caravan brake hubs have the traditional brake shoes inside,
they rarely have disc brakes.
The magnet becomes activated when power is supplied from your
brake controller. It is attracted to the inside flat face of the
rotating brake hub (not shown). The rotating hub causes the magnet
to rotate as shown (the magnet is attached to a lever
that pivots). When it pivots it causes both brake shoes
to spread and apply your brakes.
The brake controller that gets installed into your car (on or
near your dashboard), is what controls the power that gets sent to
the magnet at your wheel.
The controller has a direct connection to your battery for the
source of power. It also has a connection to the stop lights, usually
from the switch at the brake pedal. This tells the unit to supply
power to the magnet, via a direct wire from the controller. An earth
is also required.
There are many brands and models of brake controllers to choose
from, so I will discuss the common features first.
Voltage is first and perhaps most important item. They come in
12V and 24V and must match the power source in your towing vehicle.
Unless stated as 24V, the vast majority of controllers are for 12 volt
Number of axles
The controllers are made to suit a certain number of axles on the
towed caravan/trailer. This is really a measure of how much total
power they can provide. So even if the controller indicates it is
suitable for four axles it can still be used on a single axle,
tandem axle, or triple axle trailers.
It is important to provide adequate wire thickness when multiple
axles are braked.
Proportional or non-proportional?
Proportional brake controllers can use different methods
to sense the vehicles deceleration, and then apply proportional
power to the electric brakes. In other words, proportional controllers
deliver power to the trailer brakes in a direct relationship to
the actual physical deceleration of the tow vehicle. These must
be mounted within certain limits.
There are a couple of varieties of these - some need the controller
to be manually set up to suit the angle of installation, while the
more advanced will automatically level themselves.
These are generally more expensive than the following.
Non-proportional brake controllers can be time delay activated
or solid state. They apply a fixed amount of power to the trailer
brakes at any one time. However they are still adjustable from the
drivers seat for different driving conditions, e.g. in the wet. These
can be mounted at any angle.
Caravans Plus recommends Proportional Brake controllers for a smoother result.
Click the link below to see our full range of Brake Controllers:
Some very specialised trailer brakes are a combination of hydraulic
and electric. If this is your case you must ensure your brake controller
has this capacity.
This has little effect on braking performance, but the display can vary from
just a coloured LED to indicate the controller is working, to a digital display
showing effective power being delivered and a menu system to setup the controller.
The controllers may be mounted in a cradle under the dashboard or remotely
with just the controls protruding through dashboard.
In keeping with our recommendation for a proportional brake controller, the Hayman Reese Compact IQ offers the best features
for a remote mounted brake controller to date.
Hayman Reese does offer special wiring cables that can connect to some existing vehicle wire harnesses. Due to the large number of vehicles sold in the Australian market that do not meet the requirements for these, Caravans Plus does not sell these. Individuals may further research these under the SmartClick Wiring Solutions.
Fitting brake controllers onto or behind the dash, plus the wiring to the trailer connector is certainly within most DIY capabilities. All units do come
with installation instructions, and some additional items are required
like extra wire, wire connectors, and a fuse. We have a list of items
required shown here.
All the above separate items will be displayed if you type "KIT1000"
into our search box.
1 x Manual reset ATS circuit breakers, 20Amp for and one or two
1 x Manual reset ATS circuit breakers, 30Amp for three or four axles
1 x ATS standard blade fuse holder. In line
1 x Ring terminal (yellow) to connect to positive power source
2 x Connectors (yellow) suit 5mm wire
2 x Connectors suit 4mm wire
5mm Blue single core, take power from controller to rear vehicle
socket, 6 metres
5mm Black single core, battery power to controller, 3 metres
(below not sold by the metre, substitute colour or larger size)
4mm White extension for earth, 1 metre
4mm Red extension for brake switch, 1 metre
Models can come and go, and suppliers price to us can vary from
time to time. Our current recommendations are shown below. The P2 and P3 offer the same stopping quality with a superior menu system on the P3.
The Compact IQ is our recommended behind the dash controller.
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