When ordering a towbar to be fitted you need to decide which type of towing electrics that you will need.
There are 3 types of towing electric socket used in the UK.
These are Single 7 Pin electrics (12N), Twin 7 Pin electrics (12N & 12S) and Single 13 Pin electrics.
The type of socket that you need depends on what you are towing.
Whether you are towing a large caravan, or just using your towbar to support a cycle carrier, you will need some electrics with your towbar.
It is a legal requirement to have lights on the rear most point of your vehicle.
If you are towing a caravan with 13 pin electrics and also tow a trailer with 7 pin electrics there are adaptors available HERE.
13 Pin Electrics
13 Pin Electrics is the most modern and versatile option for your towbar electric socket.
This is used for caravans and trailers with more complex electrical systems (e.g., for fridge, battery charging, and additional lighting).
This has replaced the two separate sockets (Twin Electrics) which were fitted to UK caravans up until 2008. The 13 pin socket is essentially the two 7 pin sockets merged in to one.
All caravans manufactured in the UK from 2008 are fitted with an ISO 13 pin connector as standard. This system uses one socket with 13 pins inside, instead of the traditional two separate 7 pin sockets.
13 pin sockets are also used on some vehicles especially with detachable towbars when there isn't enough room to mount two separate sockets behind the bumper.
The big advantage of the 13 pin socket is that it twists and locks in to place making the connection to your trailer or caravan much more secure.
Single 7 Pin Electrics
Single 7 Pin Electrics also known as 12(N), are fitted as standard with any towbar.
They provide power from the towbar to the lights on a trailer or caravan. If you're only going to be towing a trailer this is generally all you need, although some more modern trailers are not coming with 13pin electrics, so it is always best to check.
You can tow a caravan using only single electrics, but the interior functions of the caravan, such as the fridge, wouldn't have power to them. You would need an electric adaptor if your caravan has 13 pin electrics.
Even if you will only be using the towbar for a cycle carrier you still have an electric socket fitted so that you can power a light board over the bikes, or the lights on the carrier itself.
Twin 7 Pin Electrics
Twin 7 Pin Electrics, also known as 12(S), used to be fitted for towing a caravan built prior to 2008.
The extra grey socket provides power to operate the interior functions of the caravan such as the interior lights, run the fridge and charge the battery while you are towing.
This type of socket has been replaced on caravans built after 2008 in the UK. New caravans now use the 13 pin standard socket shown above.
We no longer fit towbars with twin electric sockets, because it is far tidier and more secure to use a 13 pin socket, with a 13 to twin socket adapter if you do need to tow an older caravan.
Pins and Functions
13-Pin Socket (ISO 1724) Pins and functions:
- Left-hand indicator
- Right-hand indicator
- Brake lights
- Tail lights
- Earth (ground)
- Reverse lights
- Fog lights
- Auxiliary power (for powering additional functions or charging a battery)
- Permanent live (for powering accessories in the caravan or trailer)
- Fridge circuit (for powering a caravan fridge or cooling system)
- Battery charging (to charge the battery in the trailer or caravan while towing)
- 12V auxiliary power (for other systems, e.g., lighting)
- Not often used (varies by specific trailer or vehicle)
7-Pin Socket (ISO 11446 / 7-way) Pins and functions:
- Left-hand indicator
- Right-hand indicator
- Brake lights
- Tail lights
- Earth (ground)
- Reverse lights
- Fog Light