What is ISO 25981 about?
ISO 25981 is an international standard on road vehicles that guides you to establish electrical connections of charging systems of towing vehicles.
ISO 25981 specifies dimensional characteristics, contact allocation, tests and requirements of 7-pole connectors for electrical connections of electronically monitored charging systems of towing and towed vehicles. The electronic monitoring system is designed to detect 12 V and 24 V nominal supply voltage and to limit the current to 50 A, and this is a connector without any braking capacity.
This electrical connection is intended for use with separable truck-trailer combinations in order to connect an additional battery pack of the trailer with the generator of the truck using an electronically monitored charging system
ISO 25981 further specifies a park socket used to receive and store the plug when it is disconnected.
Who is ISO 25981 for?
ISO 25981 on connectors for the electricalconnection of towing/towed vehicles is relevant to:
- Towing vehicles
- Towing authorities
- Road safety authorities
Why should you use ISO 25981?
7-pole trailer connectors are used for the electrical connection of turn lights, brake lights, lamps, and AUX/ABS power on vehicles with 12V and 24V electrical systems.
A number of ISO standards cover trailer connectors, ISO 25981 covers dimensional characteristics, contact allocation, tests and requirements of 7-pole connectors. These connectors are very important as it provides a connection between the vehicle being towed and the towing vehicle. With the help of this guidance, safety in the process of towing vehicles and the overall process can be improved.
What’s changed since the last update?
BS ISO 25981:2020 supersedes BS ISO 25981:2008, which is withdrawn.
BS ISO 25981:2020 includes some technical changes with respect to BS ISO 25981:2008. These are:
- References to ISO 4009 removed
- Corrections to Figure 2 socket
