Frequently asked questions

Explore our FAQ items and useful tips here.

Is a rear fog light compulsory on my trailer?

The regulations regarding fog lights depend on the type of trailer.

All new trailers must be fitted with at least one rear fog light.
At BW Trailers, we consider safety as extremely important, which is why we fit all professional trailers weighing over 750 kg
with two fog lights.

Older trailers, regardless of their year of construction or maximum authorised mass, must also be fitted with a rear fog light.

Where can I find the unladen weight of my trailer?

The unladen weight or tare weight of your trailer is listed on the certificate of conformity under item 13.
All trailers manufactured and sold by BW Trailers include this document.

Where is the chassis number indicated on my trailer?

The chassis number (official VIN or Vehicle Identification Number) of a BW Trailers trailer is indicated on the type plate and is also stamped into the chassis.
VIN and type plate can be found in the right-hand quadrant at the front of the trailer, usually on the front metal cross member, as viewed from the direction of travel.

Where can I find the type plate on my trailer?

All trailers supplied by BW Trailers have a type plate that has been permanently fixed in the right-hand quadrant at the front of the trailer, usually on the
front metal cross member, as viewed from the direction of travel.

The type plate provides information on the origin, type and maximum permitted weights of the trailer.
The unique 17-digit VIN number is also indicated on the plate and is additionally engraved on the trailer’s chassis.

What is a breakaway cable and how should it be used?

Braked trailers must be equipped with a breakaway device, which must be connected to a fixed part of the vehicle.
This is the only way to activate the trailer’s brake in the event of accidental uncoupling while driving.
The various options for correctly connecting a breakaway cable to the towing vehicle are listed in the manuals provided by BW Trailers.

What is the correct tyre pressure for my trailer?

The maximum tyre pressure is indicated on the tyre.

Please note that the unit is often given in PSI (Pounds/Square inch).
As a rule of thumb, you can assume that 1 bar = 14.5 PSI.
The recommended tyre pressure for most of the tyres used by BW Trailers can be found below:

Type of tyre
Max.tyre pressure
(bar)
155/80R132,4
165R13C4,6
185R14C4,5
195/50B106,0
195/50R13C6,5
185/60R12C6,5

What type of plug/connection does my trailer have?

All trailers from BW Trailers with an MAM up to 750 kg are fitted as standard with a 7-pin plug in accordance with ISO 1724 and are optionally available with a 13-
pin plug in accordance with ISO 11446.
Braked trailers over 750 kg are fitted as standard with this 13-pin plug (also known as the Jaeger connector).
Special adapters are available for both plug variants and a wiring diagram is included in all the manuals provided by BW Trailers.

What is the MAM of my trailer?

MAM stands for the Maximum Authorised Mass of the trailer and is the maximum total weight the trailer, including all variable contents, may weigh.
The MAM is a fixed value determined by BW Trailers and indicates the maximum weight that can be moved safely with this type of trailer.
The MAM can always be found on the certificate of conformity or on the chassis plate fixed to the trailer.

What is the loading capacity of my trailer?

The loading capacity of a trailer depends on the mass in running order of the trailer and its Maximum Authorised Mass (MAM).
The useful loading capacity of the trailer = MAM – mass in running order.