Fuse strips & CF fuses
Main fuses for trucks and trailers are a critical element of every professional commercial vehicle electrical installation. In the heavy transport sector, electrical systems operate under continuous load, making reliable overcurrent protection essential to prevent damage to wiring, distribution blocks and connected components. Selecting the correct main fuse depends on the rated current, the position within the circuit and the applicable standards.
The strip fuse for trucks is one of the most widely used protection components in vehicle electrics. This type complies with the DIN 43560 standard, which precisely defines the dimensions, melting characteristics and electrical properties of strip fuses. Because DIN 43560 prescribes a standardised geometry, strip fuses from different manufacturers are interchangeable in compatible holders, provided they conform to the same standard class. In the daily work of an HGV workshop or trailer manufacturer this matters directly: replacement in the field is faster and carries no risk of dimensional deviation.
The available current ratings in the DIN 43560 series range from 40 amperes to 300 amperes. The lower ratings, such as 40 and 80 amperes, are used to protect sub-circuits with a limited power profile. The mid-range classes around 100 and 125 amperes are suited to installations with larger power consumers such as hydraulic systems, winches or compressors on trailers and bodywork superstructures. The heavier variants at 160, 250 and 300 amperes protect main circuits in trucks and trailers where total current throughput is substantial. The heavy duty fuse for trailers is frequently specified in the 250A and 300A ratings because multiple circuits are fed simultaneously through a single main protection device.
Alongside the DIN 43560 strip fuse, the ANL fuse is a commonly used type for main circuit protection in 24V commercial vehicle installations. The ANL fuse 24V is fitted directly into the main power cable, typically as close to the battery as possible, and protects all downstream wiring. The ANL format is internationally recognised and is standard practice in the truck and trailer industry for protecting battery connections, inverters and large distribution systems. The compact form factor and simple bolt-down fixing make ANL fuses suitable for installation in confined spaces such as the battery boxes found on tractor units and semi-trailers.
A third category within main fuses is the CF8 design with an integrated battery terminal clamp. This type combines the fuse and the terminal clamp in a single component, placing protection directly at the battery pole without additional wiring or intermediate holders. CF8 main fuses are available in current ratings from 50 to 200 amperes and are used as primary protection in both 12V and 24V installations. The brown insulating nut developed specifically for the CF8 holder ensures an insulated and mechanically secure connection. The colour coding of this nut enables visual identification in complex installations, reducing inspection and maintenance time.
For application in the truck and trailer sector, the combination of DIN 43560, ANL and CF8 main fuses means that technicians and trailer builders have a standards-compliant solution available for every position in the circuit. In new trailer construction, strip fuses conforming to DIN 43560 are routinely included in the fuse schedule, while ANL fuses 24V are used for the main power cables to the battery or distribution unit. CF8 terminal clamp fuses are practical for retrofits and installations where available space is limited. HGV workshops carrying out repairs to existing electrical systems work with all three types, depending on the original layout of the vehicle. The main fuse for an HGV is therefore not a generic component but a technically specific part that must be selected in accordance with applicable standards based on the actual current load and its position within the circuit.