Cable connectors

Crimping & connection technology for onboard electrics – cable lugs, crimping tools & secure cable connections

Professional crimp connections are the standard in onboard electrics on boats, yachts, motorhomes and expedition vehicles. Compared with soldered joints, properly crimped cable lugs offer lower contact resistance, higher vibration resistance, better corrosion resistance and a longer service life under the typical loads on board.

In brief: Professional crimp connections with non-insulated cable lugs and matched crimping tools are the most reliable connection technology for modern onboard systems – especially with lithium batteries, inverters and high-current loads.

The cable configurator calculates the right cable cross-section for your cable lug connection from current, cable length and system voltage – including fuse sizing and a ready parts list.

Crimping or soldering – which is better for onboard electrics?

In professional onboard electrics, crimp connections are preferred over soldered joints. Soldered joints have several disadvantages in onboard installations:

Disadvantages of soldered joints in onboard electrics:

• Cold solder joints increase contact resistance and generate unwanted heat
• Solder stiffens the copper strands of the cable – under vibration this leads to material fatigue and broken cables
• Increased risk of corrosion from flux residues
• Lower long-term reliability under the typical vibration and moisture conditions on boats and vehicles

Advantages of professional crimp connections:

• Low contact resistance
• High current-carrying capacity
• Maximum resistance to vibration and shock
• High corrosion resistance
• Long service life even under high mechanical loads

Which cable lugs are suitable for professional crimp connections?

For the highest connection quality in onboard electrics, non-insulated cable lugs combined with professional crimping tools are recommended. Compared with conventional insulated versions, non-insulated cable lugs offer:

• A mechanically and electrically optimal crimp connection
• Better control of the crimping process
• Higher connection quality with larger cable cross-sections
• Lower contact resistance

Which onboard applications need crimp connections?

Professional crimp connections should be used in all areas of onboard electrics:

• Battery cables and main power cables – high currents, high demands on contact resistance and current-carrying capacity
• Load connections – permanently secure connection even under vibration
• Control cables – reliable signal transmission
• High-current loads – inverters, battery-to-battery chargers, compressors, anchor windlasses

Especially in modern onboard systems with lithium batteries, inverters and battery-to-battery chargers, high-quality connection technology is essential, because these systems work with high charge and discharge currents and require low contact resistance.

Which crimping tools are needed for onboard installations?

Professional crimp connections require crimping tools matched to the cable lug and cable cross-section in question. The quality of the crimping tool has a direct influence on contact resistance, pull-out strength and long-term reliability of the connection. For non-insulated cable lugs, crimping tools with trapezoidal or heart-shaped crimp geometry are recommended.

Frequently asked questions about connection technology in onboard electrics

Why are soldered joints a problem in onboard electrics?

Solder stiffens the fine copper strands of the cable. Under the typical vibration on boats and vehicles, material fatigue and broken cables occur at these rigid points. In addition, cold solder joints can increase contact resistance, which leads to heat build-up and in the worst case to a cable fire.

What is the difference between insulated and non-insulated cable lugs?

Combined with professional crimping tools, non-insulated cable lugs allow a mechanically and electrically optimal connection with a better crimp result and lower contact resistance than conventional insulated versions. The insulation is then applied with heat-shrink tubing.

Which cable cross-sections can be processed with professional crimp connections?

With the right crimping tool, cross-sections from fine control wires up to large battery cables (e.g. 95 mm² or 120 mm²) can be crimped professionally.

Are crimp connections suitable for lithium battery systems?

Yes. Professional crimp connections with low contact resistance are the recommended connection technology for lithium battery systems working with high charge and discharge currents.

What causes cable fires in onboard installations?

Common causes are increased contact resistance from poor connections – for example cold solder joints, oxidised terminals or undersized crimp connections. These generate heat which, under continuous load, can ignite insulation.