Selecting the right wire size for your marine electrical installation is crucial for safety and reliability, but the calculations can be complex. This calculator simplifies the process by considering all the critical factors that affect wire sizing in marine environments according to the ISO 13297 standard from the International Organization for Standardization.
When you're running electrical cables on a boat, it's not as simple as matching the wire to the circuit breaker size. Distance, voltage drop, temperature, and installation method all play vital roles in determining the correct wire gauge. A wire that's adequately sized for current carrying capacity might still create excessive voltage drop over longer distances, potentially affecting the performance of sensitive electronics or causing motors to run below their rated speed.
This calculator takes into account:
- Circuit amperage requirements
- Total wire run length (distance to load and back)
- System voltage (12V or 24V)
- Maximum acceptable voltage drop (typically 3% for general circuits, 1-2% for critical equipment)
- Installation conditions (free air, bundled, or in conduit)
- Ambient temperature factors
Simply enter your specific parameters below, and the calculator will recommend the minimum safe wire size for your application. Remember that while the calculator provides accurate technical recommendations, it's always good practice to consider future expansion needs and round up to the next available size when in doubt.