ABYC standards are a bit tougher when it comes to battery installation than European standards, at least from what I’ve seen on many of the CE-marked boats I’ve inspected that were imported to the United States. For example, wing nuts, which often come with a new battery, shouldn’t be used, yet I recently found them in use on a brand-new CE-marked boat. Again, these are not compliant with the latest ABYC standards. In fact, wing nuts are now not to be used on wires sized 6 AWG or greater, based on ABYC Standard E-10. The reason is simple: They tend to come loose and could cause an arc and overheating, possibly even shutting down your electrical system completely or setting fire to nearby materials.