Systems using two modules are generally used for RV's and boats, so you can usually use the extension cables along the entire distance. That way you can use less expensive wiring (such as THHN rated insulation) inside the electrical conduit to cover greater distances at substantially less cost than the MC4 cables.

Our SVB experts explain how to use solar energy on your boat and help you find the right system for your vessel. Finally, to prevent sea air and rain from corroding the electrical business ends, a compatible "grease" could be applied that wouldn't attack the rubber or plastic body of the connector but would keep the metal protected.Once you've got the two modules connected in series, you need to use MC4 cables to bring that power to wherever your electrical equipment is located (usually a circuit breaker and a solar charge controller). When we got our 550 the suitcase choices were too expensive for my taste so I bought an inexpensive panel that would fit in our small TV. If you're asking this question, you've probably noticed that most modern high power solar modules are manufactured with wire leads that have latching connectors on the ends. You can then strip back the insulation from the cut ends and terminate them to a bus bar or circuit breakers.

Just like an extension cord has a male plug on one end and a female plug on the other, an MC4 extension cable has a male connector on one end and a female connector on the opposite end.Just in case you need more to think about - you might consider not purchasing the solar controller with the panel and locating a controller in the trailer. The SAE connectors are the same design as the flat 4 trailer wiring hitch connectors although they are only 2 connections wide, not 4. Easy to use, charge your solar with the adapter cable and for easily connecting to RV solar panels, suitable for most the solar panel kit. One type accepts two male MC4 connectors on the input side and has a male MC4 connector for its output.

Due to the locking mechanism of the MC4 connectors, they will not come unplugged and are well suited for outdoor environments. Even though MC4 connectors appear to shield the actual electrical contacts when connected, when disconnected, those contacts are just as susceptible as SAE connectors to salt air, etc. I cut off the ends of an heavy duty extension cord --- the female end, I attached that to the twistlock which goes to the camper. You need to keep the polarities straight with the SAEs but other than that I find them excellent, simple and have had no problems at all. I can say, as someone who likes to park in the shade, I am often placing my solar panel at the limit of my wire's reach (20-25').

Would animal pee, an errant cup of coffee, or a little drizzle when you’re away from camp short the system? But I think for the amount of time I would be charging on the road, getting something over 13 volts to the battery in the field will be adequate.

If you're only using two modules, or two strings of modules, the easiest method is to use MC4 multibranch connectors.

For systems using a combiner box, you simply choose a length that, when cut, is long enough to be terminated into the box. Being a novice at setting up a solar system, I had many questions along the way, and the team at Sun Powered Yachts were always there to answers my questions and provide support. I have spent forever analyzing the pros and cons of all the choices involved, from panels to controllers to connectors to wire gauge, to how long an extension to run. I had the same concerns about the MC4 connectors but have been using them for 6+ years now without a problem.