Hi there,

This question doesn’t cover boat wiring itself, but it may be common enough for you to know the answer. I have a Lund fishing boat that has 2 batteries for the bow-mounted electric trolling motor, which are normally charged via a dual battery charger using standard household electrical power (115 V AC) and standard 3 prong extension cords.

I’ve noticed that the majority of serviced boat slips have 30 amp connectors for the larger boats but rarely any connection for smaller ones like mine. I’ve located an adapter (male 30amp to female 15amp), but I’m worried that if the voltage at the 30 amp service is wrong (e.g 220V), it could damage the charger or batteries or boat wiring.

I would appreciate your comments and advice.

Thanks,

Brian

Brian,

There is a recognized standard plug configuration for 30 amp 115 volt outlets and plugs. As long as it is not modified, it will not plug into any other receptacle.

If you are concerned with the receptacle that you are plugging into, test it with a digital voltmeter first. Test all 3 combinations of the 3 wires. You should read 115v between the Hot and Neutral and between the Hot and Ground. You should read 0v between the Neutral and Ground.

Let me know if you have any questions or concerns,

Kevin

Thanks Kevin,

I forgot to mention that the 30amp-15amp adapter has a label stating “Caution – do not exceed 15amp input”. Is there a way to test the amps at the marina connector or is this not a concern?

Brian

Brian,

This adaptor is plugged into an outlet protected with a 30 amp breaker. Limiting the current that passes through this adaptor is up to you. Your battery charger will only draw 1-2 amps and will cause no problems.

If you plug in several other items at the same time with the use of power strips and exceed the 15 amp rating of the 3 prong plug on your cord will probably catch on fire.

Kevin