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CharlieJ · 12-07-2009, 23:52

The responses to the question are good...I just did the mod for a friend's boat. The 30 amp Marinco male end retails for about $20 at West Marine and I cut off the male end of the extension cord and installed the Marinco.

However, I would be remiss if I did not caution you about using an automotive battery charger on board a boat. Most of them tie the neutral to the safety ground at the transformer in the charger, which can lead to problems should a fault occur in the charger that could be reflected in your DC system. The charger is an interface between shore AC and vessel DC. A properly wired marine rated charger able to meet your modest requirements should cost less than $100.

One other problem with your automotive type charger is the lack of over current protection in the B+ output from the charger. Many quality marine rated chargers are "self limiting" and do not require the OCPD.

12-07-2009, 23:52	#5
CharlieJ Registered User Join Date: Dec 2008 Location: St. Petersburg, FL Boat: Gulfstar Long Range Trawler; 53'; BearBoat Posts: 163	The responses to the question are good...I just did the mod for a friend's boat. The 30 amp Marinco male end retails for about $20 at West Marine and I cut off the male end of the extension cord and installed the Marinco. However, I would be remiss if I did not caution you about using an automotive battery charger on board a boat. Most of them tie the neutral to the safety ground at the transformer in the charger, which can lead to problems should a fault occur in the charger that could be reflected in your DC system. The charger is an interface between shore AC and vessel DC. A properly wired marine rated charger able to meet your modest requirements should cost less than $100. One other problem with your automotive type charger is the lack of over current protection in the B+ output from the charger. Many quality marine rated chargers are "self limiting" and do not require the OCPD. __________________ Charlie Johnson JTB Marine Corporation "The Devil is in the details and so is salvation."