Isolated DC Systems on Boats - Is my system GROUNDED or not? | Ask The Expert with NIGEL CALDER

[@superformOG]

too bad you dont show that shop, im assuming it has good quality electrical components, where i am its almost impossible to get good quality marine electrical components like ring terminals etc

[@BoatHowTo]

Thanks for your interest in the shop. We ship mostly to Germany, but upon request also worldwide. An English language version of the shop is available here: www.klabautershop.com/ ( the product translations are automatic so don't hesitate to ask if anything is not clear ). - Jan

[@superformOG]

@@BoatHowTo Im currently in the netherlands and its very difficult to get quality marine electrical parts

[@Lordlindef]

Nigel and jan. Can you make a disc about how to get a 10 ore 20kw generator el engine on topp of gearbox???? For us that motoring and have a lot of solar and litium. Use for regen and eldrive some times ❤❤❤❤

[@josephcrawley3095]

My 80s boat system is set up like this except the lightning ground is not connected to the DC negative. But the prop shaft is not isolated from the engine so there is some connection to the water to the DC negative. Would it be better to isolate that propeller shaft connection from the engine to make it a true floating system?

[@BoatHowTo]

If its an 80s boat it likely was not built with an isolated ground, or the isolation has been subsequently voided! I think you need to sketch all the principal wiring on the DC negative side and whatever is in the lightning protection system, galvanic bonding circuit, and where the AC grounding connection is made. If this really is an isolated DC system, the lightning protection system, bonding, and AC grounding should all go to a grounding bus with the DC negatives going to a separate DC main negative bus, and no electrical connection between the two (open circuit with an ohm meter). If it is a grounded DC system, the DC main negative bus and grounding bus need to be electrically connected. They may, in fact, be the same bus (we separate them conceptually, but not necessarily physically). Sketching the circuits will, in any case, be a useful exercise! If it is isolated, whether or not the propeller shaft is isolated from the engine generally makes no difference - the engine itself will be isolated via an isolated ground starter motor, alternator, and instruments.