DC To AC Grounding ?

[Larry Glover]

Should the DC ground be connected to the shorepower AC ground? Mine isn't. It seems it could prevent electrical shock in some cases but could it add to galvanic corrosion?

[Bryan Mehus]

Larry,
The short answer is no, the A.C. system should not be bonded to the D.C. system.Try http://marinesurvey.com/yacht/ElectricalSystems_Intro.htm for a more difinitive answer.
Bryan

[trull]

This has been the topic of several long threads in the past, and there are more than several opinions.

Another short answer is that both the Coast Guard and ABYC recommend connecting the AC ground (green wire) to DC ground. To prevent galvanic corrosion while on shore power you need a galvanic isolator or an isolation transformer. Here is a link HEART INTERFACE (http://www.heartinterface.com/GroundingInverter-ChargersonBoats.html). The first section explains this reasoning. In this litigious world, I wouldn't dare recommend anything else.

Another link is ABYC (http://www.bluesea.com/abyc.htm) which gives the ABYC requirements.

Pascoe's article is somewhat vague. For instance, a DC system is seldom free-floating or isolated, as the DC negative is most likely connected to the engine starter/engine block and then to shaft/propeller/seawater. He also doesn't talk about shipboard AC generators and inverters which must be grounded on the boat.

Describe your system?
Look at some schematics on my web site.