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  Topic Review (Newest First)
08-24-2012 02:15 PM
Let there be light(s)!

On Wednesday I got the wires tucked away in their channels, outlet installed, connections made, and main switches flipped to ON.

No sparks, smoke or explosions, just lovely green LEDs softly glowing on the breaker switches and a working GFCI outlet in the main cabin. I declare victory!

Now I can install extra outlets at my leisure, and get back to sailing that girl. Just in time for the good September winds. My plan to use the dead August dog days for maintenance worked perfectly.
08-21-2012 04:58 AM
Re: Redoing shore power correctly

Galvanic isolator for 99.95 Galvanic Isolator Data Sheet

This is not a fail safe galvanic isolator, they are more expensive as you have found.

The schematic shows how to wire the panel, not the whole system.

Here is a link to ABYC A-28 Galvanic Isolators Standards.
08-18-2012 06:00 PM
Re: Redoing shore power correctly

It's interesting that connecting the AC ground to the DC common bus is an ABYC requirement, yet Blue Sea doesn't mention or show it on the schematic.

Galvanic isolators are referred to as being "inexpensive," yet the ones I've seen on line average around $200 or so. Does that sound right, and "inexpensive" is a very relative term, or am I looking at the wrong thing?
08-18-2012 05:40 PM
Re: Redoing shore power correctly

Connecting the AC ground to the DC ground bus is a requirement of ABYC. It does introduce corrosion issues that are solved with the installation of a galvanic isolator. Both the AC/DC connection and the galvanic isolator should be added at the same time.
08-18-2012 05:29 PM
What the instructions from Blue Seas didn't say

Namely, any mention of grounding the main AC panel to the common DC ground, i.e., the engine block. The schematic clearly shows only the ground from the AC source and then the individual grounds from each device.

I did ground the distribution panel to the engine out of respect for the opinion of many here who said it was a safety issue. I do not yet have a galvanic isolator, so I guess my question at this point is since Blue Sea didn't mention an engine ground as being necessary and I don't have the isolator, is it better for my electroactive metals and nearby boats to not have the engine ground?
08-16-2012 04:50 PM
Re: Redoing shore power correctly

Originally Posted by jaschrumpf View Post
In this case it would introduce one extra connection. I wouldn't use 14 awg wire, I'd use the 10 awg that I used for the main run.
You can use 14 for the short pigtail wire because as per ABYC that size single conductor wire not bundled, sheathed or in conduit and outside of engine compartment can safely handle 35 amps of current which is more than the shore power breaker rating. If 10 gauge is no problem, then go for it but the smaller wire can be used to make it easier (smaller lug, more flexible). I agree the design for the ground connection on that panel is a joke.

08-16-2012 01:44 PM
Re: Redoing shore power correctly

The three connections should fit if they are going off in different directions.

The other option is to drill and countersink for a #10 machine screw and use that.
08-16-2012 12:42 PM
Re: Redoing shore power correctly

In this case it would introduce one extra connection. I wouldn't use 14 awg wire, I'd use the 10 awg that I used for the main run. But it sure would be a lot easier to make the connection.

The only possible way to get all the ring terminals on the little tiny screw is to bend them so they "stand up." Not enough room in there to lay 'em down as usual.

I just can't figure out that design. The four hot and neutral terminals (two each) are big screws that have exactly one wire going to each one, while the ground that has to have three wires attached (one of them being a wire used by the main switch itself) is a puny little thing.

Seems dumb to me.
08-16-2012 10:05 AM
Re: Redoing shore power correctly

I would think 2 10 awg ring connectors stacked would make a better connection than any 14 awg run. The incoming AC source should be 10 awg minimum for 30 amp service.
As far as a pigtail, it does introduce more connections than necessary.
08-16-2012 08:40 AM
Re: Redoing shore power correctly

Originally Posted by fairbank56 View Post
Do not connect your safety grounds through that chincy ground screw. You need to provide another connection point within the junction box and pigtail another wire to that point. You can safely use 14 gauge wire for this.

That's what I need: a pigtail. I can join the three grounds to a screw in the back of the junction box. Luckily I bought a nice big one (4" x 4" x 4"), so there's plenty of room inside.

Thanks for the tip. Shoulda thought of that one.
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