Shore power

[Capt. Ronnie]

Who here has shore power and if you have it do you have any pics of the installation???

 

[Saybrook Rich]

I may have some photos in a few weeks if you can wait that long. The boat is being rigged now. It should be available around the first week of May.

 

[gerg]

Shore power was one of my first projects. I don't think I have any pictures because it's a pretty boring task, but I'll take some next time I'm there.

Basic rig is shore power inlet to a double pole breaker, then to a gfci outlet, then to my charger. Pretty simple, the charger has an isolation circuit so I didn't need a seperate isolator.

I'm thinking one of these days I'll add a small microwave and maybe a power inverter. Too many projects though.

 

[dcunniff]

I recall that this came up about a month ago and listed what I had for a shorepower setup. I may have some photos this weekend that I can work on showing.

In brief, the shorepower connector is on the starboard side of the cabin in the vee in-line with the wiring console. Goes to a 6 breaker panel, where the top two are for the power and polarity test. I have one for a GFI outlet and one for the battery charger. I have a 20 amp 3-stage charger below my galley stove in a 2530. The 110V and 12V grounds come together.

Dana

 

[DaleH]

The 110V and 12V grounds come together ...

I believe that's where a LOT of people have a problem, as in DC electrical a black wire used to denote a "ground". In AC electrical, black is the color for a "HOT" wire, which carries the current. The AC "neutral" wire is white in color and carries the same current as the hot wire. As long as the current remains in this closed black/white wire circuit there is no danger, but if it should escape (a “fault” or “short circuit”), it will attempt to go directly to ground.

Most modern AC circuits also have a green third wire, which is a “grounding” wire. It's connected to the third prong of the common
3-prong plugs and it parallels the white wire and connects to neutral at the power source. It’s purpose is to ground the circuit when a short circuit occurs.

Note that as a result of this wire color confusion and the damage (and lives lost) as a result, that ABYC and I also believe BIA have recently changed the "ground" color for DC electrical to be a yellow wire, while red will still denote DC positive or "hot".

People were tying black DC and black AC wires together ... which causes problems :shock: .

CAUTION: This info is provided as FYI only ... DO NOT wire your boat, diagnose your boat, or any other boat by this info provided ... make sure you use the services of a qualified marine electrician familiar with DC and AC wiring in a marine environment.

 

[dcunniff]

Yes Dale.

As I said ground to ground.

For those that like to look at their 12V wiring, could be black or yellow ground. I have both. I've added some myself, black and yellow.

110V ground (green) to boat's 12V ground (chosen and verified, whether black or yellow, or some other color a do-it-yourselfer chose). I've seen red for 12V power and ground.

While I"m at it, you can find black and red 12V power on mine. In-line fuse holders sometimes have black wire as an example.

Dana

 

[gerg]

Btw, tying earth ground and your 12v neg together is an absolute no-no. You are begging for a galvonic problem. Thats what isolators are for.

 

[dcunniff]

Gerg, my shore power was installed by a dealer. I have a Newmar isolator I'm going to install.

Capt. Ronnie, I took some picture today of the shorepower setup.

Dana

 

[dcunniff]

Here's a paragraph on AC and DC wiring tied together and a description of galvanic action, from P&G Web Consulting.

Galvanic activity normally restricted to one boat can extend to affect other boats via the AC green grounding wire when ever two or more boats are plugged into shore-power. This is because the boat ground (including the bonding wire) and the AC green wire are connected together at a "common ground point" (often the engine), completing a circuit between multiple boats. Typically, the galvanic current passes from one boat's underwater fittings through a bonding wire inside the boat, onto the common ground point, onto the AC green wire that passes out to the shorepower chord to the dock pedestal, onto another boat's pedestal, power chord, boat, common ground, bonding wire, fitting, and then back through the water to complete the circuit. The boat with the least noble metal among the different boats will always protect the others (see figure 2).

Here's info from Marineco about an AC electrical guide. http://www.marinco.com/docs/guides/Boat ... trical.pdf. Note that if you have a problem with an AC ground on a boat and you aren't connected to the boat's DC ground you can be zapped.

Note on pg 19 for a standard 110V AC shorepower system an isolator is optional. I added my Newmar galvanic isolator today.

Here are some photos of it (cutting the AC green wire and running it in and out of the isolator and then up to the breaker panel).

Dana

 

[gerg]

Kewl, but as a practical matter, if you have a galvanic isolator installed, you haven't tied the two ground systems together. The wording implies you just spliced the lines together, and that would be a mistake.

You didn't do that, someone might have read it that way though.

 

[dcunniff]

Sorry, very good correction as it is so easy to read and take something wrong. The isolator lets a trickle flow through, lower than the typical voltage from galvanic action. Here's another good paragraph from the same prior article on the fundamental issue from having the benefit of having shorepower.

As more and more boats plugged into shore-power at crowded marinas, the problem became more common. There must be a connection... Actually, there is-the AC green grounding wire. Whenever you plug your boat into shore-power at a marina, you connect your boat to every other boat plugged into that pier via the green wire. That means your boat's underwater metal hardware is at risk, as is your neighbors', to the corrosive effects of galvanic current as it passes between two or more boats linked by the green wire, like an invisible trespasser. Invisible, that is, until you notice your aluminum sterndrive or some other metal fitting is looking a bit funky.

Here are three paragraphs that summarize how the isolator works and why they deliver benefit.

Galvanic isolators connect to the green wire, close to the shore-power inlet. Simply put, isolators block the circuit of galvanic current flow between neighboring boats. Isolators contain diodes, which are like valves whose inherent resistance blocks the low DC voltage generated by galvanic activity (up to 1.0 volt), but which conduct higher voltages exceeding the initial resistance. The idea is that your boat becomes isolated from passing or receiving low-voltage galvanic current between neighboring boats while still being able to pass dangerous AC voltage through the green wire to the shore ground.

The most efficient isolators have a capacitor, which allows low levels of only AC current to immediately bypass the diodes to the shore ground-an important feature, since stray AC current is more common than not. Considering that marina wiring is often less than ideal, and that as little as 5 milliamps of stray AC current can imperil a swimmer, it makes sense to immediately pass as much stray AC current through the isolator to shore ground as possible before the stray current seeks alternative parallel paths to ground through the water.

In addition, without a capacitor to immediately bleed-off low levels of stray AC current, stray AC voltage and galvanic DC voltages can together add up enough voltage to easily drive the diodes to conduct, leaving the boat unprotected without the owner knowing it.

I'm on a small set of slips, about 36 boats on one long line of boats on each side in shallow harbor water with a brook dumping in and out with the tide.

Thanks for making the good point so others interested in shorepower understand the ground AC connection.

Dana

 

[Capt. Ronnie]

Here's a paragraph on AC and DC wiring tied together and a description of galvanic action, from P&G Web Consulting.

Galvanic activity normally restricted to one boat can extend to affect other boats via the AC green grounding wire when ever two or more boats are plugged into shore-power. This is because the boat ground (including the bonding wire) and the AC green wire are connected together at a "common ground point" (often the engine), completing a circuit between multiple boats. Typically, the galvanic current passes from one boat's underwater fittings through a bonding wire inside the boat, onto the common ground point, onto the AC green wire that passes out to the shorepower chord to the dock pedestal, onto another boat's pedestal, power chord, boat, common ground, bonding wire, fitting, and then back through the water to complete the circuit. The boat with the least noble metal among the different boats will always protect the others (see figure 2).

Here's info from Marineco about an AC electrical guide. http://www.marinco.com/docs/guides/Boat ... trical.pdf. Note that if you have a problem with an AC ground on a boat and you aren't connected to the boat's DC ground you can be zapped.

Note on pg 19 for a standard 110V AC shorepower system an isolator is optional. I added my Newmar galvanic isolator today.

Here are some photos of it (cutting the AC green wire and running it in and out of the isolator and then up to the breaker panel).

Dana

Any chance you can share where to get the best deal on that isolator ?

 

[dcunniff]

Capt. Ronnie, I didn't research it hard on price.

I ordered it from Consumer Marine Electronics for the first time. They are in NJ. I got it in about 3 days. I paid $149 plus $6 shipping. This was for the 30 amp model, GI-30. Consumer Marine's website is www.consumersmarine.com.

West Marine carries the more expensive Guest models. They are ignition protected and can be hooked up to an optional display.

Dana

 

[Capt. Ronnie]

Capt. Ronnie, I didn't research it hard on price.

I ordered it from Consumer Marine Electronics for the first time. They are in NJ. I got it in about 3 days. I paid $149 plus $6 shipping. This was for the 30 amp model, GI-30. Consumer Marine's website is www.consumersmarine.com.

West Marine carries the more expensive Guest models. They are ignition protected and can be hooked up to an optional display.

Dana

Thanks

 

[Bryan 2530]

I'm looking to install shore power and found this post and was wondering if anyone wanted to supply more pictures and tips from their install or factory installs. Thanks in advance.

Great pics Dana.

 

[dcunniff]

Here is a wider side view of the 110V panel. You can see the backside wire view in earlier posting.

Small bolts showing below are the mount for the galvanic isolator.

The shorepower connection through the cabin has connectors marked for the 110V wire colors. The 110V wiring goes to the 110V panel. You then use as many breakers as you want and run circuits. I only have one other than the charger.

The 110 V inlet is to a double breaker for 30 amp inlet. The 110V panel is grounded into the 12 volt common black or yellow 12 V wires.

What photos are you interested in.

As I noted earlier I had a dealer do it as quiet winter work.

Dana

 

[Bryan 2530]

Thanks for that photo.

What photos are you interested in.

Not sure yet. I'll also do it as winter work, just preparing right now. I have my stereo mouted where your distribution panel is so I might need to re config some stuff or find an alternative location, also I was planning on mounting the 30amp plug in the cockpit in the starboard side cutout so it is out of the weather and the cord can hang there if I want to. Not to keen on the plug on the side of the pilot house. I'm sure it works well and makes the wiring a little easier but I like to keep things out of site as much as possible. Do you see any problems with my plan yet? Thanks for the input.

 

[dcunniff]

Bryan, plenty of boats have the shorepower in the cockpit. Just have a longer run to a panel and a good wall or framework to mount it on.

For the distribution panel, you decide how many 110V breakers you want. Maybe you'll have to mount it in its own panel? The other thing you could do is move your stereo.

Here's a better view of the ground wire in and out of my galvanic isolator.

Also some other photos of back of distribution panel and another one of the battery charger.

Dana

 

[Bryan 2530]

Thanks!!!!

Always good to see the job done before I actually do it.
Looking at those pictures is like being inside my boat. Almost identical.