Electrical Grounding Wire - E28+

[Dan Hayes]

While cleaning out the raw water strainer on my boat yesterday, I moved the green grounding wire (coming out of the shore power box) out of the way. Much to my surprise, the wire was not attached to the engine. The connector was still good, but there the wire was, not attached.

I don't know if the P.O. had removed it, or a thoughtless mechanic had unhooked it for some reason, but I have no idea where it should go.

Does anyone know exactly where this wire should hook up? I figure it should be bolted to the engine, but I don't want to start pulling just any bolt out to attach it.

Suggestions greatly appreciated.

Thanks,

Dan Hayes

 

[bwindrope]

same problem

Hi Dan,
I am still fixing up my 28+ from having purchased it just a few months ago and am very happy with my progress so far. It turns out I have exactly the same problem with my grounding wire and haven't wanted to touch it either.

By the way, my new aluminum fuel tank from RDS in Florida is supposed to arrive next week and I can't wait to install it and transform my boat experience from a nerve and odor wrecking gauntlet to one of near carefree certainty.

Let's hope someone has an answer.

 

[diamondjim]

AC Grounding

Hi Dan,
I was just inside my AC panel chasing after my hot water heater connections. I'm sure the grounding wire (green) is connected to the box and not the engine! The exact connection I am trying to remember because I was not paying attention to that detail. If there is not a satisfactory answer posted in the next few days (I am not at my Bay house), I will get back to you on my connection - it is correct. I also have the original wiring diagram and will check for sure. Your 12 Volt ground wiring is connected to the engine and is usually black.
<> Jim

 

[rssailor]

Bonding

Well you need to put this wire onto the engine block. If you are pluged in, all the time you might want to consider putting in a galvanic isolator with a monitor. What kind of engine is on this boat? Ryan

 

[hcpookie]

Well you need to put this wire onto the engine block. If you are pluged in, all the time you might want to consider putting in a galvanic isolator with a monitor. What kind of engine is on this boat? Ryan

Interesting... I've read here (in this forum) and elsewhere that you do NOT put it on the block and keep it completely isolated from 12v stuff. I think the reasons given were to save hassle w/galvanic issues or possible grounding issues, but I forget the details now.

This is just normal 110v house wiring... right? If yours is a standard 110v 2-wire system, then the green could theoretically stay unconnected since it wouldn't serve any purpose unless a 3-wire outlet (like a GFCI) were installed.

The E27/29 section in the Specs & Documents has the shore power wiring diagram - the diagram shows that the AC power is isolated from the 12v system. I don't see a similar doc for the -28. Are the -27 and -28 similar enough that this doc applies?

When I put a GFCI in my -27, I was surprised at how un-complicated the AC power system turned out to be - just a few plugs and that's it. Just standard outlets all on one circuit.

Be careful when you play around with the 110v wires so that you don't disturb the aged insulation - some could fall away and expose wires if you happen to jostle them around too much. Case in point - behind the panels, the insulation on my wires are REALLY BAD when I installed the GFCI. Flexing the wires would expose bare wire behind the aged insulation. Not a good thing, since window leaks can puddle around the wires (at least on my -27). I plan to replace all the 110 wire with some brand new stuff next winter, but until then I'm extra careful to be sure I don't move the 110v wire too much. Just FYI - hopefully you won't have to fiddle around with yours as much as I did!

Be careful! Electricity and water always makes me nervous.

Edit to add, you could probably get a quick answer from a surveyor if you phoned them... the few I've talked to always have some good information to share!

 

[Mike.Gritten]

Anyone working on their AC system on their boat should exercise EXTREME caution. The potential to create a system where YOU are the best path to ground and are therefore electrocuted is high! Read Nigel Calders book and then make your AC design decisions.
Not being an expert, and certainly wanting to avoid any future litigation, take my opinions as just that, my opinion.
There are two schools of thought with AC grounding -

1) Create a Common Ground Point and ensure that all your DC grounds are bonded to this CGP. Make sure that your AC green wire from shore power and your panel(s) all are securely bonded to that same CGP.

2) Maintain electrically isolated AC and DC electrical and grounding systems.


We have chosen to follow recommendation #1 since it is very difficult to isolate and ground both systems and there are inherent safety benefits with this system since the AC is effectively bonded to sea water (electrical ground in a boat) and should be the best path to ground in case of a short circuit. We have installed a new Blue Seas AC panel with a choice of running the AC system from shorepower or from our inverter (only one source at a time via a safety lockout on the panel). All our AC receptacles are ground fault protected. We have a galvanic isolator where the shorepower enters the boat. We feel very safe!

 

[rssailor]

Green wire

Mike,
Yes of course make sure you turn off the AC or even better yet unplug the boat before working on any AC wiring.

Ok, now on a "properly" wired boat, the green wire will go to the Engine Block. Yes of course there should be a cable from the engine block to the DC negative battery or buss bar. This SHOULD BE THE ONLY POINT on the the boat that the AC and DC meet. Preferably there should be a buss bar where all the bonding wires go and one wire from there connects to the shaft or wherever the zinc is. There are lots of schools of thought on bonding or not to bond. Yes Nigel Calder writes some interesting stuff on bonding.
Just a little background, I have been a marine electrician for eight years now and have seen several cases where boats had a bonding system that was broken or non existent and had problems with electrolsis. Ok with that said, do what you think is right, but your green wire from the panel really should be conncted to the engine block, preferably on one of the transmission bolts on the aft end of the engine. Ryan

 

[Dan Hayes]

The Green Wire To Nowhere...

OK, thanks for the info, guys. I am going to see if there is a loose bolt somewhere, or if I can remove a bolt from the transmission to make the connection. It's a pretty long wire - like four feet long. I can't believe someone would leave it unhooked - just doesn't make sense to me.

I was looking at installing a "zinc saver" type galvanic isolator, but the whole 110V thing gives me the heebie jeebies. I think I can handle ground fault interupting AC receptacles (one of the projects on the list, and recommended in my last survey) but opening and messing with the AC box is not high on my list.

Again, thanks to all for the input, I really appreciate it.

-Dan Hayes

 

[hcpookie]

Anyone working on their AC system on their boat should exercise EXTREME caution. The potential to create a system where YOU are the best path to ground and are therefore electrocuted is high! Read Nigel Calders book and then make your AC design decisions.
Not being an expert, and certainly wanting to avoid any future litigation, take my opinions as just that, my opinion.
There are two schools of thought with AC grounding -

1) Create a Common Ground Point and ensure that all your DC grounds are bonded to this CGP. Make sure that your AC green wire from shore power and your panel(s) all are securely bonded to that same CGP.

2) Maintain electrically isolated AC and DC electrical and grounding systems.


We have chosen to follow recommendation #1 since it is very difficult to isolate and ground both systems and there are inherent safety benefits with this system since the AC is effectively bonded to sea water (electrical ground in a boat) and should be the best path to ground in case of a short circuit. We have installed a new Blue Seas AC panel with a choice of running the AC system from shorepower or from our inverter (only one source at a time via a safety lockout on the panel). All our AC receptacles are ground fault protected. We have a galvanic isolator where the shorepower enters the boat. We feel very safe!

Great info! What kind of galvanic isolator are you using?

 

[Loren Beach]

"Zinc Saver" questions

We are in fresh water here, unless and until we go cruising up to the Puget Sound area in the summer. My zincs normally last 3 years between bottom painting haulouts.

I am about to haul and paint, and am now comtemplating adding a ProMariner Zinc Saver to the AC system. The plan is to (finally!) take the boat north next summer and this will see us using a variety of public and YC marinas, some with dubious wiring and all of them in salt water.

From helpful comments in other threads on this site I deduce that a galvanic isolator (i.e. "zinc saver") would be a wise addition to our boat.

Since this device goes between the AC green wire and the boat's ground point (engine block?), would I just install it behind the AC distribution panel and run a #10 green wire from the device to the engine block?

A techie at our local marine electronics store tells me that this will cost me about $160. and that, based on my previous DIY electrical work experiences, should be easy for me to install.

Thanks,
Loren in PDX
Olson 34 #8

 

[hodo]

On my 30+, the green wire was the bonding wire, tieing the bronze through -hulls together.It was attached to the block, but I removed it and found my zincs lasted longer, and the 2 new through hulls did not go red. harold

 

[Howard Keiper]

The appropriate standard is ABYC, E-11 (used to be E-8) which dictates that the green grounding wire must be connected to the engine ground or it's buss.
Further, the ONLY device allowed to be connected in series with that wire is the Galvanic Isolator...no switches, nothing.

howard keiper

 

[Howard Keiper]

A 30 amp GA should cost around $100-$120 on e-bay.

I rescued a C&C 36 recently in which the owner previous to the guy in trouble decided that it would make good sense to connect, or bond the green wire to something metallic in contact with the water. The handiest thing(s) he could get his hands on were two of the bronze through hulls in the head. He came very, very close to losing his boat.

 

[Howard Keiper]

One of these days I'm going to learn to read my posts before I send.

GA, of course, should be GI, my shorthand for Galvanic Isolator.

I wonder wha a GA really might be? at only $100, it's a steal... )

howard keiper

 

[Howard Keiper]

A really easy (and thorough) read on the subject is a West Marine Advisory, itself a reprint from a Practical Sailor, published in 1998.
http://www.westmarine.com/webapp/wcs/stores/servlet/westadvisor/10001/-1/10001/groundingsystems.htm

howard keiper

 

[rssailor]

Galvanic isolator

Loren,
If your going to go to the trouble of putting a Galvanic isolator in, get on that meeting the ABYC spec with monitoring of the AC neutral and ground wires. Do not waste your money on a non ABYC compliant unit. Ryan

 

[Loren Beach]

Doing it "right"

Ryan,
Thanks for the straightforward logic. I had been thinking about that, too.
The installation really should be ABYC compliant, or a future survey would flunk it anyway.

I looked up prices at the Defender site, and there is quite a wide range of $$ for these devices, from different makers.
I can only wonder which one is the best engineering bang for the proverbial buck...
I mean, some are two and three times the price of others.

After listening to the ABYC rep at our recent YC meeting, I can see that dealing with AC means minimizing risk to: 1) the occupants of the boat, and also 2) to any swimmer in the water near the boat. This particular guy is quite intense about protecting people inside and outside because his own small son was killed by stray current while swimming beside another boat six years ago. He then started his boat electic business and decided to become educated in ABYC and safety issues. His sincerity and credibility really came accross to us all.

So now my goal is to find a reasonable way to protect people inside or outside of the hull and also "save" our zincs.

All these boat projects just seem to grow in complexity and extenuating circumstance the more you research them... :thinker:

Take care,

Loren in PDX

 

[Tom Metzger]

Loren - Did the rep explain how his son got in trouble?

 

[CaptnNero]

Loren - Did the rep explain how his son got in trouble?

This was written up recently but I don't remember where, perhaps BoatUS magazine. The kids were swimming in the water next to the slip. The one son separated from the others, gasped, and stopped moving. The mother jumped in and felt numb as she tried to approach him. Then she eventually reached him and with help pulled him from the water. She said that she felt paralyzed by the trauma of the situation while in the water.

The boy was dead, couldn't be revived, and the hospital and authorities initially wrote it off as a drowning. But the parents soon realized that something was amiss. So the father took an electrician back the next day and using a voltmeter was able to isolate electrical current in the water to a nearby boat with a faulty charger. Then the authorities finally listened, got involved and learned something. The numbness the mother felt in the water was the current that basically electrocuted the boy.

I was considering cleaning the prop this spring while in the slip for the first time until I read that story which happened about 1999. Since reading that we have motored away from the marina to dive the prop.

 

[Howard Keiper]

As I reviewed these threads I came to the conclusion that the disposition of the (in)famous 'green wire' is still the subject of debate, as is the efficacy of a galvanic isolator. The rules ae very clearly spelled out...what connects to what and how it connects. There is no ambiguity. For those without access to ABYC EII, a nice concise write-up on the subject can be found in the West Marine Advisor, www.westmarine.com >electrical >grounding systems. As I mentioned in a previous post, this is a reprint of an article from Practical Sailor, originally printed back in 1995 or sometime, by Stan Honey, a well known sailor, navigator, and engineer.
As for the Isolator, the current consensus IS correct, that is, it makes perfect sense to have one...it can save your life and your boat, and the particular devices that have status indicators, local or remote, and the latest joy, a capacitor, are so well priced that it makes no sense not to go that route. ABYC A-28 is the defining standard. Go with a reputable manufacturer and dealer and you can't go wrong. Once you've figured out what you want however, you might luck out and find the same thing on E-bay.
howard keiper