Shore Power Ground ??'s

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Bill

Shore Power Ground ??'s

Post by Bill »

Hello to all

I need help (boat that is, Im beyound help otherwise).

I have installed shore power on Rhapsody. Unused as yet! I did not ground the AC curcuit to the engine or anywhere other than the ground that comes aboard via the shore power cord from dockside!!

I have had several people tell me I need to ground it to the engine and several people who say I dont.

Ungrounded, it is my understanding that I have no electrollsys (sp) concerns, but may have death concerns!!!!

Grounded, they say I have no personal/boat risk, but do have electrollsys (sp) concerns.

One gentleman even quoted the ABYC (in support of not grounding to engine) standards to me, but the CD owners manual clearly shows a ground to the engine.

WHAT TO DO??????

Bill



cd25d@clnk.com
Bill

Re: Shore Power Ground ??'s

Post by Bill »

West Marine Product Advisor states "DO NOT" Ground AC curcuit to engine or anywhere else on boat. Stated that Santa Cruz Harbor has ordiance against ground to boat.

Why does CD manual show otherwise?
BS

Bill wrote: Hello to all

I need help (boat that is, Im beyound help otherwise).

I have installed shore power on Rhapsody. Unused as yet! I did not ground the AC curcuit to the engine or anywhere other than the ground that comes aboard via the shore power cord from dockside!!

I have had several people tell me I need to ground it to the engine and several people who say I dont.

Ungrounded, it is my understanding that I have no electrollsys (sp) concerns, but may have death concerns!!!!

Grounded, they say I have no personal/boat risk, but do have electrollsys (sp) concerns.

One gentleman even quoted the ABYC (in support of not grounding to engine) standards to me, but the CD owners manual clearly shows a ground to the engine.

WHAT TO DO??????

Bill


cd25d@clnk.com
D. Stump, Hanalei

Re: Shore Power Ground ??'s

Post by D. Stump, Hanalei »

Bill,
I just finished wiring shore power into Hanalei. The system has a #10 green insulated wire from the green bus in the panel to the engine common ground. I choose life protection over any electrolysis concerns. I will NEVER leave shorepower connected when I am not aboard the vessel, hence no electolysis concerns. There is no reason to do that! The point is, you do not want the 1st. Mate to get between the 120v. hot lead and ships ground without the circuit protection of either a GFCI or a circuit breaker, the hazard in my opinion is to great. So, by all means, ground the green bus to the ships ground!

Dave Stump
Captain commanding
s/v Hanalei CD-30
Bill

Re: Shore Power Ground ??'s

Post by Bill »

DAve

This is a 25D i am talking about and the curcuit is VERY Basic (one outlet period). There is a run of 6' to the 30 amp main breaker and a run of 3' to the single outlet which is GFCI and that is the entire curcuit. I may at some later date come off of the GFCI to an additional outlet in the head but dont envision anything else.

Since I sail year round, I use shore power in the winter for freeze protection with backup from a liveaboard in the next slip over. I DO NOT want to deal with electrolysis, but more importantly, I dont like the idea of 1st mate frick-a-see (sp way off) either.

BTW, why would ABYC standards (as conveyed by WM Product advisor) not call for grounding???

I am sooo confused!!!

Bill
D. Stump, Hanalei wrote: Bill,
I just finished wiring shore power into Hanalei. The system has a #10 green insulated wire from the green bus in the panel to the engine common ground. I choose life protection over any electrolysis concerns. I will NEVER leave shorepower connected when I am not aboard the vessel, hence no electolysis concerns. There is no reason to do that! The point is, you do not want the 1st. Mate to get between the 120v. hot lead and ships ground without the circuit protection of either a GFCI or a circuit breaker, the hazard in my opinion is to great. So, by all means, ground the green bus to the ships ground!

Dave Stump
Captain commanding
s/v Hanalei CD-30


cd25d@clnk.com
Larry DeMers

Re: Shore Power Ground ??'s

Post by Larry DeMers »

Hi Guys,

I also leave shore power plugged in all week long while we are gone. There is no reason *not* to, and plenty good reasons to do it..like if you spring a leak, the battery will only provide 60-70 AH of useable power to the bilge pump, so you better have that charger running in the background to power the pump until someone detects the problem and get me up there. Additionally, I am installing refrigeration now, and that will be on a timer to get the box down to temp before we arrive Friday evenings. The battery charger is providing the power to that also.

On our boat, the dockside power green wire is brought in to the AC distribution panel, and to the GFI outlets (2), and to the battery charger frame safety ground connection. That is all..I do not connect to the engine. Our electrical wiring is GFI protected, as intended, and we have no problems with electrolysis or shock.
The confusion on this standard even extends to the experts like Nigel Calder, who is in opposition to the ABYC, who is in opposition to the NYFA standard etc..so do not let someone say that there is only one way to look at this topic..there are two valid ways to view it, and two valid ways to meet the specs.

The reason that I do not ground the engine also, is that we visitmany different marinas during the year, and I am not sure about the wiring at any but the one we rent (which I have tested). I would rather have my boat ground create it's own ground through the bonding system, and leave the AC system have it's own ground through the dock power sytem. That way, our AC system is protected by the source provided safety ground. The DC system is bonded to all metal parts, and is grounded to the engine and other underwater parts. The two grounds are separate, and this is done all the time in industry. AC and DC grounds are hardly ever combined in commercial gear.

Larry Demers
s/v DeLaMer
Cape Dory 30

Bill wrote: DAve

This is a 25D i am talking about and the curcuit is VERY Basic (one outlet period). There is a run of 6' to the 30 amp main breaker and a run of 3' to the single outlet which is GFCI and that is the entire curcuit. I may at some later date come off of the GFCI to an additional outlet in the head but dont envision anything else.

Since I sail year round, I use shore power in the winter for freeze protection with backup from a liveaboard in the next slip over. I DO NOT want to deal with electrolysis, but more importantly, I dont like the idea of 1st mate frick-a-see (sp way off) either.

BTW, why would ABYC standards (as conveyed by WM Product advisor) not call for grounding???

I am sooo confused!!!

Bill
D. Stump, Hanalei wrote: Bill,
I just finished wiring shore power into Hanalei. The system has a #10 green insulated wire from the green bus in the panel to the engine common ground. I choose life protection over any electrolysis concerns. I will NEVER leave shorepower connected when I am not aboard the vessel, hence no electolysis concerns. There is no reason to do that! The point is, you do not want the 1st. Mate to get between the 120v. hot lead and ships ground without the circuit protection of either a GFCI or a circuit breaker, the hazard in my opinion is to great. So, by all means, ground the green bus to the ships ground!

Dave Stump
Captain commanding
s/v Hanalei CD-30


demers@sgi.com
Bill

Re: Shore Power Ground ??'s

Post by Bill »

Larry

The curcuit you describe (minus the batt charger) is what I have and the WM guy stated if you have a charger to ground as you have!

I dont believe that I will ground to engine!

Bill
Larry DeMers wrote:
Hi Guys,

I also leave shore power plugged in all week long while we are gone. There is no reason *not* to, and plenty good reasons to do it..like if you spring a leak, the battery will only provide 60-70 AH of useable power to the bilge pump, so you better have that charger running in the background to power the pump until someone detects the problem and get me up there. Additionally, I am installing refrigeration now, and that will be on a timer to get the box down to temp before we arrive Friday evenings. The battery charger is providing the power to that also.

On our boat, the dockside power green wire is brought in to the AC distribution panel, and to the GFI outlets (2), and to the battery charger frame safety ground connection. That is all..I do not connect to the engine. Our electrical wiring is GFI protected, as intended, and we have no problems with electrolysis or shock.
The confusion on this standard even extends to the experts like Nigel Calder, who is in opposition to the ABYC, who is in opposition to the NYFA standard etc..so do not let someone say that there is only one way to look at this topic..there are two valid ways to view it, and two valid ways to meet the specs.

The reason that I do not ground the engine also, is that we visitmany different marinas during the year, and I am not sure about the wiring at any but the one we rent (which I have tested). I would rather have my boat ground create it's own ground through the bonding system, and leave the AC system have it's own ground through the dock power sytem. That way, our AC system is protected by the source provided safety ground. The DC system is bonded to all metal parts, and is grounded to the engine and other underwater parts. The two grounds are separate, and this is done all the time in industry. AC and DC grounds are hardly ever combined in commercial gear.

Larry Demers
s/v DeLaMer
Cape Dory 30

Bill wrote: DAve

This is a 25D i am talking about and the curcuit is VERY Basic (one outlet period). There is a run of 6' to the 30 amp main breaker and a run of 3' to the single outlet which is GFCI and that is the entire curcuit. I may at some later date come off of the GFCI to an additional outlet in the head but dont envision anything else.

Since I sail year round, I use shore power in the winter for freeze protection with backup from a liveaboard in the next slip over. I DO NOT want to deal with electrolysis, but more importantly, I dont like the idea of 1st mate frick-a-see (sp way off) either.

BTW, why would ABYC standards (as conveyed by WM Product advisor) not call for grounding???

I am sooo confused!!!

Bill
D. Stump, Hanalei wrote: Bill,
I just finished wiring shore power into Hanalei. The system has a #10 green insulated wire from the green bus in the panel to the engine common ground. I choose life protection over any electrolysis concerns. I will NEVER leave shorepower connected when I am not aboard the vessel, hence no electolysis concerns. There is no reason to do that! The point is, you do not want the 1st. Mate to get between the 120v. hot lead and ships ground without the circuit protection of either a GFCI or a circuit breaker, the hazard in my opinion is to great. So, by all means, ground the green bus to the ships ground!

Dave Stump
Captain commanding
s/v Hanalei CD-30


cd25d@clnk.com
D. Stump, Hanalei

Re: Now I'm confused....

Post by D. Stump, Hanalei »

Larry & Bill,

Good discussion! The only reason I can see for connecting to ships ground is that if the dockyard ground is broken, you have no safety ground! I looked at my 120v needs also, a water heater, and 3 outlets and maybe a battery charger in the future. If you ran a good heavy 3 wire extension cord to these items, you would not have a ground to the engine, so why do some say to ground the panel to the ships ground? The only reason I can figure is if the dockyard ground is deffective.

Larry, your point about the bilge pump is good. I think you read awhile ago here that Hanalei suffered an open head seacock incident that an automatic bilge pump would have saved. Unfortunately, my bilge pump switch is broken, and I still haven't replaced it, so the standby capability of the 120v battery charger is a mote point. I only use the bilge pump with a manual switch. I guess anything can happen at sea or at the dock, but one thing I do do know is that now, before leaving the boat, everything is checked secure!

So, what DO we do? Ground to ships ground or not? Sure would like your opinions.....

Dave Stump
Captain Commanding
s/v Hanalei CD-30
Bill

Re: Now I'm confused.... I asked first (NM)

Post by Bill »

D. Stump, Hanalei wrote: Larry & Bill,

Good discussion! The only reason I can see for connecting to ships ground is that if the dockyard ground is broken, you have no safety ground! I looked at my 120v needs also, a water heater, and 3 outlets and maybe a battery charger in the future. If you ran a good heavy 3 wire extension cord to these items, you would not have a ground to the engine, so why do some say to ground the panel to the ships ground? The only reason I can figure is if the dockyard ground is deffective.

Larry, your point about the bilge pump is good. I think you read awhile ago here that Hanalei suffered an open head seacock incident that an automatic bilge pump would have saved. Unfortunately, my bilge pump switch is broken, and I still haven't replaced it, so the standby capability of the 120v battery charger is a mote point. I only use the bilge pump with a manual switch. I guess anything can happen at sea or at the dock, but one thing I do do know is that now, before leaving the boat, everything is checked secure!

So, what DO we do? Ground to ships ground or not? Sure would like your opinions.....

Dave Stump
Captain Commanding
s/v Hanalei CD-30


cd25d@clnk.com
Edd

Re: Shore Power Ground ??'s

Post by Edd »

Bill wrote: West Marine Product Advisor states "DO NOT" Ground AC curcuit to engine or anywhere else on boat. Stated that Santa Cruz Harbor has ordiance against ground to boat.

Why does CD manual show otherwise?
BS

Bill wrote: Hello to all

I need help (boat that is, Im beyound help otherwise).

I have installed shore power on Rhapsody. Unused as yet! I did not ground the AC curcuit to the engine or anywhere other than the ground that comes aboard via the shore power cord from dockside!!

I have had several people tell me I need to ground it to the engine and several people who say I dont.

Ungrounded, it is my understanding that I have no electrollsys (sp) concerns, but may have death concerns!!!!

Grounded, they say I have no personal/boat risk, but do have electrollsys (sp) concerns.

One gentleman even quoted the ABYC (in support of not grounding to engine) standards to me, but the CD owners manual clearly shows a ground to the engine.

WHAT TO DO??????

Bill
Now I am confused.

Our CD28 power has an obviously intentionally unattached green ground
shorepower wire dangling uninsulated and extremely close to the ships grounding bar in the electrical "cabnet". I have wondered why, but believe (since everything is working okay)I should let it be. Do you agree?
Edd



Erogers711@AOL.com
Bill

Re: Shore Power Ground ??'s

Post by Bill »

Edd

I dont have that much experience in this area, so dont even ask me (sorry)! I have a quote from Don Casey's "This Old Boat" --- "Connect the green wire also to your boat's common groung point, usually a bolt on the engine to which the negative battery cable"

He goes one to say (paraphrased) that there are two problems with this process. 1. swimmers near the boat are in trouble in case of a short. not many swimmers in a marina. and 2. There is a likely hood of galvanic corrosion from stray currents from your own system or attracted from others.

AS I stated earlier according to P--- (a WM product advisor) Santa Cruz harbor forbids (by legistlation) the grounding of AC circuits (God what a dummy, I cannot even spell circuit --see earlier post---), and the ABYC does not consider it a standard (I know that may leave alot to be desired considering what that council consists of).

All this said I rarely have shore power, except in winter, and I dont want galvanic stuff going on, so Im not grounding to the engine.

Bill

Edd wrote:
Bill wrote: West Marine Product Advisor states "DO NOT" Ground AC curcuit to engine or anywhere else on boat. Stated that Santa Cruz Harbor has ordiance against ground to boat.

Why does CD manual show otherwise?
BS

Bill wrote: Hello to all

I need help (boat that is, Im beyound help otherwise).

I have installed shore power on Rhapsody. Unused as yet! I did not ground the AC curcuit to the engine or anywhere other than the ground that comes aboard via the shore power cord from dockside!!

I have had several people tell me I need to ground it to the engine and several people who say I dont.

Ungrounded, it is my understanding that I have no electrollsys (sp) concerns, but may have death concerns!!!!

Grounded, they say I have no personal/boat risk, but do have electrollsys (sp) concerns.

One gentleman even quoted the ABYC (in support of not grounding to engine) standards to me, but the CD owners manual clearly shows a ground to the engine.

WHAT TO DO??????

Bill
Now I am confused.

Our CD28 power has an obviously intentionally unattached green ground
shorepower wire dangling uninsulated and extremely close to the ships grounding bar in the electrical "cabnet". I have wondered why, but believe (since everything is working okay)I should let it be. Do you agree?
Edd


cd25d@clnk.com
M. R. Bober

You can't all be wrong!

Post by M. R. Bober »

I'm not an expert, but I have done a bit of reading on this subject, very recently. The AC ground probably should be connected to ship's ground. NEUTRAL MUST NOT BE CONNECTED TO SHIP'S GROUND!!!! Let neutral connect to shoreside neutral. Consider the prospect of connecting to a shore source with polarity reversed.

You may wish to install an isolation transformer, but that's a whole different call for opinions.

Look at it this way, galvanic corrosion can be repaired. Dead crew can't. Just an opinion.
M



thebobers@erols.com
Matt Cawthorne

Two more cents

Post by Matt Cawthorne »

Bill,
You certainly picked a controversial topic. The electrical ground has to be considered with many different scenarios in mind. For instance if you have a bad connection bewteen your green wire and the shore power earth ground and you connect the green wire to the engine then you can zap swimmers if an appliance goes bad. Having ground fault interupters is a good way to avoid hurting people.
The ABYC has put more thought into the electrical system then I ever will. I think that you have to join their organization to get a copy of their recommendations but I intend to do so as soon as I figure out how. For the moment I would suggest that you follow ALL of their recommendations and not just pick out a single piece like the proper use of the green wire in the AC system. The reason for this is that the grounding recommendation may have been made assuming that certian other precautions were taken to assure that the AC and DC systems never come in contact. Without those other precautions the grounding recommendation might not have been made.
If all you use the shore power system for is a single outlet why not just get an adapter for your shore power cord and plug into that without drilling any holes in your boat?

Good luck.
Matt


Bill wrote: Hello to all

I need help (boat that is, Im beyound help otherwise).

I have installed shore power on Rhapsody. Unused as yet! I did not ground the AC curcuit to the engine or anywhere other than the ground that comes aboard via the shore power cord from dockside!!

I have had several people tell me I need to ground it to the engine and several people who say I dont.

Ungrounded, it is my understanding that I have no electrollsys (sp) concerns, but may have death concerns!!!!

Grounded, they say I have no personal/boat risk, but do have electrollsys (sp) concerns.

One gentleman even quoted the ABYC (in support of not grounding to engine) standards to me, but the CD owners manual clearly shows a ground to the engine.

WHAT TO DO??????

Bill


mcawthor@bellatlantic.net
Larry DeMers

Re:Grounding and Bilge pumps Confusion

Post by Larry DeMers »

Dave and all,

In the case of a broken Dockyard ground, your system will operate as usual unless there is a shorting fault from either Line or Neutral to an external surface of a 120vac appliance that is plugged into your receptacles. This would put 120vac on the appliance's surface, which would normally be grounded through the dock service and would normally blow their breaker once too much current is drawn.

With the scenario of a broken ground at the dock, the poor person touching that shorted out appliance will have a jolt to deal with. Grounding to the engine ***WILL NOT STOP THIS**. What you will do is electrify the water through the boats grounding system. This then endangers that diver in the water next door, as the water near your boat is at a different potential than the water that he was in. This could kill him.

I prefer for the sake of coupling noise into the boat from the AC ground, and other reasons, not to ground that safety ground to anything but the charger frame (but *not* the negative output terminal) and your GFCI outlets. Now, you are protected from shock by the GFI outlet. It compares the current balance between the Line and Neutral to safety ground. If there is a short of either Line or Neutral to ground, it will interrupt. This is independant of the shore safety ground.

I hope this helps. There is a lot of confusion out there, and neither case is an absolute slam dunk..you're right! They both have positives and negatives..trouble is, you don't know about all of the negatives until after they have been working on you a bit.

Cheers All!!


Larry DeMers
s/v DeLaMer
Cape Dory 30



demers@sgi.com
Larry Demers

Re:Dave..Here's a solution for your bilge snsor

Post by Larry Demers »

Hi Dave,

Yup. read your account about the head running over. We have had this happen too..while aboard thank goodness.

I decided to put in an electric bilge pump (had none for 7 years..really stupid of me!), but did not like the idea of putting a water detection switch in the bilge, where things are occasionally rather messy. I found exactly what I was looking for. An externally mounted, inexpensive bilge water switch. It' s made by Groco, and is a rubber diaphram with a manually adjusted microswitch built into the sensor. The whole thing is enclosed in anodized aluminum. The principal operating theory is that there is a small plastic tube (similar to aquarium air line tubing) going down into the bilge. The end is connected to a small round bell-shaped part. This traps air in the tube. WHen the water rises more than 3 inches, it activates the microswitch (this turn on point and also the span between on-off are adjustable from the engine compartment), which turns on the pump motor. The sensor itself stays clean and dry, and the sensor is only 1 inch in diameter, so it can be mounted anywhere. Incidently, this is the same method used by the motor control companies to determine pump turn on/off points with sewage pits and lift stations.

These are available from West Marine and Defender for certai, and cost around $40.

Cheers!

Larry DeMers
s/v DeLaMer
Cape Dory 30
D. Stump, Hanalei wrote: Larry & Bill,


Larry, your point about the bilge pump is good. I think you read awhile ago here that Hanalei suffered an open head seacock incident that an automatic bilge pump would have saved. Unfortunately, my bilge pump switch is broken, and I still haven't replaced it, so the standby capability of the 120v battery charger is a mote point. I only use the bilge pump with a manual switch. I guess anything can happen at sea or at the dock, but one thing I do do know is that now, before leaving the boat, everything is checked secure!


demers@sgi.com
M. R. Bober

I can't stand it anymore!!!

Post by M. R. Bober »

I have posted a request for info about ABYC standards on the website of the National Electrical Resources Board (www.electrician.com GO TO THE BULLETIN BOARD). These guys know their stuff. Let's see what comes forth.
Regards to Matt.



thebobers@erols.com
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