Shore power inlet for battery charger

El Borracho

Sam’s friend
6,434
2,452
Pacific Rim
I would prefer a charger that does not ground either battery lead. I don’t know why they would do that, but they might. Certainly not necessary for charging. Would seem to violate some electrical “best practices” regarding multiple power ground paths. However, maybe most charger instructions say to isolate the battery to charge. Which of course nobody ever does ever. 

 

Rain Man

Super Anarchist
7,033
1,947
Wet coast.
So, if using a drop cord, would you use the AC ground or not?
Yes.  But I would confirm that there is no continuity between the AC ground and the boat's DC ground, or more importantly any under water metals, which it seems you have done if I am reading your posts correctly.  Did I also read that the boat lives on the hard in the winter?  If so, then no worries at all.

 

George Dewey

Super Anarchist
2,071
118
Charleston, SC
The manual says:
"e) A marine (boat) battery must be removed and charged
on shore. To charge it on board requires equipment
specially designed for marine use."


https://www.victronenergy.com/upload/documents/Manual-Blue-Smart-IP67-Charger-120V-EN-FR-ES.pdf

So, there's that.

Can you check for continuity between the earth pin and the battery negative?
So, the ground prong on the 110VAC cord does not have any continuity to the negative battery terminal or the ground system on the boat.  

 

Quickstep192

Anarchist
739
133
Chesapeake
Yes.  But I would confirm that there is no continuity between the AC ground and the boat's DC ground, or more importantly any under water metals, which it seems you have done if I am reading your posts correctly.  Did I also read that the boat lives on the hard in the winter?  If so, then no worries at all.
On my charger, there is not continuity from the AC ground to the DC negative, BUT, there is a chassis ground that does have continuity to the AC ground. So, if I ground the chassis to the boat’s grounding system, then I’m effectively making a connection between the AC ground and the boat’s grounding system. 
 

The boat is kept on a lift so it’s out of the water unless the tide is super high. 

 

Rain Man

Super Anarchist
7,033
1,947
Wet coast.
On my charger, there is not continuity from the AC ground to the DC negative, BUT, there is a chassis ground that does have continuity to the AC ground. So, if I ground the chassis to the boat’s grounding system, then I’m effectively making a connection between the AC ground and the boat’s grounding system. 
 

The boat is kept on a lift so it’s out of the water unless the tide is super high. 
Why do you want to connect the chassis ground (presumably the chassis of the charger) to the boat's DC ground?  Does the manual for the charger suggest that?   If not, I would leave it connected to the AC ground only.  This will allow your DC system to float relative to the AC.  I can't see any problem with that, but this is getting beyond my expertise in maritime electronics.

 
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Startracker

Member
390
103
Van Isl.
The Victron isolators are not technically failsafe.  In talking with their techs, they do fail to a safe mode(ground circuit closed) but they didn't test with the required loads to meet ABYC standards(3000A, 34 cycles).  I'm comfortable enough with the Victron and regular testing with a meter at half the price of the competition.  Short of a lightning strike, I think I'll be alright.  Also as a sidenote, an isolator with a status monitor will also be ABYC compliant if it isn't fail-safe from my understanding of the wording in A-28.  



[SIZE=9pt]28.6 [/SIZE][SIZE=9pt]STATUS MONITORING[/SIZE]

[SIZE=9pt]28.6.1 The galvanic isolator shall be equipped with an integral or external status monitor that provides an audible or visible indication of failure.[/SIZE]

[SIZE=9pt]Exception: Fail-Safe galvanic isolators[/SIZE]




 

phillysailor

Super Anarchist
8,120
2,973
You drill a 3/8" diameter hole in the drop board very close to the top edge. Then saw down to the hole and remove the bit of wood or plastic...

This secret technique is what we in the industry call "a notch". I only offer this because I'm a nice guy. Don't spread this sort of secret around.

View attachment 473810


Well looky here! 
 

I devised a way to snake a 12ga cord around the drop board and still allow the hatch to fully close. I’m calling it the “No-Notch Shore Power Inlet” (Patent Pending)

View attachment 474588


Close enough to a notch. You owe me royalties dude.
@Zonker, your original description was of a method requiring the use of drills, saw & material removal, which you were altruistically offering because of a personality flaw called “being a nice guy.”

You are now trying to enforce patent rights upon the user of a product neither of you manufactured despite having previously offered said intellectual property without fee.

I am afraid the interwebs cannot tolerate such egregious false patent claims and award the defendant two free ideas. (Penalties waived given your many years of ridiculously valuable service to the community.)

Game on!

 
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