Starting from Scratch

[GordMay]

Rick:
Ground Electrode Plate
I notice you’re contemplating the use of a “sintered” Guest 4006 Dynaplate (6" x 2").
Although 1 square foot is usually cited as a minimum ground plate size, you should be aware that fresh water usage requires larger electrodes than salt.
Most authorities recommend at least doubling the size in fresh water.
I don’t believe there is any functional improvement in utilizing a sintered material, over standard plate.
I would use the longest 2" - 4" wide copper strap (½" thick) practicable.

?
What's a "Demone" Battery?

[knottybuoyz]

Originally Posted by GordMay

Rick:
Ground Electrode Plate
I would use the longest 2" - 4" wide copper strap (½" thick) practicable.
What's a "Demone" Battery?

Thanks Gord, so I can go to the metal scrapper and pick up a big chunk of copper for the ground plate? Say 4"W X 12"L by 1/2" thick would work?

Demone is a brand name of battery that we find easier to get down this way. They're realitively in-expensive and I can get them shipped right to the marina for free. I'm still debating what battery technology to use. I'm sure things are gonna change between now and March '08.

[knottybuoyz]

Originally Posted by Rick

Do you have the ability to mount a large frame (9inch dia.) high output alternator in addition to the existing one?

Got word from the rep. The answer to this question is "Yes" up to 20 HP off the pulley's is acceptible.

Originally Posted by Rick

What is the stall current rating of your starter motor? This determines the selection of a fuse rating from the battery. I am opposed to the inclusion of a fuse between a start battery and the starter.

He didn't know what the stall current rating for the start is. I've removed the fuse from the conductor between the battery and starter in the latest revision of my drawing posted earlier. The length of cable from battery to switch to starter is about 48".

Rick

[knottybuoyz]

Moved some things around to clean up the wiring and make it easier to follow (I hope).

I think we're getting very close now. Waiting for Rick to toss me a curve ball with some fancy schmancy newfangled alternator thingy. We're also running very close to the limit of the budget on this part of the project. Back to the spreadsheets to do some number crunching. The ole' girl might have to work a few extra hours overtime eh?

[knottybuoyz]

Ok, going through ABYC E-11 and cross checking my work. Came across requirment under E-11.7.2.4 for the main shore power disconnect breaker. Silly question is this breaker the one in the AC distribution panel or is it external to the panel? See diagram which seems to infer it's exterior. It has to be a "simultaneous trip" circuit breaker to disconnect the shore grounded (white) conductor and the shore ungrounded conductor (black).

If it's the breaker in the AC distribution panel then it would infer that the Isolation Transformer is on the downward leg of AC distribtion to the panel. Or you simply loop the AC feed from the panel through the Isolation Transformer then back into the panel?

[Auspicious]

Rick,

I think you have been getting quite a bit of very good advice. With all due respect to Paul, I'd like to offer an alternative to his suggestion for battery switching. I suggest three one/off battery switches. One between your house bank and house loads, one between your start battery and the starter, and one between the house circuit and the starter circuit (on the load side of the other switches). This approach gives you maximum flexibility.

I'd also encourage you to stay with one house bank as big as you can possibly make it. Splitting your house batteries into two banks adds to maintenance and complexity without a meaningful improvement in any area.

[knottybuoyz]

Thanks Auspicious. I think I get the same switching options with the 9200E between the house and starting bank. At least to my tired eyes the possibilities seem the same. I think I've looked at this too much and it's time to put it down for awhile.

Latest update: redrew the AC/DC distribution panel in detail. Have yet to map out the individual connections to loads and spec the breakers.

From what I can figure out the main shore power disconnect will have to be a breaker upline from the Isolation Transformer. There's no way to get unprotected AC into the panel then loop it through the transformer then back into the panel. Anywho, have a look. Thoughts, suggestions etc. are always welcome.

Rick

[DeepFrz]

Yes, I agree. It is best to have your main shore power cct. breaker as close to the shore power connector as possible, then to the isolation transformer and then to the distribution panel

Looking good.

[GordMay]

All good advice.

E-11.12.2.4 calls for overcurrent protection in the primary conductors of a transformer.
This would require a 2-pole breaker between the shore power inlet and the isolation transformer primary (as indicated on diagram 6).

I know you (Rick) have access to ABYC Standards, but for others that don’t:

ABYC Standrard “E-11" (AC & DC Electrical Systems on Boats)
http://www.abycinc.org/committees/e-11.pdf

[knottybuoyz]

Wow, working on this laptop w/piss poor video capabilities sure slows down editing big graphic files. I don't have Adobe writer here so I had to toss the drawing from Visio to AutoCad and PDF it online with their free tool. AutoCad mixes a few things up and messed up the page formatting but I'll correct that on Monday.

Anyhow, I inserted the circuit breaker on the main AC feed as discussed. Drew in the major loads and indexed each to their appropriate breaker on the panel. A few more doodles and that's all I can do today.

Thanks for the input fellas. I appreciate your time and expertise.

Rick

[knottybuoyz]

Better PDF file this time. It helps to have the right software tools!

[knottybuoyz]

This will be the last revision unless you think there's really need for a change. The engine rep replied that min rating for a starting battery is 650 Amps which I've exceeded and that they recommend 2/0 to the starter if the battery is less than 10' from the starter, which it will be so I've adjusted those specs accordingly.

It's been a great exercise fella's, I've learned a lot and think we've really got something to work with now. Thanks.

[DeepFrz]

Rick, just a nit. You have labeled part of the 2/0 cable run to your thruster. One of the vertical segments has a #6 beside it.

Looks great, it's been fun following along.
Cheers,
Deep

[knottybuoyz]

With regards to a boats bonding system, are the wires from metal thru-hulls to a common bonding strip solid or stranded conductor? I'm being told (other bbs) by an obviously knowledgeable, experienced and reputable boat guy that anybody considering using stranded conductors in the bonding system would be an "idiot". For the life of me I can't figure out why, but anyways.

I have seen photos of thru-hulls bonded with solid conductors but can't find a specific reference or requirement for such in either the ABYC standards, Transport Canada standard for Small Vessel Construction or in Nigel Calder's book.

So, can anybody point me to a definitive reference as to which type of conductor is used in the bonding of metal thru-hulls? I'm thinking it's an industry standard practice that hasn't made it into the standards yet.

[Extemporaneous]

Originally Posted by knottybuoyz

Again some research turns up the Charles Industries Iso-Guard 93-IXFMR3/6N-A 3.6 kVA (30 amps) Isolation Transformer which seems to be just the ticket. A good choice? About twice the cost of a galvanic isolator. I can't seem to put my finger on pricing for the Mastervolt equivalent.
I do greatly appreciate your help!
Rick

I know this is an old thread but was wondering if anyone has any comments on the the two three (add: CHARLES 3.8KVA 30 AMP 120/240VAC 50/60HZ ISO-GUAR - 93-IXFMR3/8NI-A) Isolation Transformers?
Further to that with regard to the MasterVolt product, I can't seam to find a place to purchase. Does anyone know where I could (in Canada but US online would be fine) get pricing/purchase it?

Any help would be great, Thanks.
Extemp.