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Grounded to the engine block

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"In working on the rewiring th

"In working on the rewiring the batteries, I need some advice. The Promariner ProTech 1220i was wired for only two banks. The generator battery was in parallel with the starboard battery. In reading the direction from the battery installation manual, it suggests connecting all the negative cables from the batteries to a common ground. My boat apparently does not have a common ground. All the negative battery wires are connected to the engine blocks, along with the 8 AWG green bonding wires. The battery charger is also connected to the starboard engine block.
The Tiara manual’s wiring diagrams are scanned, the boat is still fairly original in the schematic.
Should I add a bus bar for all the negative wiring, as indicated as the preferred method from Promariner. What would be the best way to do this? I was thinking of running one cable from the block to the bus bar from each engine. Then I can attach the charger’s negative connection, and then one from each of the batteries. I am trying to set up four batteries, the house and generator in parallel.

Any advice is appreciated. I have been in contact with Promariner and I think this question is not going to be solved by talking with them. They did explain other questions for me because the manual was lacking in information."
 
"This is one way:
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"This is one way:
http://bluesea.com/category/9/35/productline/188

The pro for doing this is you have a common DC reference point. The con for doing it has a couple components. First is extra connections; they can go bad and then they add cost and weight.

If all your grounds go to the engine blocks and they are bonded together, you may be okay, as is. The grounding bar on the dc distribution panel, if used, should also be tied in to the block. Best way to determine your system's health is to measure the grounds and see if they have any significant voltage drop."
 
"Thanks. Electrical is somethi

"Thanks. Electrical is something I do not know much about. I did buy a bus bar today, a Blue Seas at West Marine it has four studs. I think leave it as is for now and get all 4 group 27's installed. Then I can change it later, I will most likely measure it before and after to see which is best."
 
""I did buy a bus bar toda

""I did buy a bus bar today, a Blue Seas at West Marine it has four studs."

YES; I did the same 12 years ago, totally good. This was the 600 amp job, as I recall. Each engine took a #2 to the bonding block, as did each starting battery. Also, ran a cable to the house battery(s) as well. Finally, the ships bonding conductor started there and ran aft."
 
"Will I need to run the bondin

"Will I need to run the bonding wire to this bus bar? If so, should I run a wire to each engine, or should I connect to the drive shafts? I thought since the bonding wire ran to each engine, then I ran the #1 or wires 2 from the blocks to the bus bar, this would be be all that is needed for the bonding system."
 
Good info guys. My 91 Tiara h

Good info guys. My 91 Tiara has same issue. Didnt know its an issue. Think with this bar you dont need the bonding attached to block... just attach to bar... i know my engine ground studs are packed...
 
"It's a "single point

"It's a "single point ground" or called "star topography". In any case, the bonding conductor (green wire or bare strap(s) run aft from the bus bar, and pick up the logs, shaft brushes, strainer, thru hulls, rudder, fuel tank, tower, windshield frame, and maybe swim platform brackets. I used 10AWG for the smaller items and #6 AWG for the big stuff. The big stuff being liable to carry lightning current. The furthest aft is the big, submerged zinc plate."
 
"Sinec the type of wire is bro

"Sinec the type of wire is brought up, I have a very heavy 1 " Wide tinned and braded "strap" type of flat wire.

It almost looks like one of those Chinese hand cuff things we played with as kids that you slip onto opposite fingers made of flat straw and when you pull them apart they get tighter?

Would this make a good bonding cable? It is not insulated, just flat stranded braid...I would say it is the equivalent of a #1 conventional boat cable, strand wise"
 
""tinned and braded "s

""tinned and braded "strap" type of flat wire. "

Braided is a bad idea. For bilge duty, you want either solid strap, well supported, or I've used #6 THHN house wire. The problem with insulated house wire is that you have to bare the insulation everywhere you tie in. In retrospect, a solid AWG6 bare copper would be ok, as long as you well support it. It cannot be allowed to have vibration swing. The best, in my opinion is that Guest tinned, flat conductor; it even has perforations to allow direct bolting of ring terminals. I used brass loose hardware, and then soldered the ring term to the strapping."
 
Ditto on the braid being bad..

Ditto on the braid being bad...great behind a V-twin but not on a wet boat. Three years is about it in a damp environment.
 
"I had gotten a 100' roll

"I had gotten a 100' roll mil-spec flat braid from a friend who is a radio engineer for a commercial station and they used it for ground connections to help reduce capacitive inductance. It is as wide as a belt to hold up your pants but, if it will not work...I could make up 100 12" ground straps for the bike"
 
"I guess when you're doing

"I guess when you're doing everything, there's always a post that's pertinent


I cleaned up my engine bonding wires just about 3 hours ago. On my boat, they're connected to the top of the sea strainer which is ultimately onnected to the transom zinc. It's about a 3' green wire coiled wire (like an old telephone cord).

In front of my battery compartment is a similar green wire which has been cut. I haven't removed the box to look any further but I can see a bus bar where this cut connector and a bunch of other black wires attach.

Would I be better off connecting the engine bonds here instead?

In my case, everything is daisy chained together. My engine bond goes....Sea strainer ----> seacock---->transducer----->Cutlass mounting plate---->Transom zinc.

What do you guys think?"
 
"bob:

if the blocks tie


"bob:

if the blocks tie into the bonding system at the strainers AND your engines start, evrything is connected. That cut wire may have been cut after another "substitute" was added. Some boat riggers have been know to be 'lazy' and won't hesitate to take a short cut, especially on friday afternoon. My preference is like Diver Dave described; with the tinned, perforated strap running fore & aft, and the individual parts having their connecting leads run with as short a wire as possible.

Now, I have to ask Al about that "capacitive inductance" ??????"
 
""Now, I have to ask Al ab

""Now, I have to ask Al about that "capacitive inductance" ??????"

yeah, I'd believe it reduces "skin effect", and "parasitic inductance". Both for RF, and lightning, which contains lots of RF current as well."
 
"Reactance-wise, I was taught

"Reactance-wise, I was taught Capacitive reactance is 'opposite' of Inductive reactance (some use + for Xl and - for Xc); I've never seen capacitive modify inductance. Not picking but trying to minimize my ignorance.

I'll by reducing the skin effect, especially for RF applications.

I wouldn't think parasitic anything would make any meaningful difference when it comes to lightning strikes. Some of the tests I reviewed had 10's of 1000's of amps flowing. I'd think one desires to minize the impedance for lightning protection. Bond would be good for that if you can keep it clean and dry."
 
""Capacitive reactance is

""Capacitive reactance is 'opposite' of Inductive reactance (some use + for Xl and - for Xc); I've never seen capacitive modify inductance. "

Yes, in fact, a resonance condition is met when a series Ind. reactance is equal and opposite to a cap. reactance. They are equal in magnitude and opposite in sign. The resultant is low resistance value with no "imaginary" or reactive part at all. In a parallel scheme, the same components will result in a very high resistor equivalent. This condition is totally dependant on the drive frequency, so primary resonance will exist at only one freq.

The word "parasitic" is used for components that have a typically non-desireable trait. In this case, big braid is trying, let's say, to ground the tower and make the transmitter safe from a direct lightning hit. In this case, the parasitic component of the braid is a series inductor of some value. It is not good to have inductance in series with a grounding/bonding element. So, the braid uses many small conductors, trying to minimize that effect. They don't need mechanical flexibility here, they need a very low Xl + R. Lots of parallel conductors minimize both Xl and skin effect, another issue. Litz wire is one step beyond even braid. For a given amount of copper, Litz is likely unsurpassed in minimizing RF parasitics in cable."
 
"I did'nt realize I had wr

"I did'nt realize I had writen inductance...it IS reactance
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OK, OK I found this on the web
....What Ba!! busters....I might as well go hang out with my "other" friends...their just as bad !"
 
"DD - i was refering to the wo

"DD - i was refering to the word "capacitive" used as an adjective for "inductance".

Al: I'll repeat it for you again - I'M NOT PICKING, just trying to get smarter..or less ignorant. One thing my increased age has shown - the more I learn, the easier I realize how ignorant i am."
 
"Yeah, "capacitive inducta

"Yeah, "capacitive inductance" is nonsensical to me, at least.

To boil all this off; Braid is better electrically, and we would use braid in a boat, except, like MM noted, it would turn into a green line of fuz in a few years."
 
"Couple questions as I seem to

"Couple questions as I seem to have a problem on starbord side as seeing some pitting on prop and rudder:

1) How do you attach to items like shaft logs that have no bolts?

2) Where do get shaft brushes?

3) I have some type of plate, about 4"x10", that is attached to outside bottom of boat but is not zinc is painted and maybe made of copper/bronze and has green onding wires attached? What is this?

4) I also have 31 Tiara w/ everthing bonded to motors, assuming it was built this way and Tiara knows what they are doing so why change it to a bus bar?

5) I dont have a stern zinc plate, is this worth istalling?"
 
"I can answer some questions,

"I can answer some questions, but my knowledge is limited and I am sure others will provide the missing details.

The bonding system in my Tiara is good, although after 20 years, it shows signs of corrosion in the wiring. Over time I will replace the terminal connections and wires if needed.

As for the bus bar, the battery charger was not wired correctly. It cooked two batteries and was already cooking a third. I bought the boat a few months ago and have been going through all the systems as fast as I can. In reading the installation instructions for the Protech 1220i battery charger, it suggested all the batteries be connected to a bus bar. I have plans on changing the charger out for a Minn Kota 4 bank and those instructions also shows the negative connections to a bus bar. It made sense to me to go ahead and add one. So now I have 4 negative bus bars, 2 are behind the AC/DC panel, one is under the dash and now the battery bus bar.

While it is true Tiara makes a good boat and uses good equipment (my 2nd Tiara) there are economic considerations they make so they can hold as much profit as possible. Meaning some equipment can be improved. The Norcold is one example.

My thru-hull for the generator has no screws that one can attach a bonding wire. It is really a cheap installation job, it is factory installed Onan. They bonded it using a hose clamp, the wire is bare underneath the hose clamp. When I haul the boat, this is one thru-hull I plan on improving, not sure how yet.

I do have a Zinc plate in the stern. But my boat is a little different than the 31.

Hopefully this answers some of the questions."
 
"RM -

1) are you sure


"RM -

1) are you sure there are no mechanical fasteners on the shaft log? Mine were completely corroded and took some cleaning up before I could find the remnants of the bolt heads.

You wouldn't have easily seen them if you just looked down into the engine room, not sure how far into this you are.

I've since replaced them with Silicon bronze. BTW, McMaster Carr is a great source for hardware like this.

3) It sounds like you're describing the backside of the strut/cutlass bearing mount. My Trojan is similar and serves as sort of a junction point for the green bonding wires before connecting to the transom zinc.

Bob"
 
No bus bar on the 1991 3100 Op

No bus bar on the 1991 3100 Open Tiara. My 8 awg green crosses the engine sides on sea strainer. I think the star topology with bus is the way to go. Maybe next year for me. I have gone thru all the connected ends visually and will continue now with continuity.

I don't have a zinc plate so that I will add this weekend as I have weekend on sling at the yard. I will use 1/2" silicon bronze to set the path for better grounding to come.

Keven are you sure tiara did that gen setup? Tanks were recalled them years and sub contracters may have did your gen...
 
"[b]quote: "it suggests co

"quote: "it suggests connecting all the negative cables from the batteries to a common ground"
Just my two cents here:
One reason that I can think of for this not being advisable would be redundancy!
There is no redundancy if all Battery Bank Neg cables attach to a common "remote" or "OFF engine" location/termination point (if I understood you correctly).
With each battery bank having their own engine termination point, you now have redundancy, should one fail.

A Negative Buss is great for subsequent D/C circuits."
 
"Scott,

I am sure Tiara did


"Scott,

I am sure Tiara did the generator install because I have a copy of the test run report, which indicates installed equipment (generator) among other stats like WOT, range estimate, etc.

However, being the third owner, one can never be 100% sure about anything.

Prior to buying the boat, I did confirm the gas tank was replaced by contacting Tiara. They stated the tank was replaced because they have rescords to the fact. The problem is the cockpit sole would have to be cut to get it out and I see not indication this happened."
 
"RM:

That block of metal ma


"RM:

That block of metal may be a Dynaplate or a clone. They are typically added to ensure a good "ground" is made with the water, either for radio (RF, especially SSBs) or lightning protection reasons. They should NOT be painted."
 
"Thanks all. Mark that's w

"Thanks all. Mark that's what I thought it was, it was painted when I bought the bought and need to trace and see where the ground wires lead to."
 
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