Rewiring from Scratch
- Thread starter Wireman
- Start date
Guys please, please, please take note of how the OP presented his questions.
Hew drew a diagram of what he had or wanted to use!
He posted it so we could EASILY fill in the blanks!
This is how you ask a question on wiring!!!!!!!'
Every Windows computer has MS Paint and it is easy to use. I am sure Mac's have similar....
The more info you share the easier it is for us to help. That drawing took me all of about 6 minutes because the OP did most of it..
Hew drew a diagram of what he had or wanted to use!
He posted it so we could EASILY fill in the blanks!
This is how you ask a question on wiring!!!!!!!'
Every Windows computer has MS Paint and it is easy to use. I am sure Mac's have similar....
The more info you share the easier it is for us to help. That drawing took me all of about 6 minutes because the OP did most of it..
Thanks Guys-
This is what I'm dealing with as I'm sure many older boat owners are. Will put together a diagram for any further Q&A.
Dan
This is what I'm dealing with as I'm sure many older boat owners are. Will put together a diagram for any further Q&A.
Dan
Attachments
Guys
Hopefully this is not a highjack, but still deals with the sw in the alt line in MS's diagram and my earlier question.
After looking at Stu's fig 3 and MS's diagram, and knowing the alt does not share the start cable in my boat, I realize now that my mystery starter switch is actually there to isolate a bad start battery I believe. The conceptual control diagram shows the start battery is essentially wired to the starter via the #2 post on the 1-2-B-Off switch. The HO alt is connected to the house battery.
In normal ops the 1 position is selected, the mystery start bat switch is closed and the ACR charges the start battery. The only advantage this may offer is there is no voltage droop or starter transient/noise put on the house bus and it's electronics when starting the engine. I can't imagine either is a real issue with sufficient bank size if starting using house bats only.
If the start bat dies, I must isolate the start battery first then set to the BOTH position to connect the house to the starter. Note that fuses and grounds aren't shown for clarity.
My hats off to this thread and its contributes for forcing me to trace the wiring down and documenting it. PO did not know how it worked and recommended to leave it as is. Comments?
Dan
Hopefully this is not a highjack, but still deals with the sw in the alt line in MS's diagram and my earlier question.
After looking at Stu's fig 3 and MS's diagram, and knowing the alt does not share the start cable in my boat, I realize now that my mystery starter switch is actually there to isolate a bad start battery I believe. The conceptual control diagram shows the start battery is essentially wired to the starter via the #2 post on the 1-2-B-Off switch. The HO alt is connected to the house battery.
In normal ops the 1 position is selected, the mystery start bat switch is closed and the ACR charges the start battery. The only advantage this may offer is there is no voltage droop or starter transient/noise put on the house bus and it's electronics when starting the engine. I can't imagine either is a real issue with sufficient bank size if starting using house bats only.
If the start bat dies, I must isolate the start battery first then set to the BOTH position to connect the house to the starter. Note that fuses and grounds aren't shown for clarity.
My hats off to this thread and its contributes for forcing me to trace the wiring down and documenting it. PO did not know how it worked and recommended to leave it as is. Comments?
Dan
Attachments
Morning All,
Thanks for all the wonderfully informative answers and thoughts. I am just trying to get mu head around the earth / ground / bonding system. Please have a look at the pic below and suggest any alterations or corrections on the added Bonding system.
Thanks once again for all the input.
Cheers,
Mike
Thanks for all the wonderfully informative answers and thoughts. I am just trying to get mu head around the earth / ground / bonding system. Please have a look at the pic below and suggest any alterations or corrections on the added Bonding system.
Thanks once again for all the input.
Cheers,
Mike
Bonding the keel and the through hulls to the motor means they are all electrically connected. If the motor block/transmission/shaft are bolted together without a shaft saver the shaft zincs will be protecting all the underwater metals - not just the shaft/propeller assembly. So you will probably need more zinc to get through the year.
Likewise if you have a sail drive provided the drive is electrically connected to motor block. At least one manufacturer insulates the motor block from the sail drive unit so the drive zinc protects the drive unit only.
If the motor is insulated from the shaft or drive unit then you need a separate zinc in the bonding circuit to protect the underwater metals. If you have a strut include the shaft strut in the bonding circuit.
Even if the motor is insulated from seawater make sure the bonding circuit is fastened to the motor block and so necessarily to DC negative - just as your diagram shows. That way your now bonded metals are electrically attached to DC negative. The connection between DC negative and the bonded metals provides protection from stray DC current as well as from galvanic activity.
Please note there are plenty of folks who skip bonding altogether and there are good reasons to suppose bonding the underwater metals is not necessary.
Charles
Likewise if you have a sail drive provided the drive is electrically connected to motor block. At least one manufacturer insulates the motor block from the sail drive unit so the drive zinc protects the drive unit only.
If the motor is insulated from the shaft or drive unit then you need a separate zinc in the bonding circuit to protect the underwater metals. If you have a strut include the shaft strut in the bonding circuit.
Even if the motor is insulated from seawater make sure the bonding circuit is fastened to the motor block and so necessarily to DC negative - just as your diagram shows. That way your now bonded metals are electrically attached to DC negative. The connection between DC negative and the bonded metals provides protection from stray DC current as well as from galvanic activity.
Please note there are plenty of folks who skip bonding altogether and there are good reasons to suppose bonding the underwater metals is not necessary.
Charles
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http://www.westmarine.com/WestAdvisor/Marine-Grounding-Systems
What material are your thru hull valves?
Sounds like a good time to ask a "bonding" question.
On our boat, DC negative is connected to the engine block and there is a zinc on the prop shaft. There is also another rectangular zinc bolted to the hull bottom - but it's not connected to anything. Should it be? Why is it there?
Also, after reading the West Marine link about bonding the mast to a keel bolt (external ballast) or a ground plate - why would you also bond the shrouds and forestay? The article states that the purpose of bonding is to give the mast the same electrical potential as the water surface. If the mast is bonded then that is accomplished - or isn't it?
Want to wire things up properly this spring...
Thanks,
Chris
On our boat, DC negative is connected to the engine block and there is a zinc on the prop shaft. There is also another rectangular zinc bolted to the hull bottom - but it's not connected to anything. Should it be? Why is it there?
Also, after reading the West Marine link about bonding the mast to a keel bolt (external ballast) or a ground plate - why would you also bond the shrouds and forestay? The article states that the purpose of bonding is to give the mast the same electrical potential as the water surface. If the mast is bonded then that is accomplished - or isn't it?
Want to wire things up properly this spring...
Thanks,
Chris
The original question was how to make up reliable boat-wide DC wiring. The follow up question involved connecting (bonding) underwater metals.
Your question concerns bonding metals above the water line. Above waterline bonding is really a matter of lightning protection. I have never met (or read of) anyone who could assure that any above waterline bonding system will protect from lightning strikes - whether direct or nearby - no matter the design.
In short - can't help but this matter has been discussed in the archives.
As to your separate (apparently unused) zinc - it is very likely this zinc was at one time wired (bonded) to the through hulls, strut, and possibly your keel. Otherwise it may be a sintered bronze radio ground plate - not a zinc at all.
Charles
Your question concerns bonding metals above the water line. Above waterline bonding is really a matter of lightning protection. I have never met (or read of) anyone who could assure that any above waterline bonding system will protect from lightning strikes - whether direct or nearby - no matter the design.
In short - can't help but this matter has been discussed in the archives.
As to your separate (apparently unused) zinc - it is very likely this zinc was at one time wired (bonded) to the through hulls, strut, and possibly your keel. Otherwise it may be a sintered bronze radio ground plate - not a zinc at all.
Charles
Hey All,
Just a quick update on the rewiring. Today the motor started and proceeded to charge the batteries! Next will be the connection to the DC panel. I am sure I will need a helping hand with this as well.
Thanks again for all the help,
Mike
Just a quick update on the rewiring. Today the motor started and proceeded to charge the batteries! Next will be the connection to the DC panel. I am sure I will need a helping hand with this as well.
Thanks again for all the help,
Mike
Attachments
Hi All, The rewiring is progressing nicely. I have a question for all in the know. The Blue Sea SI's led keeps flashing and I think it has something to do with my connection to the starter engagement terminal. The setup I have is a on of key switch with a push button start. I currently have the start isolation from the ACR connected to the positive wire on the push button ( black wire in the pic ). I read up and the slow flashing means " start isolation wire energised ". Any help will be greatly appreciated.
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You are on the "energized" side of the push button. You need to be on the side that only makes when the button is pushed.,..
Dan, that looks just like the two switch diagram in this link provieded earlier: http://c34.org/bbs/index.php/topic,6604.0.html
Looks like "Ya Got It!" :dance:
Looks like "Ya Got It!" :dance:
Well, his name is "Wireman"Dan, that looks just like the two switch diagram in this link provieded earlier: http://c34.org/bbs/index.php/topic,6604.0.html
Looks like "Ya Got It!" :dance:
If I have a component that has three wires red (positive), black (negative) and a green (earth). I know the red and black go onto the dc panel, but not sure where to wire the green earth wire. As per the drawing, does it go onto the negative bus, which in turn is wired to the engine block or should it be wired directly to the block? Any input would be greatly appreciated. Thanks again,
What is the component? This sounds like 240v ac colour coding rather than 12v. 12v would normally have 2 conductor red/black but no green. (Newer 12v DC coding is red/yellow to avoid this confusion with AC wiring).