Alternator to batteries

[sailinbob1]

Originally Posted by sailinbob1

I recently, like Thursday, added a new instrument cluster today my 2qm20 Yanmar, and thanks again for everyone's input, works great,though I fried an amp meter. While I was doing that,I ran wires to the volt guage, and noticed there was no wire running from the alternator to,well, anywhere. A friend replaced the alternator when I bought the boat,so I had no idea. No excuse,but true. I have a,what I believe is,100 watt flexible solar panel, running to a Sun Saver 6 charge controller, and 2 new AGM 1000 cranking amps/100 amp hour batteries. The panel is 11 ft long, and 14 inches wide,and my batteries stay at close to 14 volts,seldom dipping below 12.6 volts,when there's little,or no sun. I'm refitting the boat,and don't the electrical is a mess. Don't ask about the battery box! She had a 13 switch electrical distribution panel, but, a previous owner , has piggy backed everything on to a 6 switch panel. I'm ordering a 13 switch AC/ DC panel from Paneltronics. Thankfully, everything works. Ok,that's the background. Here are my questions. 1, I've run a hot wire, from the alternator, to a single bus ,which was feeding the 6 switch distrbution panel ,from the isolation switch ,to the batteries. Is this a proper configuration? Or should I run it to the isolation switch? I ,when running the engine, keep the isolation switch in the both battery position. 2, my solar panel has the controller box, I mentioned , to keep me from overcharging the batteries. I'm not mechanic, but I'm reasonably intelligent,and know, in my car,my alternator doesn't overcharge my batteries, so,do I need to be concerned that my boat's alternator is pumping juice into the batteries when I'm underway, or does it operate the same as my car? I guess what I'm asking is,do I need to add something between the alternator, and the batteries, that performs the same function as the controller box,or is that inherent in an alternator? Thanks,hope I made some sort of sense. Will appreciate any input. Thanks.

Trying to get this in the proper forum. Help please

[Ding Duck]

Hi SailinBob1, Check to see if there is a cable from the Altenator to the +ve terminal on the starter motor. Saves running a second cable all the way back to the Battery. This cable may only be 6 or 10mm2 (don't know what that is in AWG). Never turn the Batteries off when Altenator is running, will do serious harm to the regulator. The exception is if you have Aux Contact to disconnect the field, but still not a good idea.
You don't need anything special between the Batteries and Altenator. The Solar Regulator will look at Batt Volts and decide how much it should charge. Same for the Altenator, it's looking at Batt Volts.
Good Luck with the Refit

ps Was the Ammeter fry-up just a bit of a whoopsie?

[sailinbob1]

Definitely, a whoopsie! I disconnected the wire I had run from the alternator to their bus ,and yes there is a wire from the alternator to the starter,and the wires to the amp meter. The volt meter works fine(was going to be redundant anyway,once I install the new distribution panel which has one.). I'll replace it with a tachometer, or the amp meter will make an attractive plug. I'm not a mechanic. Seemed odd to me that there was nothing connecting the alternator to the batteries. It's my understanding that the alternator charges the batteries via the starter. Is that correct? Stu sent me a link to,basically, electrical for dummies. Lol... Explained it well. As I stated. Everything on the boat works. My instrument cluster was falling apart, so I had no choice but to replace it. Once I get into the yard,I'll move it up to the helm. At present, I have to stand on my head to read the guages. I always keep the isolation switch in the both position when the engine is running. The only difference I've noticed, since finishing this project is,my bottom finder is giving me incorrect readings for both depth,and water temperature. Since I'm a sissy,and can't tolerate the cold,I haven't scraped the bottom in 2 months. I checked the wiring, and nothing seems amiss. The transducer is internal,so I figure I'm reading the life growing on the bottom. The depth finder says I'm in .07 feet of water. Since I draw 5.5 ft,I believe I would have noticed. The temp reads 79º. Since everything else works,I figure I'm just getting a false reading because of the growth. Any more input would be greatly appreciated. Have a great day!

[sailinbob1]

Sorry spell check made a couple adjustments. I've disconnected the amp meter.

[Stu Jackson]

The links I sent you in your previous post come from here:

Electrical Systems 101

There is a post in there about how ammeters work.

[sailinbob1]

Ok,didn't realize it was you. It was very helpful. I'll see about getting the book. My electrical is horrendous.

[Ding Duck]

Originally Posted by sailinbob1

It's my understanding that the alternator charges the batteries via the starter. Is that correct? Stu sent me a link to,basically, electrical for dummies. Lol...

Bob, this is correct, the altenator is connected to the battery via the starter cable

The transducer is internal,so I figure I'm reading the life growing on the bottom. The depth finder says I'm in .07 feet of water. Since I draw 5.5 ft,I believe I would have noticed. The temp reads 79º. Since everything else works,I figure I'm just getting a false reading because of the growth. Any more input would be greatly appreciated. Have a great day!

Since the transducer is internal, check to see if there is any air pockets between the transducer face and the hull. There needs to be no voids for it work correctly. You could try a little petroleum jelly on the face to check for voids. As you know, it works on Ultrasonics and measures the time of flight. Reading of 0.7 is probably the min value it can read so it may be hearing the echo caused by the void. It will be indicating 79 F because it is reading the air temp and not water temp. There is a little temp sensor built into the face of the t'ducer
Hope this helps

[smac999]

Originally Posted by sailinbob1

Definitely, a whoopsie! I disconnected the wire I had run from the alternator to their bus ,and yes there is a wire from the alternator to the starter,and the wires to the amp meter.

so you had 3 wires feeding from the alt?... if you are trying to put an amp meter on the alt (I wouldn't bother) then you need a single line from alt, to shunt, and then to your desired charging loction. which could be many things based on the rest of the system and how you charge multiple banks. the easiest and shortest is the start post as then it used the large start cable back to the batteries.

if you went to a post that feeds 6 swtiches. I would be highly concerned the wire between that post and the batteries was too small. as it was only ment for a few loads. not an alternator.

[Ding Duck]

Stu, you may also find this interesting. Bit dated now, but the principals are valid. Not sure if the use of shielded cables is relevant to non commercial vessels. Certainly worth noting for some applications.
Also, a nice simple schematic for boat wiring
Hope this helps
http://ir.library.oregonstate.edu/xm...%20622_ocr.pdf

[sailinbob1]

Ok,here's my plan. I'm going to take extensive photos tomorrow, of everything that exists at present. I take full responsibility for some of it,but I wouldn't have done, what I have,with out being 100%positive about what I was doing. The rest I attribute to the previous owners. I'll post that tomorrow. I've ordered a Paneltronics 19 switch AC/ DC electrical distribution panel today. I don't need that many switches at present, but plan to add entertainment, and other components, in the near future. I honestly appreciate all of your suggestions, and I mean everyone, so let's look at what exists, and walk me through where I'm trying to go. I'm a carpenter/ tooler. I've been on the water all my life,and have refurbished 3 sailboats, but none with the electrical issues, that this boat has. It's a cluster f***. I don't want to bring in an electrician. This is my boat
Not some flipper. Unless someone makes me an offer I can't refuse. Lol... I need to know this by rote,as I plan to sail as much of the Caribbean as I can,with the time I have left. Not that I'm in a rush to go. All of everyone's input is appreciated, but I feel like I've not fully explained my dilemma. I'll post extensive photos tomorrow. Keep in mind. My engine is a 70s/80s model 2qm20 Yanmar and at present, I've got bare bones electrical. Hummingbird 365i depth finder, cabin lights,running lights,anchor light, stern light,and that's about it. I'm bringing her into the 21st century. She's a solid Bluewater boat worth having. I'll appreciate all of yall's input. Fair winds! As an example, here's a small portion of my woodwork. It's sapele.

[Stu Jackson]

Originally Posted by Ding Duck

Stu, you may also find this interesting. Bit dated now, but the principals are valid. Not sure if the use of shielded cables is relevant to non commercial vessels. Certainly worth noting for some applications.
Also, a nice simple schematic for boat wiring
Hope this helps
http://ir.library.oregonstate.edu/xm...%20622_ocr.pdf

Thanks, duck.

I found it very interesting. Kinda like reading the Dead Sea Scrolls as a daily newspaper.

1981 was five years before they built my boat, and even in those five years a lot of the information in that pamphlet was overtaken with technology.

Like diodes (not the ones in the alternator), for example, that are included in the emergency battery discussion. Not a good idea. The battery combiner was invented before that pamphlet was published, and folks were using relays instead of diodes in charging systems before then, too.

And like the ammeter in the alternator output. It has a shunt, but most installed in cockpit panels simply don't, therefore having all alternator output run to the cockpit in both distance and usually small wire makes little sense these days, with Smart Gauge and battery monitors. New skippers wouldn't know that.

All basic boat electrical books cover this stuff, and better.

Much has been learned and documented and posted on electrical systems since 1981.

This was a nice museum piece, like the old Micrologic 8000 loran C my PO left on my boat, since removed.

The material could well be misleading, compared to newer material, online and in books. Especially for newbies.

Thanks for sharing though.

[Stu Jackson]

Originally Posted by sailinbob1

Ok,here's my plan. I'm going to take extensive photos tomorrow, of everything that exists at present. ..................
....................I'll post extensive photos tomorrow.

Nice woodwork. Wish I could do that.

Let us warn you now:

PHOTOS of wiring, terminal strips, batteries, etc. are useless WITHOUT WIRING DIAGRAMS.

We have learned this the hard way when trying to help folks with questions.

[Ding Duck]

Hi Stu, I did say it was dated. Certainly a lot has changed, but a lot stays the same. For SailinBob1 the simple circuit diagram (Fig 3) with wire sizes may be a good place for him to start as he's doing a basic rewire of his boat.
The use of Shunt's to indicate Current hasn't changed since 1981, whether it be Analogue or Digital. Perhaps the mV/A has changed dependant on the manufacturer.
Back on '81 Solar Regs weren't a consideration to the author either.
Anyway, it is what it is.
Cheers

[Stu Jackson]

Originally Posted by Ding Duck

....................with wire sizes may be a good place for him to start as he's doing a basic rewire of his boat.
Cheers

Yup, you did say dated. All I added was why "dated" may not be the most information information out there.

For yet another example: wire sizes? Lousy place to start. 4/0 or 2/0 wire? You certainly know, but newbies may not, that wire sizing is based on load and distance. 4/0 wire for a 60A alternator would be applicable for 100 foot ship, not a recreational boat.

I have a 100A alternator on my boat and use #2 (NOT 2/0) wire for the AO.

Let's not distract from the teaching mode by providing some questionable information.

I know your heart's in the right place, but simply saying it's dated and not telling Norman Newbie what's wrong with it may not be helpful in the long run.

[sailinbob1]

Thanks, you'd appreciate the rest of the woodwork ,I'm sure. I'm a very talented carpenter, though more structural, than finish,or cabinetry. I'm reasonably intelligent, and though I realize, a picture, isn't ,necessarily, worth a thousand words,I'll post what exists, with a hand drawn schematic. I took architectural drafting ,and design at Tech school, so,perhaps, I can produce a drawing that better explains my present situation. Thanks for your input. Fair winds.