alternator regulators -- MOA

Wed, February 05 2025, 04:56 [ Login ] [ Contact Forum Admin ] [ Main index ] [ Post a new message ] [ Search | Check update time | Archives: 1, 2, 3, 4, [5], 6, 7, 8, 9 ]

[ Next Thread | Previous Thread | Next Message | Previous Message ]

Date Posted: - Monday - 12/14/09 - 1:45am
Author: Randall, Murre, M31
Subject: alternator regulators

Am moving the batteries into the main cabin and replacing much of the wiring. Ever so slowly.

I think every other job on Murre has been easier than this one.

Pursuing Murre's old, grimy, tangle of wiring has a quality about it akin to a high school dissection lab, except, as I recall now, the nervous system of the frog I flayed years ago was much better organized.

So many wires lead to nowhere on Murre, I'm not sure which wires actually connect.

Today it was impossible to tell what was what, so I started getting rid of one wire at a time, then testing that the lights in the cabin still worked, then getting rid of another.

Soon there weren�t any wires coming off the battery but the boat cable. I�ve always known Murre is magical, but running the cabin lights, the water pump, and the VHF radio off nothing more than the undulating warp and woof of the universe is quite a trick.

In any case, and more to the point, during my excavations, I found a small, brown, rusted box tacked under the deck above the alternator. Some scull scratching and research in Casey suggest this is the regulator. I think it was built in the 1920s and so I will replace it with a model that at least still carries paint.

But I am at a loss to know which one.

Any suggestions on regulators?

RR

[ Next Thread | Previous Thread | Next Message | Previous Message ]

Replies:

[> Alternator regulator -- Steve M-32 SEAN O'Sea, - Monday - 12/14/09 - 11:22am

THe first thing you'll need to do is to figure out which (or at least what kind) of alternator you have. Presumably because you have an external regulator the alternator requires one but because of the age and history of the boats and the state of Murre's wiring that is not a given. Look for some numbers on the alternator and a manufacturer if you can find one. Because we have diesels we don't have to have marine alternators so there is a good chance that an automotive one was used. Pulling it and taking it down to your local old school auto store might also yield some good info. There is a lot of different models, types and ways of wiring these things s othere will be many variables as you try to figure this out. I recently went through the same thing on my engine (though I haven't wired the boat yet) so I can give some help but I need more info in order to give more details.

[ Edit | View ]

[> [> Voltage Regulators -- Paul - 1971 M31 - #106, - Monday - 12/14/09 - 7:43pm

What Steve is eluding to is that most newer (automotive) alternators have a built-in regulator for Voltage Management.

Newer alternators contain no permanent magnets (as opposed to the old fashioned dynamos) and need a 'steering current" from a minimally charged battery, to engergize the core (to make it a magnet), so that it will induce a current in the stator once it rotates the field within the charging coils. A lot of people toss perfectly good alternators because they didn't produce a voltage/current when "tested". They won't, unless you charge the rotor coils.

If you have a reasonably updated alternator, chance are it contains it's own regulator, likely with qualities that surpass the old mystery box you discovered.

As regards the only line left from the battery powering the entire boat - except perhaps for some items many people like to see "hardwired" to the battery - such as the primary bilge pump and alarm and VHF radio - typically the battery bank will supply power through a heavier cable to a main breaker mounted on the panel and from there through "normal" lines to the various individual breakers subblying and protecting their designated circuits.

With only this main line left, you probably have all the switches still "hot" but no bilge pump and your VHF radio won't work...

I don't (yet) know this boat - maybe I am right... ;-)

[ Edit | View ]

[> [> [> More hardwired stuff... -- Paul - 1971 M31 - #106, - Monday - 12/14/09 - 7:56pm

The engine panel is likely hardwired to the battery as well.

As are the glow plugs (or the "cold start assist" as is used on the Marinized (no pun) Perkins engines)

The main power to the starter motor

12V auxilliary power outlets

The fan the PO mounted in the V-Berth

Etc.....

Note that "hardwired" means it has a designated line directly to the battery (often also a return "neutral) and it is protected by an in-line fuse rated specifically for the equipment.

[ Edit | View ]

[> alternator and hardwire -- Randall, - Tuesday - 12/15/09 - 1:44am

Thanks gents.

Steve, I'll have a closer look at the alternator next weekend. The regulator discovery came at the end of the day when my brain wasn't up for more riddles.

By the way, thanks again for the reference to Ronko plastics. Mind boggling selection. Still can't seem to find quite the right shape, but so it goes...! :)

Paul, I think it's safe to say I don't have an up to date alternator. I don't think anything on Murre is up to date, unless that date is 1972. :) But I'll check it out. Given the price of regulators, would it be as cost effective to replace the alternator w/a smarter one?

Both batteries had tons of odd wires coming into them with no busbars, posts, or fuses for that matter, to "interrupt" the flow of electricity to the device in question. This was why I was so confused when, after removing all but the battery cable, the house still lit up like a Christmas tree.

As it turns out, all these wires were either AC charger or AC plug related or dead end wires to nowhere. A lot more digging revealed that a hot boat cable runs under the engine to a large, naked fuse whose connector looks like a lasagna noodle, and thence to the starter. ALL the house electrics run off the top post of this fuse. Makes sense ONLY in that the "factory" fuse box is a straight shot up from here.

The fun just doesn't stop! :)

RR

[ Edit | View ]

[> [> Alternator -- Paul - 1971 M31 - #106, - Tuesday - 12/15/09 - 9:02am

Here's a good link to an article on alternators: http://www.autoshop101.com/trainmodules/alternator/alt112.html

You can pick up a working alternator with built-in regulator at any wrecking place. Pulling them apart, cleaning and replacing worn components is a breeze.

Here's an article on rewiring - http://www.tongacharter.com/report-wire.htm

Careful with 12V - I almost burned my boat down because I let down my guard. 12V will not "blow" wiring or equipment, rather it will make it glow like a light bulb... Once I accidentally shorted a small line to hot and it instantly lit up, with burning insulation dripping off it, as far as I could follow it... I was waiting for it to fail (too hot to touch) but it never did - just kept on glowing bright orange and the boat was filling with toxic black smoke from the burning, dripping insulation. after what seemed an eternity (maye 2 seconds) I wrapped a screwdriver around the glowing wire and tore it loose. Not knowing what was set aglow in areas that I could not see, I stayed on the boat (in the fumes) for at least a half hour to make sure nothing would "puff" into flames behind my back.

12V is very dangerous because it gives most folks a sense of harmlessness because it doesn't bite. But believe me, it will set anything and everything on fire if you let it.

If you have a starting battery sitting around somewhere, just practice with a small piece of wire - accross the two terminals - it will light up and glow forever.

FWIW

[ Edit | View ]

[> [> Alternator regulators -- Steve M32 SEAN O'Sea, - Tuesday - 12/15/09 - 10:51am

I went with an older style Delco with an external regulator so that I could hook up one of the newer multi-stage marine regulators to it. My understanding is that can't be done with one of the newer internally regulated alternators. If you want a mind-numbing treatise on the subject muddle your way through Calders' "Boatowners Mechanical and Electrical Manual" If you only have one battery bank and do not stay on the hook for more than two days or so you may not need a fancy setup and could go with an internally regulated model. I wanted two banks (starting and house) and the ability to keep the batteries topped off (see Calder). This is a subject with more opinions than there are boaters and it is changing all the time so take everything said with a big grain of salt and do your own research.

[ Edit | View ]

[> Boat electrics -- Dan M32 #36 Independence, - Friday - 12/18/09 - 9:13pm

Since I'm going to be comletely rewiring Independence soon I bought Don Casey's Sailboat Electrics Simplified. Great book. Also read Calder's.
Dan

[ Edit | View ]

[> More Questions -- Randal, Murre, M31, - Monday - 01/ 4/10 - 12:22am

Thanks for the great feedback, gents.

I always forget to go to Calder. Not sure why. Maybe the book's too damn big. But thank you for the hint. I read the "mind numbing" thesis you reference, which is really all of chapter one, and am now working through two and three. Essential. Should have read it first, but if I had, I might never have started.

Still have questions about the alternator and regulator, though, and these are questions I've not found answers to in Calder ... yet. Since this is a longish post, feel free to answer simply with "Calder" if I just need to keep reading.

ALTERNATOR: I think it's an oldish Delco, but I think this only because of the form factor--there's no branding on it, but it looks the same as those on the web, here: (http://www.motorcityreman.com/7127marine.html). It has two points: Batt and Ground and that strange black nodule that says "don't remove". It has SAE J1171 tapped onto the casing, which google tells me refers to "Marine Ignition Protected". Don't know what that means yet.

***Big Question Here: how can I tell its rated amp output? I need at least 100 and can go as high as 120. Can my digital voltmeter help sleuth this?

ALTERNATOR WIRING: The 10AWG hot wire from the alternator runs up over the engine and then splits into three directions: 1) red to the ignition switch at the aft of the boat; 2) red to the distribution panel (disconnected); 3) white to a shunt on the port side of the engine. This shunt has a 2AWG hot wire to the starter's hot point, which is wired to the starter battery. THIS WHITE WIRE IS THE ALTERNATOR'S CURRENT CHARGE PATH BACK TO THE START BATTERY.

***Is this arrangement even close to standard? Shouldn't the "split" be via a terminal block? Right now the wires are simply nutted together and taped. (Wow!)

***I want the alternator to charge the House bank, not the starter bank. Can I simply move the shunt and white wire to the house banks? (Can't see why not.) Is there anything sacred about having the Alternator hot wire pass into a battery via the Starter?

REGULATOR: It's an old, a small square box with no branding. It has three wires: red, black, and blue. Black goes into the meter in the cockpit, red goes to BATT on the alternator, and blue goes nowhere at all.

***If blue goes nowhere, can the alternator function? What's blue suppose to do?

I have the new batteries and new switches installed. One cranking battery for the starter; three deep cycle, 150 amp hour 12 volts for house (paralleled). Currently the alternator feeds into the start battery, not ideal, soon fixed. But I charged the lot this weekend anyway and via an Automatic Charging Relay. Pretty slick.

At moderate high to high revs, the alternator output was 14.2 to 14.4 volts, which I think is good. At the batteries however, the voltage jump was not the full volt ("or more") that Casey suggests is healthy, but it wasn't as low as his diagram either. The new house batteries were quite low on charge when I bought them: 12.15 volts. When I started the engine, they only jumped to 13.0. This voltage climbed steadily as the batteries charged. After two hours it was 13.31. After resting overnight, the charge was 12.4. Another two hours charge and resting overnight brought them to 12.55.

***Is the above suggestive of an alternator being asked to do too much (charge 4 batteries where it was use to charging only 2)? Is the regulator set too low? (I don't think it's adjustable.)

------

This is a drawing of the switch set up I just installed using Blue Sea hardware (http://bluesea.com/). I wanted to be able to separate the Start and House banks physically, yet combine them as needed. To do this, I installed a Blue Sea Dual Switch with an extra "Combine All" mode cross connected to a Single Blue Sea switch. The cross connect (red dotted line in the drawing) is what does the trick. Wired this way I can combine all batteries or, by leaving the start switch off but turning the dual switch to "combine", I can use the house batteries to start the engine but bypass the, presumably dead, start battery.

I also have all battery banks combined via an Automatic Charging Relay.

Dual Switch with Combine Function: http://bluesea.com/category/1/products/5511e
Single Switch: http://bluesea.com/category/1/products/9003e
Automatic Charging Relay: http://bluesea.com/category/2/productline/overview/387

Click to enlarge.

Quickpost this image to Myspace, Digg, Facebook, and others!

[ Edit | View ]

[> [> Electrical -- Steve M-32 SEAN O'Sea, - Monday - 01/ 4/10 - 11:25am

Oh boy, where to begin? I guess I'll start with the simple. "Marine Ignition protected" means that it is protected against sparking. The idea behind this is primarily with gas engines although it's not bad in regards to propane either. When you have an explosive, heavier than air gas on board (gasoline vapors, propane) it can build up in the bilge. That is why on gas powered boats you have to use a blower to vent the bilge before starting. It's also a good idea to do it on boats with propane installed. It's not required on diesel powered boats because the vapors aren't explosive. Diesel is rated as a combustible, not a flammable. I guess this a long answer to a short question but there you go.

As far as alternator size, there really isn't one that is too small but there is definitely one that is too big. A small alternator will charge your banks just as well as a big one, it will just take longer. When you get to the section of Calder regarding bulk charge vs top off charge etc I think that will become clearer.

I'm curious as to how you plan to maintain a charge in your starting battery?

A better investment for your money instead of a new alternator might be one of the multistage regulators on the market becuase the regulator was not designed to charge a house bank but a starting battery which has a different use/charge pattern than your house bank. Again, see Calder :-)

I'll stop here for now. Keep reading and ask away, I and the others here will try to not give you too much conflicting advice. One last thought. It is important to keep in mind what Calder is writing about. He is writing about an "off the grid" cruising boat with refrigeration, entertainment systems, pressure water etc. If your boat does not have all those goodies and you're not going out for more than a week at a time without pulling into a marina your system does not need to be anywhere near as robust as what Calder says is necessary. Calder himself tells you this in the book but it is easy to overlook that part.

[ Edit | View ]

[> [> [> How do I charge the start battery? -- Randall, - Tuesday - 01/ 5/10 - 4:01pm

Check out the drawing on the previous post. Between the two switches I've installed an automatic charging relay that bypasses the switches and connects the batteries of both banks when **either** senses charge voltage coming from the other of 13 volts or more for 2 minutes. When this voltage drops belwo 12.75, the connection between the banks is severed.

Slick. And definitely works on Murre.

The reason I'm connecting to house is they are likely drained more than the start battery more often, and since the regulator senses only the bank it's connected to and defines charge delivered by that, I want it to sense the bank that needs the most help.

One error of mine that Calder has been kind enough to point out: I should have bought a deep cycle battery for start. The relay/regulator technology can't regulate charge to differing battery needs. The type of charge the heavy walled house needs is not the same as that needed by the thin walled start, so I will likely be overcharging the current start battery because house needs a heavier charge over a longer period.

[ Edit | View ]

[> Alternator setups (Link) -- Paul - 1971 M31 - #106, - Monday - 01/ 4/10 - 10:13pm

As requested, I won't go into what I believe your setup is as it too would still be a guess and perhaps only add to what confusion may already exist.

This link may offer some insight though..

http://images.google.com/imgres?imgurl=http://www.ebasicpower.com/charge/images/alternatorwiring.jpg&imgrefurl=http://www.ebasicpower.com/charge/alternatorwiring.htm&usg=__LsbXHG_wX2SQdFjqVlLnL3aE3Lg=&h=788&w=764&sz=73&hl=en&start=4&um=1&tbnid=7LqGw_rB57Z2DM:&tbnh=143&tbnw=139&prev=/images%3Fq%3Dmarine%2Balternator%2Bwiring%2Bdiagram%26hl%3Den%26rlz%3D1G1GGLQ_ENUS284%26sa%3DN%26um%3D1

[ Edit | View ]

[> [> delco -- Randall, - Tuesday - 01/ 5/10 - 5:01pm

Yes. Am fairly certain it's the one pictured top middle--delco self exciting. Mine has the same shell and only two wires.

Still unclear how to ascertain its amp rating or how the regulator is to interact.

Still reading... :)

[ Edit | View ]

[> [> [> Some more reading for you... -- Paul - 1971 M31 - #106, - Wednesday - 01/ 6/10 - 1:56pm

After reading the article at the link below, you will understand that the alternator's output is not as much determined by how it's built, but rather by the regulator (internal or external).

The unrestricted amperage is (would be) direct proportional to the voltage drop between the alternator and the charged item. The regulator, however, restricts this flow by artificially raising the voltage the alternator "sees".

Per the article, one can trick the alternator into putting out a higher amperage by inducing a voltage drop. Note that by doing so, you could exceed the maximum design (sustained) amperage of the alternator and send it to Davy Jone's locker...

If you know for sure which alternator you have - make and model, you should be able to ascertain its maximum rated amps....

http://www.smartgauge.co.uk/alt_mod.html

[ Edit | View ]

[ Contact Forum Admin ]

Forum timezone: GMT-5
VF Version: 3.00b, ConfDB:
Before posting please read our privacy policy.
VoyForums^(tm) is a Free Service from Voyager Info-Systems.
Copyright © 1998-2019 Voyager Info-Systems. All Rights Reserved.