how to connect MOtorola 30 amp alternator?

[ArtJ]

I have a rebuilt and stored 30 amp motorola alternator that has not been on the boat for a number of years.

I would like to bring in as a spare with me on a boat trip to Maine this week
in case I have trouble with the fancy stuff that I installed and need a backup.

I would appreciate it if someone could direct me to the proper way to connect
it. There is a push on terminal with short pigtail and two lug based connections at least.


Thanks very much

Art

[rigspelt]

Art, some of us have posted pictures and discussions of the Motorola wiring in archived posts. You might want to try a Search using rigspelt for example. Sorry - rushing off for a sail or I'd look them up.

[ArtJ]

I just browsed some threads.

Apparently, the yellow wire goes to the plus side of the coil,
The output terminal is obvious, and the ground connection I assume
is thru the case bolting.

The regulator terminal is occupied by the regulator already.
There is a ground terminal, but again, I am assuming that it receives this via
the bolt?

Art

[hanleyclifford]

Make sure that the "fancy stuff" does not include an external regulator unless you can and will bypass it in the event of using your spare which I believe does have internal regulation.

[ArtJ]

Hanley

Will do . By the way, in another posting you mentioned not recommending
external 3 stage smart regulators anymore. I would be interested in hearing
your thoughts on this.

Thanks

Art

[sastanley]

Art, If your stock Motorola regulator gives up the ghost, I found a bolt-on replacement that allows you to adjust the output voltage.

One of the problems with the stock regulator on the 35A Motorola is its output is only about 13.8 volts...way too low by today's standards for 12v systems. Compounding that problem on my boat is a passive diode type isolator, which ate another 0.7 volts. My batteries where only getting about 13.1 - 13.2volts. I have the regulator set to send about 14.9 to the isolator, giving me ~14.2v or so at the battery posts.

Hanley, I am interested too. I bought this $45 regulator instead of an external unit from Blue Sea,etc.. to keep my installation simple for now. If I were to get a fancier, i.e., higher output alternator if/when I need one, I'd look to get fancier charging equipment too.

Here is a link to the unit. http://www.ase-supply.com/product_p/trs-m5-197a.htm

[hanleyclifford]

Shawn - I understand your concerns about voltage. But keep this in mind: selection of alternator and voltage depend on how you use the engine. If you ran all day with the voltage you indicate, you would have boiled batteries. I run my engine 10 hours at a whack and therefore I set at about 13.5 volts. As for a new alternator, know that the stock accessory drive sheave will only support about 60 amps no matter how big an alternator you buy. Look at the charging curves from the Balmar catalogue. Too bad you Cat 30 guys cannot move your alternators up front like I did. All the best, Hanley

[sastanley]

Hanley...good points and I understand that long charge intervals would kill them at that voltage. I guess what I probably need is a smart charge controller, like the $75 Blue Sea unit.

I am usually running my motor as little as possible, runs up the creek are 50-60 minutes, or out to the bay about the same. :D

"Fancier " would be the 55 amp unit at Moyer, or similar. I have another 35 amp Motorola alt. as a spare though, and I only have one Group 27 house & a group 24 start battery. I have converted my anchor light and 80% of my cabin lighting to LED, so I don't really need any more juice!

[Dave Neptune]

Hanley, you seem to be one of the resident electrical gurus and I would like to ask you :o a question. I have thought of upgrading my charging form stock and just found a Motorola 55amp. alternator under a pile of dune buggy parts.
It is set up for an external regulator and I am looking for a recomendation for an adjustable one. I tend to motor for 5~7 hours to my mooring ~ use the batteries for a few days (no refer.) ~ start the lil beastie for safety and sail off the mooring then shut her down for the sail home. I again start her for about 15~20 minutes to motor into the slip. There she sits usually for 2 weeks and the process begins again. I do not use shore power or a battery charger unless I leave something on and kill the "House side" 2-235 AH golf cart 6 volts. Note my start battery is a deep cycle grp 27 which usually stays off line except for the run to the island.
I would like a bit more than the stock alternator provides as sometimes when staying for a week my batteries will get low and I would like to speed up the recharge process (motor to the Isthmus for dinner or drinks :rolleyes:) of which I seldom need or do.

Dave Neptune:cool:

[hanleyclifford]

If you have a 55 amp alternator set up for external regulation you have close to the ideal for your purposes. I think it was Jerry who posted the link to the adjustable regulator site. I would not use the multistage regulator. The multistage regulator is good for the boat that lives on a mooring, has lots of electrical demands, runs it's batteries down below 50%, and wants to recharge them in the minimum time without reaching over and turning that little screw and then remembering to turn it back after an hour of charging. I believe that the adjustable one voltage rate unit offers the best of flexibility, simplicity, and affordability.

[rigspelt]

If you ran all day with the voltage you indicate [14.2], you would have boiled batteries.
Hanley, I'm no expert, but is it not true that boat charging systems before the smart chargers and external regulators ran at 14.2-14.4 volts and apparently did not boil off batteries, or so I understand? Don't automobiles run at that voltage? Seems that many boats still run that way? I agree there is no need to run charging systems that high after an initial equalization charge, and that on cruising boats it makes sense to have a means to float them in the mid-13's, but I'm still unconvinced about the mid-14's necessarily overheating batteries in all installations.

Nevertheless, I would feel better if I could convert this API 55 amp alternator to an external regulator so I could dial the output back away from shore power. We have a smart charger for dockside charging.

[Mark S]

Rigsy,

At what voltage does your API 55 amp alternator charge through the internal regulator? I don't recall off the top of my head what my API does, so I'll make a note to do that, but I remember noting that it's less than 14 volts.

Mark

[hanleyclifford]

I would agree that 14.2 volts would probably be ok but Shawn indicated that he was setting at 14.9, losing .7 at the isolator (relying on it in effect to impose a fixed "regulation" on the system). I would not feel comfortable doing this and that is why I do not use isolators. The real question is - what voltage is actually being delivered to the batterys? Shawn indicated that his alternator was putting out 13.8 volts. I submit that would be fine if in fact it were being delivered to the batterys. In all probability he is losing voltage in the line as well as the isolator. Neil and I went around on this question of truck alternators putting out 14 volts with no apparent problem; but again, what is being delivered to the battery? Because I use maximum wiring in my system, I can deliver fairly close to alternator voltage to the batterys. When I set around 14 volts I have experienced fluid loss, and for this reason I have retreated into the mid 13 range.

[ndutton]

Neil and I went around on this question of truck alternators putting out 14 volts with no apparent problem;

To clarify, as I recall our discussion it didn't circle around a specific charging voltage but rather adjustable regulators vs. fixed ones. There's a popular belief that adjustable regulators are a better way to go, giving the operator more control.

Being old skool I'm not a member of that congregation. I figure the fixed output was determined by those much smarter than me and when countered with the suggestion of reduced battery life due to a fixed charge voltage I offered my truck charging system as an example of something that works well - - fixed regulation and many years of battery life.

Besides, I'm busy enough keeping my guests on domestic beer while keeping the imported stuff for me.

Footnote: the old skool fixed charging voltage for lead acid batteries was 13.8 volts, been that way forever before these young whippersnappers came up with all this new fangled electronic stuff.:rolleyes: I should add that my alternator has a fixed voltage regulator and my lead acid batteries are over five years old and counting with no noticeable reduction in performance.

[rigspelt]

Rigsy, At what voltage does your API 55 amp alternator charge through the internal regulator? I don't recall off the top of my head what my API does, so I'll make a note to do that, but I remember noting that it's less than 14 volts. Mark
Mark, it should be about 14.2 V according to the specs for that model. Mine seems to be charging at 14.6, which is higher than I would like. Took it to a reliable shop, but they say it's fine, and that they cannot set it lower. We are not doing any long distance cruising, so dealing with that is still on my back burner list.

[hanleyclifford]

Neil - I'm afraid that there are still some flies in your old "skool" ointment. First of all it is by no means certain that those who fixed the old charge rates were any smarter than you. Secondly, the old skool did not have to deal with the enormously complex electrical systems of today's cruising sailboats. Lastly, you have not addressed the matter of voltage losses from the alternator to the batterys which might be quite significant even in your old skool truck. BTW, a classy boat like the Catalina 30 should feature only the finest imported beer.

[ArtJ]

a friend of mine worked at APC American Power Conversion.
They manufacture battery back up systems for everything from
PC's to Large central computing systems.

Battery technologies used include wet lead acid , Glass matt and Gel types.

Each type has a special charging algorithm consisting of at least 3 stages.

One of which is float. I am not a battery expert, but they know what they
are doing with the smart regulators

One caviat was that if the batteries are not kept fully charged, they
deterioriate.
SO will our marine deep cycle batteries.

[hanleyclifford]

Art - All batteries will deteriorate in time but the one kept fully charged (without overcharging) will last the longest of all. Of course the batteries must be used for their purpose, and hence discharged; the first prize is therefore to discharge them as little as possible which then means having as many as possible to spread the load. It is also a fact that different types of batteries have different charging preferences. The "smart regulators", so-called, are really just devices for changing charge rates and setting charge periods, usually programable by the boat operator. Sometimes they have a "preset" program but I think they are still only as "smart" as the operator.

[ArtJ]

One other thought comes to mind, again, I am not a battery expert.

If a battery is allowed to remain discharged for a period of time
sulfation occurs (please don't ask me the chemistry). They can
sometimes be recovered by application of overvoltage higher than normal over
a specific algorithm, but it can be risky or dangerous to apply higher
than normal charge voltage. So it is best to not let the battery be left
in a discharged, or even partially discharged state for long.
Letting them get below 50 % is definitely not recommended by mfrs

Just an aside I happened to remember

[ndutton]

. . . . the old skool did not have to deal with the enormously complex electrical systems of today's cruising sailboats.

Huh??
Enormously complex??

What am I missing? Dealing with a variety of electrical systems daily, it's my opinion that it doesn't get much simpler than 12VDC, maybe a flashlight.

Anyway, that's my story and I'm stickin' to it . . . :D

[ArtJ]

In case anyone is interested

here is a link to a basic battery tutorial I just found. This is only one of many
including some more technical.

http://www.batterystuff.com/tutorial_battery.html

[hanleyclifford]

Huh??
Enormously complex??

What am I missing? Dealing with a variety of electrical systems daily, it's my opinion that it doesn't get much simpler than 12VDC, maybe a flashlight.

Anyway, that's my story and I'm stickin' to it . . . :D
Actually it does get simpler and I now know that I am an even older neanderthal than you - my boat formerly had gimballed kerosene lamps! Best Regards, Hanley

[roadnsky]

Rigsy,

At what voltage does your API 55 amp alternator charge through the internal regulator? I don't recall off the top of my head what my API does, so I'll make a note to do that, but I remember noting that it's less than 14 volts.

Mark

Mark-
I've got the AGI 55Amp and just did some voltage measurements yesterday as I continue to chase my hot Facet pump (another thread, another time)
Here's what the Alt is putting out on my vessel...

ALT: 14.28
BATTERY: 14.26

YMMV...;)

[roadnsky]

...I think it was Jerry who posted the link to the adjustable regulator site. I would not use the multistage regulator. The multistage regulator is good for the boat that lives on a mooring, has lots of electrical demands, runs it's batteries down below 50%, and wants to recharge them in the minimum time without reaching over and turning that little screw and then remembering to turn it back after an hour of charging. I believe that the adjustable one voltage rate unit offers the best of flexibility, simplicity, and affordability.

Here's the site for reference...
http://sterling-power-usa.com/advancedregulators.aspx

[hanleyclifford]

Jerry - Your low voltage loss between alternator and battery is most impressive. Can you tell us what sizes you use for the wire coming off the alternator (+ and -). Also what is your minimum size back to the battery? Thanks, Hanley

[roadnsky]

Jerry - Your low voltage loss between alternator and battery is most impressive. Can you tell us what sizes you use for the wire coming off the alternator (+ and -). Also what is your minimum size back to the battery? Thanks, Hanley

Doing this from memory...:rolleyes:
8AWG from the Alt to the Starter post.
8AWG from the Starter to the Isolator Switch.
4AWG from the Isolator to the Batteries

Short runs all of them.

EDIT: I looked at the wiring and the Starter to Isolator/Battery Bank is actually a 4AWG wire. (Not 8AWG)

[ndutton]

Voltage drop is a function of wire cross sectional area (in terms of resistance per unit length), wire length and current.

As the current increases, so does the voltage drop. Without excessive length, as long as the current doesn't exceed the wire gauge's rated ampacity the voltage drop is usually insignificant. Beyond the rated ampacity however, things start to get serious.

Depending on where Jerry's regulator senses battery voltage, the regulator may make up the difference.

The 8 gauge wire from the starter to the isloator switch caught my attention, not so much for charging but for starting. I've never measured it but does anyone know the normal amperage the starter draws? My former Perkins diesel starter could draw some serious amps, like in the neighborhood of 200 - 250 as I recall, maybe more. My battery cables were 4/0 just to address the starting loads.

Disclaimer: I'm not suggesting the A4 starter is anywhere near the Perkins in terms of starting loads.

[sastanley]

you guys don't want to know what I am running :rolleyes: (it was the biggest piece of wire I had on the boat when I eliminated the ammeter run to the cockpit in the middle of cruising.) :eek:

I think mine is 10 or 12 gauge..the run is short now though, about 24" from alternator to isolator, and then 4 awg from isolator to batteries..probably 12" & 16" runs respectively.

This setup is not permanent...it is only the beginning. I still have a random 14 gauge wire running thru the bilge that must be connected to ground on the house battery to make any of my 12 v systems work. I am guessing the "real" ground failed long ago.

[rigspelt]

The 8 gauge wire from the starter to the isloator switch caught my attention, not so much for charging but for starting. I've never measured it but does anyone know the normal amperage the starter draws? My former Perkins diesel starter could draw some serious amps, like in the neighborhood of 200 - 250 as I recall, maybe more. My battery cables were 4/0 just to address the starting loads. Disclaimer: I'm not suggesting the A4 starter is anywhere near the Perkins in terms of starting loads.
Not being an expert, I went through this decision-point for months before I settled on 4 AWG for start battery to starter (same as original on the boat for 34 years it seems), and 8 AWG for alternator output to starter solenoid B post (a foot; much shorter and larger than the old original #10 wire that had run from the alternator all the way aft to an ammeter in the cockpit ignition panel and ran both engine and house loads with #10 wires running forward again -- I scrapped those long runs in my refit). After digging up what I could, I got the impression that A4 starter draws are considerably less than 200A, perhaps less than 150A and normally maybe in the 135A range -- very easy to start. The concern is too small and overheating the wire, but I got the impression that too large can also be problematic for starter wires. Over normal short duration starter use (seconds), I thought that cable size could handle the draw in our situation, but of course a wrench left across the terminals for a prolonged period would be a different matter...

[ndutton]

Not being an expert, I went through this decision-point for months before I settled on 4 AWG for start battery to starter (same as original on the boat for 34 years it seems), and 8 AWG for alternator output to starter solenoid B post

Agreed. It seems the common wire size for our battery to starter circuit is #4. Jerry has some #8 wire in there that caught my attention. Regarding the alternator output wire, the standard alternator output is 35A max. and the common upgrade is 55A. #8 wire is capable of handling these maximums for prolonged periods and who ever sees their alternator operate at the max output anyway?

There are a few who have installed an alternator with a maximum capacity that seems beyond reason, yours truly being one of them. Replacement of the alternator output wire to a larger gauge is necessary in these upgrades. My original output wire for the Motorola 35A was #10. With my Delco 100A alternator the output wire is now #4.

[rigspelt]

There are a few who have installed an alternator with a maximum capacity that seems beyond reason, yours truly being one of them.
Just to clarify, we run the 55 amp API, which I am hoping I can somehow adapt to run with an adjustable external regulator.

[ndutton]

Sorry, worded my post awkwardly. 'Yours truly' meant me, not that your alternator was truly unreasonable. I had no idea what size your alternator was.

I'm the nut with the 100 amp alternator.

[sastanley]

I'm the nut with the 100 amp alternator.

Mmmm.... cold beer! :cool: - Neil, are you really up and thinking about this stuff at 5:00 AM local time? You and rigs are freaks of nature!

I will comment that the output wire on my 35A alternator is the same gauge as the orange wire that was originally in the charge circuit on the C-30, which as you well know, runs from the engine compartment to the ammeter in the cockpit and back, probably originally to the starter post. Once the isolator was added (who knows when?), the PO ran a (looks like 10 gauge also) from the ammeter directly to the isolator (+) post, which is back in the engine compartment, so the run was still just as long. I decided to eliminate the long 10# wire (& ammeter) for now, figuring that even though not ideal, the 10# run from the alternator directly to the isolator (+) post couldn't be any worse than the same gauge wire running all the way to the ammeter and back, as it had for xx years. Incidentally, the black wire running to ground and the (+) from the ammeter were exactly the same color and gauge & ran next to each other in the bilge. Getting anything to work on this boat & tracing P.O. nonsense while I contemplate the re-wire has been a challenge! :rolleyes:

[ndutton]

Mmmm.... cold beer! :cool:

That's right, ice cold beer, brain freeze cold.

For the record, members of dis here forum who visit are entitled to my private stash of imports. We'll leave the domestic swill for the common riff raff. My current preference is Pacifico Clara.

Actually, when visiting others and asked what my favorite beer is I reply with my 2 favorites: cold and free.

[ndutton]

I have thought of upgrading my charging from stock and just found a Motorola 55amp. alternator under a pile of dune buggy parts.


Dave,

Any alternator you use should be ignition protected. It's my understanding that automotive alternators are not. The attached pic of my 100A Delco shows the spark arresting screen.

[hanleyclifford]

Neil - Regarding your question about starter draw (post#27), mine shows 130amps using #2 cable. Also for the record I use #4 cable for alternator output, both positive and negative (110 amp Balmar model 712). I am relieved to learn of your splendid policy regarding beer discrimination.:)

[sastanley]

Bud Select 55 is currently $9.99 for an 18-pack here locally. That is only $1 more than the wretched Natural Light & Busch Light which I cannot drink.

I get my fill of imports when I go to the local mexican restaurant and drink the Dos Equis Negro (sp?) on tap in the 34 oz. mug! :rolleyes:

[joe_db]

Some comments:
Trying to charge batteries with a fixed voltage regulator is like trying to fill water balloons with a fixed water pressure. If you open the valve too far they will pop and if you open it only enough to not pop them they will take forever to fill.

That said, my experience with adapting modern regulators to the 55 amp Motorola is that the alternator gets driven way harder than it would be by the internal regulator and needs a diode or two replaced every 2 or 3 years. I think I need one now - the max charging current seems to have dropped a bit :(

[ndutton]

Shawn,

One of the great finds when building my Westsail in the 80's was cases of Meister Brau at the local Smart & Final for 12 bucks. There was a $10 rebate coupon inside, net cost was $2 for a case not counting recycle value of the aluminum cans.

Man, are we off topic or what??

[joe_db]

Is this the alternator you have?
http://cgi.ebay.com/ebaymotors/NEW-100-AMP-DELCO-MARINE-ALTERNATOR-MERCRUISER-1-WIRE-_W0QQcmdZViewItemQQhashZitem3f01538a1dQQitemZ27060 5191709QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccesso ries

Did it fit the A4 mounts?
Are you still using the internal regulator it came with?

Dave,

Any alternator you use should be ignition protected. It's my understanding that automotive alternators are not. The attached pic of my 100A Delco shows the spark arresting screen.

[Dave Neptune]

Niel, thanx for the heads up on the protection. Isn't the protection in the regulator that is chosen? I don't see any of the "spark" protection on the stock unit(?) and wonder what's up with it?

Ah swilling Beer I have a deffinate preferance but when offered a beer all I require is "wet and cold". Not to fussy unless the GUD stuff is available.
Save the "Ales"!:p

Dave Neptune:cool:

[ndutton]

Is this the alternator you have?
http://cgi.ebay.com/ebaymotors/NEW-100-AMP-DELCO-MARINE-ALTERNATOR-MERCRUISER-1-WIRE-_W0QQcmdZViewItemQQhashZitem3f01538a1dQQitemZ27060 5191709QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccesso ries

Did it fit the A4 mounts?
Are you still using the internal regulator it came with?

Yeah, that looks like the one. I had to modify the mount slightly by grinding off the corner below the pivot bolt to allow sufficient belt adjustment. When planning the installation I really struggled with the single wire concept but finally relented and installed it as designed, works great.

To answer your question directly, mine is internally regulated, single wire connection (output to starter post). Be careful with the connection at the output post, the spark shield is really close there and grounded.

[rigspelt]

Neil, are you really up and thinking about this stuff at 5:00 AM local time? You and rigs are freaks of nature!
Heh-heh - good company to be included within!

[ndutton]

Heh-heh - good company to be included within!

Yeah, often it's just me and rigs at that hour, sometimes Kelly - from France!

Neil, thanx for the heads up on the protection. Isn't the protection in the regulator that is chosen? I don't see any of the "spark" protection on the stock unit(?) and wonder what's up with it?

Dave,
This pdf explains it better than I ever could. Note that the alternators available from Moyer are all SAE J-1171 compliant.

[roadnsky]

Yeah, often it's just me and rigs at that hour, sometimes Kelly - from France!


Yeah...
but is it because you guys are up early OR just still up LATE?!;)

[sastanley]

Art,
Sorry we've gotten so off topic..did you get an answer to your initial inquiry?

I was snapping some pics yesterday and remembered I had a pic from 2009 of my Motorola alternator before I put on the aftermarket regulator.

the pigtail (yellow) is the exciter and heads off to the (+) on the coil.

the large black is alt. output to the charging circuit. Mine heads off to an isolator, but a common wiring set up is back to the starter as well.

[ArtJ]

Thanks Shawn for the information.

I managed to locate in previously, but your picture is great.

Thanks

Art

[Dave Neptune]

Niel, thanx for the pdf!

Where do you keep your boat? Do you ever get to Catalina?

Thanx Dave Neptune:cool:

[ndutton]

Dave,
I love it over at Catalina, particularly Isthmus Cove but alas, demands of work and family make those weekends all too rare. Hope to get over there later this month and I'll give you a holler before I do, would love to connect w/ you over there.

My slip is in Cabrillo, a little toward the outer harbor from 22nd Street Landing and in front of the Doubletree Hotel. That's 19.3 NM from the Isthmus!

For all youse non-West Coasties, I'm sure Dave will agree there's nothing like BBQ'n steaks in the cockpit as the sun sets behind the island after a 4 hour passage.

edit: OK, moved this business over to the Local Knowledge topic

[Dave Neptune]

Niel, I was actually the second boat in the new Cabrillo Marina when it opened and was there just over two months rent free:D, but that's another story.
I have a mooring in Emerald Bay and am a member of the Corsair YC, actually this year I'm the Commodore. I have four more trips planned for this season with the club. I will be in the Istmus next wednesday to drink some free booze:p at the Reef, the SCICo is buying for the Corsairs to celebrate our new lease:rolleyes:. Then I'll be in Emerald for the next week. Hope I don't miss Shawn's reports on the "Indigo" thread that starts out blaming me~~ouch.
Thanx for the info you provide. It is amazing how much "other" knowledge is gleened from this site and our precious lil beasties the A-4.
I might see/meet Hatch this weekend as the SS boat he is crewing will be racing just up the channel from my slip in Alimitos Bay~cool.

See ya soon maybe.
Dave Neptune:cool:

[sastanley]

Dave, don't worry...I'll bump the Indigo thread for you. :rolleyes:

Getting ready to head to the marina here shortly!

http://www.moyermarine.com/forums/showpost.php?p=25239&postcount=336

[Kelly]

Neil and Dave,

I used to sail out of Santa Barbara and Ventura before the French bug bit me. Catalina is very nice and much appreciated after a passage but I'm a bit of a hermit on the edges so my money goes on Santa Cruz Island. Nobody is out there but the gulls, rays, abalone etc.

There's something about dropping an anchor in an isolated cove and feeling like you're on the other side of the planet.

My 2 cents...