Backup regulator

[John Langford]

Many of us have installed external smart regulators with more powerful alternators. I was wondering if anyone had identified a suitable, inexpensive external auto regulator unit that might be used as a backup if the smart regulator failed mid-cruise. The previous smart regulator I had (made by Cruising Equipment in Seattle which was swallowed up by Xantrex, I believe) actually had connections for a backup regulator. I appreciate that the backup would not be "smart" but at least it would do the job until one could replace the failed unit.

The idea is that if I can identify and buy such a unit it and add it to my spares, it almost guarantees that my Xantrex unit will never fail:)

[Ron Hill]

John : You might want to call Xantrex and ask them that question or look in the literature that came with your Cruising Equipment voltage regulator.

The reason that I mention calling Xantrex, is because Balmar tells you that a Ford truck voltage regulator can be used a their back up (get you home) regulator.  The Balmar's wiring harness will plug directly into that Ford regulator !!

A thought

[Stu Jackson]

John,

Extremely good question and one I have been thinking about for quite some time, since Maine Sail has noted his bad experiences with external regulators.  I recently learned, on the C36 message board, that this was partly due to having them installed in hot engine room spaces.

That said, Maine Sail's the "go-to-guy" for alternators, AFIK.

While these may not necessarily answer your specific question, they're a good starting place:

Converting an Alternator to External Regulation:  http://c34.org/bbs/index.php/topic,4879.0.html

New Alternator Sources:  http://c34.org/bbs/index.php/topic,5686.0.html

[I got these thru a search on "alternators" by "mainesail"]

For backup purposes, your question is "What do I do if my external regulator dies and I want to charge my banks?  The alternator is just fine, but the regulator died." {when I'm not within hailing distance of a marine/electrical shop}

--- Buy a backup regulator with the Ford plug for the stator and field wiring.  Instead of an expensive MC-612 or MC-614, one could get a less expensive ARS-5 (while perhaps made by the same folks, everything I hear about Xantrex these days is not so good, so I'd go Balmar)

--- Buy a backup alternator with "standard" wiring with an internal regulator to get you home

One could make the point that if really "cruising" one would have a backup for both.  I recall Steve Dolling keeping his old OEM Motorola for his Mexico cruise, and needing and using it.  I was stupid enough to trash my old one when I bought my Blue Circle.  My next one will be a Leece Neville based on Maine Sail's recommendations.  Anyone who buys an overpriced Balmar, please, please, please, be warned that you might have better ways to spend your boat bucks.

In either case, it would be wise to have a pre-prepared wiring diagram for the minor changes that would be required to make the swap as easy as possible.  I know I did that with our glow plug solenoid project.  If (when?) my Ford solenoid dies, I am prepared to go back to the old wiring in about ten minutes.  I should also buy a backup solenoid!

--- Use the links above to figure out a way to wire your existing alternator's Ford connection to an "external" internal" regulator which you carry with you

I know I haven't thought it through and haven't specifically answered your question, but those are my current thoughts on the very good question you raised, and where I would start.  I've been thinking about it, too.  It would seem that with Maine Sail's "Converting..." article, one could simply revert to internal regulation by disconnecting the external (dead) regulator.

As always, the links withing those references may be helpful, too.

You could also pm Maine Sail (mainesail is the moniker he uses on this board for search purposes) and see what he has to say, perhaps mentioning and/or linking to this thread.

Hope you're having a good season, great to hear from you again.

[Ron Hill]

Guys : As You know I sometimes disagree with Stu !!

My Balmar has been in use for about 21 years.  I had to have the stator replaced (at 17 years of use) and the rebuild shop praised the great frame/alternator made by Listic with the Balmar name.

A couple of years ago I replaced my Balmar ARS III with an ARS V.  I made the post that I had it overnight shipped from Balmar in Seattle to Virginia cheaper than I could buy it at West Marine locally!!  Balmar gives their owners a discount.

Anyone that would mount an external regulator in the engine compartment is an idiot.  Just looking at the regulator, you can see it's mounted on a heat sync frame for better cooling!!  My Balmar regulator  wiring is long enough to easily find a cooler place than the engine compartment.  

I mounted my Balmar alternator immediately.  Not like some that kept there new hi output alternator in the box for years.

A Ford will go 70mph and so will an Acura.  You get what you pay for.  A few thoughts

[Kyle Ewing]

It seems if you're going to carry a backup regulator you should also carry a backup alternator.  Do regulators fail that much more frequently than alternators?  How about carrying an alternator with internal regulator as a spare as Stu suggested?

[mainesail]

Anyone that would mount an external regulator in the engine compartment is an idiot.  Just looking at the regulator, you can see it's mounted on a heat sync frame for better cooling!!

It's funny that there are many brands of regulators that hold up fine in & engine compartment, but some do not. Balmar did not begin advising against this for quite a while so there are still many in engine compartments that never failed and some that have failed. 

Interestingly enough our engine compartment has never exceeded Balmar's max temp for their regs, but I know some can. I had an ARS-4 fail on our own boat because it was installed incorrectly, in the engine room..

I have many customers with external regs in engine compartments, not Balmar's, and they survive ok but they are not water resistant units.. The current Xantrex (made by Balmar) & Balmar regs really should not be installed where temps can exceed 145F (Source - Dale @ Balmar). Balmar's regs are built to be highly water resistant/water proof and the epoxy used to pot the regulator needs to be clear so one can see the LED to program it. It is the epoxy that causes these issues due to high temps or rapid expansion / contraction due to rapid temp changes. Balmar is continually improving this epoxy whenever they can to be more tolerant.

That being said some of the older ARS series and earliuer MC series seemed to have a slightly higher failure rate. The newer units have been more reliable.

If I was world cruising I would carry a spare alt rather than a regulator as alts also wear out and you cover two bases with one device. The problem with this is many alt upgrades often involve re-working brackets and sometimes the old alt no longer fits. If the stock alt still fits you can carry it. An $8.00 Ford reg will work in a pinch but won't yield the same performance an ARS or MC will.

For installs I had briefly moved away from Balmar alts but then moved back. Rich, Rick & Dale and the crew offer excellent support! I still like the Leece-Neville alts, for the M25s as a drop in though.

Don't get me wrong Balmar is a GREAT company that does stand behind products but when I install a system for a customer, and the regulator goes belly up on their one week family vacation thus ruining it, it makes me look bad, not necessarily Balmar, and nothing I do can give them this time back........ :cry4

I was doing some Ample Power stuff but their attitude and net only tech support became infuriating, reliable stuff but very tough company to deal with and tehy totally lack teh programming capability that Balmar offers. I got a DOA reg and it took me three weeks of back & forth before they admitted the regulator might actually be bad. Meanwhile the customer is without a charging system...... With Balmar the issue is resolved in a few minutes on the phone.

I have also installed a bunch of Sterling stuff too but their regulator is again a very dumb version and can't compare to the Balmar.

AGM batts and their high acceptance rates have been a game changer and equipment that "never failed" has been failing.


PS Many of the older Heart Interface regs used the Ford regulator plug. If yours has it a quick trip to an autoparts store and you'll have a spare...

[John Langford]

This has been a great thread so far. Thanks everyone for your contributions.

I started from the assumption that I would have more trouble replacing a smart regulator than getting my Leece-Neville alternator fixed while cruising in rural British Columbia waters. Many smaller fishing ports will have someone who works on alternators but I suspect they wouldn't know what to do about a failed three stage external regulator.

I will ask Xantrex if they can recommend a cheap auto external regulator unit as a backup. Cruising Equipment is now history and their manual never specified a specific auto regulator that could be used in an emergency - so no help there.

I am intrigued by the idea of buying a backup alternator with internal regulation instead but it seems like a pretty expensive route to go...though no more expensive than buying a Xantrex or Balmar regulator as a backup. I will explore the Ford or equivalent voltage regulator option and check back.


I was puzzled by the Mainesail contention that internal regulation worked as well as "smart" external regulation if using flooded cell batteries. That is not my experience. After a night or two on the hook would an internal regulator put the boots to my batteries for a couple of hours until they were refilled? My e-meter told me that it wouldn't.

[mainesail]

I was puzzled by the Mainesail contention that internal regulation worked as well as "smart" external regulation if using flooded cell batteries. That is not my experience. After a night or two on the hook would an internal regulator put the boots to my batteries for a couple of hours until they were refilled? My e-meter told me that it wouldn't.

All internal "dumb" regulators and external "smart" regulators will full field the alt, read wide open, at voltages below absorption (absorption is the alternators voltage limit). All "dumb" regulators I have seen have enough field to run the alt to it's rated output. I have measured a Balmar MC-612 and a Leece Neville reg and both are at about 10.5+v and 5 - 5.5A when full fielding. Balmar allows you to limit the field, and reduce output, if you want to use "small engine mode" or their temps sensors...

Take two identical alts and a smart and dumb reg and both alts will be at max potential until the absorption set point is reached. If both regs are set to the same absorption voltage, and the alts are identical, both systems will charge virtually identically. There is absolutely nothing magic about full fielding an alt or "limiting" the voltage to 14.4v or so... Regulators are nothing more that on/off switches (bulk) and voltage limiters (absorption or float)... "Smart" ones do have some nice features that make a lot of sense especially with AGM or GEL cells. There are still many good reasons to use external regulation even on flooded batts but charging faster, all things being equal, is not one of them. Of course many older "dumb" regs were set to voltages well below 14v and you will never charge fast with one of these. Most alts made within the last 20 years are set to 14.2-14.6...

Most people never compare apples to apples and thus don't get an apples to apples comparison. They compare the new larger alt, with better low RPM performance, to a stock alt with diminutive wiring and a case ground that is often passing current poorly and even an internal regulator set to 13.8v. This is NOT an apples to apples comparison.  Contrary to popular myths "dumb" regulators do bulk and absorb just not float. Bulk is full fielding and absorption is voltage limiting.

For a more in-depth discussion here's the link:

Musings Regarding External Regulation
http://forums.sbo.sailboatowners.com/showthread.php?t=125392

[Ron Hill]

Guys : There was a nice alternator/voltage regulator in Sail magazine by Nigel Colder (sp?) in the July issue.  
It especially zeroed in on why your external regulator need a battery and alternator case temperature sensors.   A thought