Alternator problems

May 4, 2012
47
Hunter 45DS Toronto
I had a Balmar 165 amp with an external Balmar 615 installed about a year and a bit ago. It was fine but we motored just to get out of the marina. This year we went on a long trip for our vacation and did not always have much wind, so we motored for long hours. On the 1st day after 3-4 hrs of motoring, I noticed none of of the engine gages at the helm were not working (temp, tach, pressure) the engine ventilation blower was not working as well. I went to the nav station and found that none of the batteries were charging, I opened the engine compartment and there were no lights on the regulator. Then I checked the breaker at the battery and it was tripped so I reset it and no improvement. So then I ran the generator until we got to our next port.

The next day everything was fine again?

A few days later I was about to leave the dock and my wife smelled something burning. I opened the engine compartment and the alternator was very very hot and burning. The wires were melting and the smoke alarms went off. My batteries were reading 11 volts and dropping. So I disconnected everything and it cooled off.

I took the alternator into an alternator shop and they said that the alternator was completely melted inside. Windings, bearings, everything.

I went back to the installer but they seem elusive. So I don’t know if this is an installation problem or a defect in the alternator or the regulator.
Has anyone had this problem before? What did you find?

murray
 
Sep 30, 2017
69
Hunter 34 Gunpower Neck - Aberdeen, MD
sounds like a busted regulator. call Balmar, I have found their tech support to be excellent
 
Dec 28, 2015
1,837
Laser, Hunter H30 Cherubini Tacoma
Check all of you main leads from your battery. Tripping the main battery breaker/fuse is a significant draw. Something is loose or crossing. Do you have a external temp sensor on the alternator and battery? If so then there may be a issue like described above and a issue with the ext. regulator. It should have saved the alternator from over heating. This is assuming it melted because of over working and not getting shorted out. How long have the system been installed?
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
We'll need more information..

How big is the battery bank (Ah capacity)?
How low do you discharge it? (11V is grossly over-discharged and can work an alternator really hard)
What chemistry is the battery bank flooded, AGM, GEL, LiFePO4?
How was the regulator set up/programmed?
Where was the alternator temp sensor connected?
What "breaker" tripped? (alternator B+ should be a fuse within 7" of bank + at 140% to 150% of alternator output not a breaker)

Can you post or link us to a photo of the installation?
 
Jun 1, 2009
1,735
Hunter 49 toronto
We'll need more information..

How big is the battery bank (Ah capacity)?
How low do you discharge it? (11V is grossly over-discharged and can work an alternator really hard)
What chemistry is the battery bank flooded, AGM, GEL, LiFePO4?
How was the regulator set up/programmed?
Where was the alternator temp sensor connected?
What "breaker" tripped? (alternator B+ should be a fuse within 7" of bank + at 140% to 150% of alternator output not a breaker)

Can you post or link us to a photo of the installation?
If the alternator was cooked, I believe that the output diode (rectifier ) failed into dead short.
The rectifier allows the alternator to output Dc voltage, but blocks the battery from back feeding the alternator stator.
Pretty sure this was your failure
 
Jun 15, 2012
694
BAVARIA C57 Greenport, NY
I upgraded to the exact same Balmar system around 3 years ago and have not had any issues. From the original post we know the alternator is cooked. I would want to test the 615 because if it was working and installed correctly I would think the temperature sensor on the alternator should have shut down the alternator.
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
If the alternator was cooked, I believe that the output diode (rectifier ) failed into dead short.
The rectifier allows the alternator to output Dc voltage, but blocks the battery from back feeding the alternator stator.
Pretty sure this was your failure
A rectifier failure would be extremely rare in this series alternator. Balmar is using avalanche diodes in these and they are way over-sized. A more common failure is it being over-heated due to the regulator not being set up correctly for the bank..
 

TomY

Alden Forum Moderator
Jun 22, 2004
2,758
Alden 38' Challenger yawl Rockport Harbor
Sorry for the thread drift: My ARS-4(5?) gave out while out for a few weeks. Luckily, I still had an old Ford voltage regulator from when the last AR-whatever, quit.

That got us through. With a little solar, we don't discharge the batteries much. This dumb regulator has no ramp up so it's tough on belts.

Other than that, it does 95% of the smart regulator for our needs, by my accounts.

I'm curious, is there an alternative these days for a simple voltage regulator that will last more than 8-10 years?
 
May 4, 2012
47
Hunter 45DS Toronto
Check all of you main leads from your battery. Tripping the main battery breaker/fuse is a significant draw. Something is loose or crossing. Do you have a external temp sensor on the alternator and battery? If so then there may be a issue like described above and a issue with the ext. regulator. It should have saved the alternator from over heating. This is assuming it melted because of over working and not getting shorted out. How long have the system been installed?
I am going to the boat tomorrow and will check the connections. Installed 2 years ago but this was th3 first time running for hours on the engine.
 
May 4, 2012
47
Hunter 45DS Toronto
We'll need more information..

How big is the battery bank (Ah capacity)? 600 amp
How low do you discharge it? (11V is grossly over-discharged and can work an alternator really hard). The alternator was shorted out and drawing from the batteries, as soon as I saw it I disconnected the battery
What chemistry is the battery bank flooded, AGM, GEL, LiFePO4? Rolls 4D’s 555 amp
How was the regulator set up/programmed? Yes for flooded batteries
Where was the alternator temp sensor connected? Yes
What "breaker" tripped? (alternator B+ should be a fuse within 7" of bank + at 140% to 150% of alternator output not a breaker) the breaker was installed at the battery as a fuse

Can you post or link us to a photo of the installation? Will get pictures
responses in bold above
 
May 4, 2012
47
Hunter 45DS Toronto
If the alternator was cooked, I believe that the output diode (rectifier ) failed into dead short.
The rectifier allows the alternator to output Dc voltage, but blocks the battery from back feeding the alternator stator.
Pretty sure this was your failure
what could cause that
 
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
responses in bold above
What size was the breaker? Brand & model? Fuses should be used for this application, not a breaker, at 140% to 150% of the alt output rating. 140% is 230A and 150% is a 250A fuse.. Blue Sea systems does not even manufacture a breaker large enough for an AT165. Thermal Type breakers should really not be used for an alternator application Only MRBF, ANL or a Class T fuse....
 
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