Alternator burnt up with 100 engine hours?!?

[steffan]

Originally Posted by Sam Woodbridge

I’ve also notice on a side note. Without shore power I’ve used the inverter - once the inverter is on the microwave light comes on. So, I thought let’s try it out. After running for 10 seconds it trips the breaker.

Sorry to hear about your alternator woes. It does sound like you have more going on than just that.

Regarding the microwave - what is its rating compared to your inverter? We have a 1kw continuous output inverter, which is supposed to allow for 2kw bursts. We thought we'd be OK to run a 700w microwave, but we experienced the same thing - it would run for several seconds then trip the inverter's protection. I used a Kill A Watt device, and a Victron Battery Monitor to determine that the microwave was actually pulling 1100w, which explains the tripping. We tried downgrading to a 600w rated model, which only pulls 950w, but it's still too much and eventually trips. We learned a lot and will go with a 2.5-3kw inverter on our next boat, which will also have a bigger LiFePo bank, vs the 200 Ah AGM we have now. In the meantime, the microwave gets used on shore power only.

[Lepke]

My powerboat is all AC except for nav lights, radios, instruments, and a few emergency lights. I have all the usual stuff you'd have in a house. My goal is to anchor for 2-3 days without running a generator. When I do run a generator, that's when I make water, do laundry, run the water heater, etc. During the 2-3 days, I use my microwave, 2 induction plates, desktop computer, tv, incinolet toilets, lights, reefer, freezer, etc.
The solution is enough batteries and a inverter bigger than 4kw.

[Mickeyrouse]

Regarding programming the voltage regulator (aka controller? ) Balmar has manuals you can download. If you can’t find it PM me with your email address and I’ll send you what I have.

As far as Balmar reliability, I realize set-ups, operating conditions and care of the whole system can vary boat-to-boat. I have been using Balmar alternators on various boats for about 30 years. The most recent installation was in ‘09. That unit ran for ten years before diodes failed. The local automotive shop repaired it for $75. However, I know that anything man-made will eventually crap out, so I picked up a spare on eBay with harness, sensors, and “smart” regulators, never used for cheap. Whenever I think we’ll be gone longer than the full charge on the batteries, I bring the spare along. And just to be safe, I checked with the repair shop to be sure that it was working as well.

[Sam Woodbridge]

Thank you Steffan, I just looked around and understand why the microwave runs for ten seconds. The inverter is only 700 watts. I’m not sure about how many watts the microwave is rated at yet.

Thank you also Lepke for your thoughts.

[Sam Woodbridge]

Originally Posted by Mickeyrouse

Regarding programming the voltage regulator (aka controller? ) Balmar has manuals you can download. If you can’t find it PM me with your email address and I’ll send you what I have.

As far as Balmar reliability, I realize set-ups, operating conditions and care of the whole system can vary boat-to-boat. I have been using Balmar alternators on various boats for about 30 years. The most recent installation was in ‘09. That unit ran for ten years before diodes failed. The local automotive shop repaired it for $75. However, I know that anything man-made will eventually crap out, so I picked up a spare on eBay with harness, sensors, and “smart” regulators, never used for cheap. Whenever I think we’ll be gone longer than the full charge on the batteries, I bring the spare along. And just to be safe, I checked with the repair shop to be sure that it was working as well.

Thank you for your reply Mickey, yes this morning I downloaded the manual for the controller. It was interesting to read. And I’ll probably go your route too and see if I can find my setup on eBay and keep it for a spare.

[AndyEss]

Sam - my boat is the black hole of alternators. If you can find a nice equivalent Balmar setup on Ebay, go for it.
I’d suggest going to an auto-electric shop and buying a re-built alternator (that fits your mount of course) that is internally regulated and self excited. The shop should be able to set you up with this for well less than $100 (US), probably less than $60.
This would be your WTSHTF backup to make sure you can keep your start battery charged, running lights going and your VHF receiving and trasmitting.
Wiring is dead simple - one wire to the battery, grounded through the mount.
Since heat is probably the killer of my batteries, I picked up a used, pretty cheap ($80) Porche or Audi water cooled alternator for my next experiment. I didn’t have the weight allowance in my luggage to bring it down with me on my last trip back to my boat (bought a Milwaukee right angle 1/2 drill to “electrify” my main halyard winch and this had priority) but am looking forward to more fun in my engine compartment running new cooling lines.

[FPNC]

De-rate the alternator by 15-20%. Connect Balmar alternator temp probe which will temporarily derate the alternator by 50% when it gets over 100° C. Most importantly, install a blower with a ducted hose to blow cool air over the alternator.

[Sam Woodbridge]

Originally Posted by AndyEss

Sam - my boat is the black hole of alternators. If you can find a nice equivalent Balmar setup on Ebay, go for it.
I’d suggest going to an auto-electric shop and buying a re-built alternator (that fits your mount of course) that is internally regulated and self excited. The shop should be able to set you up with this for well less than $100 (US), probably less than $60.
This would be your WTSHTF backup to make sure you can keep your start battery charged, running lights going and your VHF receiving and trasmitting.
Wiring is dead simple - one wire to the battery, grounded through the mount.
Since heat is probably the killer of my batteries, I picked up a used, pretty cheap ($80) Porche or Audi water cooled alternator for my next experiment. I didn’t have the weight allowance in my luggage to bring it down with me on my last trip back to my boat (bought a Milwaukee right angle 1/2 drill to “electrify” my main halyard winch and this had priority) but am looking forward to more fun in my engine compartment running new cooling lines.

AndyEss, thank you for taking the time to share your knowledge. I’ll get a back up as you described.

[Sam Woodbridge]

Originally Posted by FPNC

De-rate the alternator by 15-20%. Connect Balmar alternator temp probe which will temporarily derate the alternator by 50% when it gets over 100° C. Most importantly, install a blower with a ducted hose to blow cool air over the alternator.

FPNC, thank you - I will be getting it derated and someone else has suggested it too. I’ll be sure the temp probe is installed correctly. There is a blower inside in the engine compartment. I’ll take a look at that too.

Thanks again - Sam

[Stu Jackson]

Originally Posted by jack630

I would recommend going to marinehowto.com and read all the articles about batteries, alternators and regulators. It will make your head hurt but it's all there.

In addition, you could look here:


Electrical Systems 101 http://c34.org/bbs/index.php/topic,5977.0.html


Sam, what you've described is an inadequate understanding of your entire electrical system and how it all works together.


Take heart: we ALL started from that SAME POINT! None of us was born an electrician.


It takes time to learn this stuff.


Maine Sail's website and my collection of links, plus a book or two will get you started.


Good luck.

[BobFord]

I post this just in case it helps- My "bolt on " 24v Alternator (added for dedicated House charging ) would cook regularly. The cause was over heating , especially once engine off. Solution - a Blower that discharged cool air directly to alternator via ducting.

[Sam Woodbridge]

Originally Posted by BobFord

I post this just in case it helps- My "bolt on " 24v Alternator (added for dedicated House charging ) would cook regularly. The cause was over heating , especially once engine off. Solution - a Blower that discharged cool air directly to alternator via ducting.

Thank you Bob Ford, yes I’ll be looking into exactly where the blower is pointed in the engine compartment.

Thanks again Bob

[Sam Woodbridge]

Originally Posted by Stu Jackson

In addition, you could look here:


Electrical Systems 101 http://c34.org/bbs/index.php/topic,5977.0.html


Sam, what you've described is an inadequate understanding of your entire electrical system and how it all works together.


Take heart: we ALL started from that SAME POINT! None of us was born an electrician.


It takes time to learn this stuff.


Maine Sail's website and my collection of links, plus a book or two will get you started.


Good luck.

Thank you Stu, I’ll check out your links. And yes we all start somewhere.

[RaymondR]

The alternator overheating problem is generally cause because we take an alternator which is designed to recharge a single cranking battery, say 100 amp hours, and connect it to 600 amp hours of house batteries.

Alternator output ratings have a time limit which is as low as about 10 minutes and when used with a single battery the battery voltage will have increased and wound the alternator output back within this time limit. When we connect the alternator to a large bank of house batteries the wind back does not occur and hence the over heating.

In addition to connecting to a large bank of house batteries we often charge large banks with the alternator running relatively slowly and consequently being inadequately cooled because the fan is running slowly and not pulling sufficient air through the alternator to properly cool it.

The most fool proof solution to the cooked alternator problem is the temperature sensing control of output wind back one although I have sometimes implemented a temporary solution by placing a high wattage resister in series with the batteries in the alternator.

[Sam Woodbridge]

I was thinking about letting this thread go until I knew of a solution to my problem.But I have to mention.

** Alternator tested good **.

My problem is some where else. I’m better equipped with everyone’s help on the forums and with what I’ve learned from the local shop.

What I do know is. When my batteries are ran down (anchored out) for the first half in hour of running the motor. The no charging battery alarm comes on and off several times. If I where to leave the marina with fully charged batteries from being hooked up to shore power. There are no alarms everything works as intended. ** this is only happening when the batteries are low**

Anyways once I get it figured out I’ll be posting about it.

Thank you everyone for your input.

Sam