Battery B.S. Again

[Mike D]

Yes it is true. I am having battery issues again. Last year I installed an 8D for my house bank. I already have a Group 27 for my Starter. They are both gels.I have replaced the original charger that burned out with a True Charge 20+. It has a remote panel and a remote temperature sensor.The batteries do fine on the charger.On my recent trip though, the house battery would not charge up even with much engine time. The boat is a Hunter 376 1998 with a Yanmar 50 amp internally regulated alternator. Hunter used a solenoid relay to combine the batteries when the engine runs to allow both to charge from the alternator. There is no other crossover and each battery has an independent off / on swith.After running most of the day, we anchored out and my house battery only lasted an hour or two. The next day I ran my generator and charged it. During the day motorsailing, I was getting a low voltage alert on my vhf.I checked and had voltage around high 13's on both batteries. I am thinking that the starter battery is triggering the alternator to slow down prior to the house battery charging. Also, the gel house battery had a removable cap so I peeked in. The gel was solidified on the top and looked like hardened and cracked wax. I switched my 8D back to the original 4D and had similiar results with a low voltage alarm while motoring.Has anyone had any similiar results or know who I can consult to get expert opinion or diagnosis. We are in the Chesapeake on Maryland's eastern shore.Mike D

 

[Fred Ficarra]

Mike, what immediately comes to mind is your

regulator. Any 'standard' 'stock' regulator will take about 10 hours to charge your battery from a significant discharge. These are basically automotive chargers. If you are using a standard regulator you should explore a marine regulator designed for your system. Voltage can be set at mid 14s and amps can be also maintained much higher than 'automotive' regulators. Safeguards are also available to protect the alternator from excessive heat caused by high charge rates. The only thing not accounted for is drive belt capacity. It might slip and burn up.

 

[Miles8313]

Bad connections?

it sounds like you measured voltage at the batteries in the high 13s which is normal. Also you had the same low voltage problem with your old 4D. I wonder if you don't have a bad connection or some corrosion with added resistance on one of the connections somewhere. You also might want to measure the voltage at the VHF if you can. If the voltage at the battery terminals is 13+ but it's low further out in the wiring then you probably have a connection issue.

 

[Stu Jackson]

Fred's Right

An internal regulator is just an automotive regulator and is NOT charging your house bank. The house bank needs lots of amps at 14.1 or 14.2 volts for bulk charge to start with, then absorption, then float stages. All you get with an automotive regulator is a tapering charge of steadily reduced amperage at a constant 13.8 volts. Goin' nowhere fast.Any good electrical marine book will tell you about this in great detail, without us copying it here. Try Calder's Boatowner's manual. You could run your engine all day and still not get much charge.You need a smart external regulator and a larger output alternator.You should also check why your battery only lasted an hour or two after the Truecharge was working.Miles is also right, when it comes to electrical check the connections. All of them.Stu

 

[Mike D]

Thanks for the advice!

Thank you all for your input. I did read the tech data on the proper setup for the alternator and the external regulator. I guess I am just awed at how this was supposed to work when Hunter installed the engine and the battery banks and the charger. Basically the entire system.I am not sure how I should feel but it sounds like this never had a chance to work properly as provided by the factory. I guess when I think about it I feel that since it was never capable out of the box, Hunter/ Dealer really owes me a system that works. This should be regardless of the age of the boat. I am sure that I am missing something here! Please feel free to comment. I would love to hear fellow boaters' opinions on this.Thanks again for the help,Mike D

 

[Jeff M21319]

Why would a manufacturer provide....

such a system? From what you've described, this charging system sounds like it was doomed from the start. Use a relay to combine a group 27 and a 4D to a single automotive style alternator and expect them to both be properly charged? Never gonna happen. What I'm wondering is, why would such a reputable builder as Hunter provide such a goofball setup on such an important system? Is this typical of all the builders? Do they simply figure that once you get the boat that it will be your problem to install a proper charging system? Is the rest of the electrical system also this marginal? What about the other systems in the boat, ie. fresh water plumbing, holding tanks, fuel system, propane, etc. Are they installing just enough equipment to say it's there, or do they include a truly well put-together system? Is this sort of thing only found on the Hunters (which I always thought was supposed to be a fairly 'high-end' boat) or do other builders do the same thing? A lot of questions (sorry!) but the whole thing just doesn't make sense!Hope somebody has some answers,Jeff

 

[Rick D]

Jeff and Mike

I believe the standard is to provide only a basic electrical storage and charging system from the factory on production boats. It is up to the owner upon commissioning or later to add such additional equipment and storage capasity as they desire. In some respects, that makes more sense since there is a lot of variety and the owner can make a choice best suited to their needs and bias. Rick D.

 

[Chris Burti]

An Observation from this Idiot's Corner!!!

Please let me preface my comments by stating that I hope I don't start a firestorm of controversy. That I am not disputing the technical data and combined wisdom of some very knowledgeable and experienced sailors and engineers. Nor, am I castigating anyone, questioning their intelligence, veracity or character. I even have sufficient education and experience in electronics to have read these posts and countless ones like them with great dismay at the expense and effort I saw as inevitable ever since I first started joining these lists.However, I personally tend to be an inveterate procrastinator and unconscionable cheapskate. The following is NOT a justification of those traits. It is CERTAINLY NOT a recommendation. It is simply my personal experience with a factory setup.Our last boat had a couple of multi-purpose batteries for the house and for starting an outboard that had a 9 amp output charger. Never did get around to installing the hard wired charger I bought, even though we typically anchored out. The little bit of motoring we did, produces enough charging current to exceed our consumption, modest as it was.Now we have a 2001 Cat 320 with all the electron gobbling goodies. We have the OEM batteries and OEM 55amp Yanmar alternator/regulator and OEM fly-back (so frequently castigated) charger. We run the reefer 24/7/360. We can sail all day with heavy use of the autopilot, radio and instruments, anchor all night with the anchor light on and run a couple fans (including one 110 v. on an inverter) on a single battery and it will just approach or be in the yellow in the morning.Next morning, I fire up the diesel to test the battery, shut down the engine, switch to 'all', fire her back up, put her in reverse to load her and crank her up to about 1500 RPM. One hour and twenty minutes later...both batteries are in the green and we'll use the alternate battery for the next 24 hours. Been doing this for about fifteen months now and all has been fine. I don't have the "cooking" problem associated with fly-backs...takes about a pint to top them off ever six months.It is important to note that I have never discharged either battery to the point where it alone would not start the engine.It may be an aberration, I may be as lucky as one can get...the whole system may go toast tonight. But, I've moved upgrading the charging system way down on the priority list. I don't plan to move it up until I have a component failure. I do think that common sense dictates that I go with the common wisdom and experience by purchasing and installing upgraded equipment instead of just replacing with the same at that time.