My '97 came with that charger, but it died a couple times and ProMariner replaced it with a ProTech 4, 4 stage charger. I use my boat similarly to yours, eg., 2-4 days away from the dock, with the fridge left on while plugged in at the dock.

I have an EMON-2 battery/charge monitor from Ample Power. When I arrive at the boat after it's been on the charger for several days, it reads a charge state of 100%. The amps indicator will be either 0.0 or some fraction of an amp. When the fridge kicks in, consuming about 5 amps, the charger compensates, and the net amp use goes back to about 0.

I'd think that would be the expected behavior of the charger, eg., it would sense the amperage being consumed by the fridge, and supply a similar amount back into the system. If your charger is still supplying 14+ volts, I'd suspect it's not functioning properly???? In my case, I have 11 year old 4D gel cells which are still going strong (charger is set to gel cells).

Long answer, which could be summarized that I don't think having the fridge on should cause a properly functioning charger to over charge the battery bank.

I have been experiencing the slow death of my charger.

I, too, run the fridge all summer and need a power source that both charges and is rated to run DC appliances full time.

How about an IOTA charger? They seem to enjoy a good reputation on the discussion groups. Do a search to see the opinions, on Sailnet for example.

[url]http://www.iotaengineering.com/dls.htm[/url]

Maine Sail himself suggests they are robust and very suitable for wet cell banks. They are also very reasonably priced.

Wire it to the house bank and use one of the bridging devices (EchoCharge or whatever) to charge your start battery.

A lot of cruisers carry a small Honda generator and use the AC output to recharge their batteries through the smart charger and avoid wear on their main engine.

This will be my next charger, get the available smart charger option "IQ4".

Cheers,
Graham

My Pro Mariner died in the first year, (2000). I replaced it with a Xantrex 40. Works very well keeping up with the frige on my 2 4D's, (house bank). When these batteries go, I'll move to the 4 x 6 volt.

Your charger is a POS. This is from 20+ years of C34 information and experience. One of our guys actually has had three or four of them and keeps getting new ones 'cuz he claims they discount the newer replacement ones. Wonder why he keeps having the same issues...

My experience with the ProMariner Flyback charger was that it blew up every spring, first time I turned it on..! For about 3 years straight... weird. They replaced it under warranty twice, then sent me the new/improved Protech charger, which has worked flawlessly ever since (except for a fairly noisy cooling fan). It's possible that the Flyback cooked and killed my flooded cell batteries, as I had to replace them after just a couple years of service (in 2000).

I don't know if the Flyback was just a crappy charger from the git go or what, but I can't fault the Protech.

[QUOTE=plaineolde;9955]

I'd think that would be the expected behavior of the charger, eg., it would sense the amperage being consumed by the fridge, and supply a similar amount back into the system. [/QUOTE]

This is one of the most oft-repeated incorrect statements about battery chargers that is made, many times. You're not the first, nor would you be the last.

The ACCEPTANCE of the batteries is what determines the charge rate. Think of the batteries as a great big BUFFER. Chargers are NOT smart (except when referring to the better 3 stage chargers for bulk, absorption and float).

The charger is putting out amps. The batteries will only accept so many amps based on their state of charge.

I tested this just the other day with our Link 2000, since I'd read so many of these claims.

The amp draw does go up when, say, your fridge turns on. The charge current does NOT go up to compensate. The charger is working off the battery acceptance, which hasn't changed significantly because of the relatively small load introduced by the fridge.

Chargers simply do not work that way.

When you install your Victron, try it yourself.

For further reading about acceptance:

[url]http://forums.catalina.sailboatowners.com/showthread.php?t=114054[/url]

The conclusions that Maine Sail notes, that are summarized by Balmar, apply to chargers, too.

[quote=gmackey;9965]I have been experiencing the slow death of my charger.

I, too, run the fridge all summer and need a power source that both charges and is rated to run DC appliances full time.

How about an IOTA charger? They seem to enjoy a good reputation on the discussion groups. Do a search to see the opinions, on Sailnet for example.

[URL]http://www.iotaengineering.com/dls.htm[/URL]

Maine Sail himself suggests they are robust and very suitable for wet cell banks. They are also very reasonably priced.

Wire it to the house bank and use one of the bridging devices (EchoCharge or whatever) to charge your start battery.

A lot of cruisers carry a small Honda generator and use the AC output to recharge their batteries through the smart charger and avoid wear on their main engine.

This will be my next charger, get the available smart charger option "IQ4".

Cheers,
Graham[/quote]

+1 for Iotas. We have a 55 amp one, it is the best charger I've ever had. I had a ProMariner ProTech4 in the last boat, it was flaky, never gave the same voltage in a given cycle twice in a row. Float voltage was all over the place.

The Iota in bulk pumps in amps until it can get the the voltage up to about 14.8, then it goes to acceptance at 14.3 for about 8 hours at a low amp rate, then it goes into float at 13.6 volts and picks up all loads up to 55 amps. It will do a mini-equalize cycle every 7 days to knock the sulfate off the plates. You need to get the IQ4 module to get that functionality, if you don't have that it is just a power supply.

The ProMariner Flyback 20-3 we had gave us many problems, too. I agree with the majority that a better charger is your best bet to solve your problem.

This is serious. My god, man, you could be talking about warm beer, here! :)

[QUOTE=deising;9988]The ProMariner Flyback 20-3 we had gave us many problems, too. I agree with the majority that a better charger is your best bet to solve your problem.

This is serious. My god, man, you could be talking about warm beer, here! :)[/QUOTE]

You could also be talking about a FIRE hazard, as one of our skippers found out.

[QUOTE=stu jackson c34;9971]This is one of the most oft-repeated incorrect statements about battery chargers that is made, many times. You're not the first, nor would you be the last.

The ACCEPTANCE of the batteries is what determines the charge rate. Think of the batteries as a great big BUFFER. Chargers are NOT smart (except when referring to the better 3 stage chargers for bulk, absorption and float).

The charger is putting out amps. The batteries will only accept so many amps based on their state of charge.

I tested this just the other day with our Link 2000, since I'd read so many of these claims.

The amp draw does go up when, say, your fridge turns on. The charge current does NOT go up to compensate. The charger is working off the battery acceptance, which hasn't changed significantly because of the relatively small load introduced by the fridge.

Chargers simply do not work that way.

When you install your Victron, try it yourself.

For further reading about acceptance:

[url]http://forums.catalina.sailboatowners.com/showthread.php?t=114054[/url]

The conclusions that Maine Sail notes, that are summarized by Balmar, apply to chargers, too.[/QUOTE]

Stu. Gotta disagree with you here, I think I have a pretty good grasp of how charging systems work. I read Mainsail's excellent article in your link, which is in line with my understanding. And in line with the basic electrical premise that volts are given, amps are drawn. I could have used better terms to describe what happens; the charger doesn't actually 'do' anything; my use of 'sense' and 'adapts to' weren't the best choices. The presence of a load, or lowered resistance, causes amps (current) to flow.

This is pretty easy to demonstrate, rather dramatically (eg., DON'T DO THIS). If you disconnect the chargers positive and negative leads while it's turned on, no current (amps) are flowing from the charger. Now if you touch those two wires together BIG spark and LOTS of current flowing. The resistance dropped from almost infinite ohms to zero ohms, causing lots of current to flow. If you'd touched the wires to a bilge pump, fridge or light fixture, the appropriate amount of current would be drawn.

Alternators and chargers don't vary AMPS, they vary VOLTAGE. When your engine is running, the alternator's output is controlled by a VOLTAGE regulator not an AMPERAGE regulator; the number of amps DRAWN by the battery bank is dependent on the internal resistance of the battery, which increases with the state of charge. When I start my engine to charge my pair of 4D gel cell batteries, the amps readout will be somewhere around 80-90 amps. This decreases to about half that, running the engine for an hour or so. It wouldn't matter if my alternator put out 1000 amps, the batteries would draw the same amount. As the charge continues, the voltage regulator will reduce the voltage according to the settings for bulk, absorption and float (and battery type). A good multi-stage charger will do the same, controlling the voltage.

Also, if the charger was not supplying current when the fridge kicks in, my batteries would be dead every time I arrive at the boat. If for arguments sake, the fridge draws 5 amps/hour, that's roughly 100 amps per day. With a 400 amp hour battery bank, it would be dead in 4 days. But again, using the volts are given, amps are drawn premise, if the charger is on, and has say 30 amps available, if the fridge DRAWS 5 amps, it will draw that amperage from the charger. Now, the charger is wired to the batteries, so it may be some average of the 2, I don't know exactly how that works, but if the charger is in the circuit, it will supply whatever amps are drawn from it, up to it's rating (30 amps).

I'm not trained in electronics, just practical knowledge gained from tinkering with boats, installing a charging/monitoring system, building electronic kits starting in the 60's (1st one caught on fire..!:eek:), and building/modifying tube guitar amps (which contain lethal 400 volt AC voltages). But I do think I understand this particular topic. I apologize if my choice of terms was confusing.

I agree! You're right. And a very good presentation of facts. Except for: [I][COLOR="Blue"]if the charger is on, and has say 30 amps available, if the fridge DRAWS 5 amps, it will draw that amperage from the charger. [/COLOR][/I]

Doesn't happen. The batteries are a BUFFER and...

The ONLY point I was trying to make was that chargers don't increase input amperage if a small load kicks in because charging is based on battery acceptance, not on the battery outputs, or perhaps, a better phrase: instantaneous load.

Think of it this way: batteries are full, charger connected, fridge kicks in --- charger does NOT go to 5 amps, it stays at float until the batteries are drawn down enough below the voltage, as you so well described, to enable the charger to revert back to higher voltage charging.

Chargers are dumb.

Thanks for putting that together.

Hi, Mike.

I am just around the corner from you at SYC. I also have 4 6V batteries, but replaced the original charger with a Xantex after 2 failures under warranty. Properly maintained, the golf cart batteries should last longer than 5 years. I also anchor out in the island for 2 or 3 days and when I do, I backup the main bank and take along a portable jump start unit large enough to start the diesel.

Contact me to get together next season!

Mike, before you even consider AGMs, please read these posts from Maine Sail:

[url]http://forums.catalina.sailboatowners.com/showthread.php?t=124973[/url]

and

[url]http://forums.catalina.sailboatowners.com/showthread.php?p=848465&highli...

[QUOTE=mogline;10883]Hi Gene,
I'll keep an eye out for you next season. Update on my battery issue. After checking each cell and finding several bad I decided to scrap the batteries after we hauled out. Found the case was bulging on 2 of the 4 (bad sign). I'm pretty good about checking water level, never letting them get too discharged, etc., so decided to replace the Flyback with a Charles 2000 SP 30 amp. Not sure exactly why except I couldn't identify any other problem. Came close to the IOTA but just didn't trust a non-marinized unit. Unlike most projects this one was easier then anticpated. Right now I'm stuck on going with 4 T105s or AGMs. Cost vs. quicker recharge. Here in the soon to be frozen north its nice to have something to worry about all winter.[/QUOTE]

Mike,

Next to Xantrex & some Pro-Mariner's the chargers I replace most are Charles. The one on our 2005 Catalina failed twice under factory warranty!!

If you can still return it you might consider a Sterling Pro-Charge Ultra, Mastervolt or Victron. I really like the Sterlings as they offer the most features and flexibility and they are really well designed and engineered. Despite the Iota's not being "marinized" they have proven to be a heck of a lot more rugged than Charles, Xantrex or Most of the Pro-Mariner units I see fail on a fairly regular basis...

With a 450Ah bank of wets, at 25% acceptance, on a 90A alt you simply do not even have the ability to max out the acceptance of the wets let alone the AGM's.

A 450 Ah bank of wets can accept about 112A in bulk and you have a 90A alt, which when hot, will put out 70A +/-.... You will not charge any faster and this is a common misunderstanding when people already have large banks of wets. You will however drain your wallet faster by switching to AGM's.........:D

You also don't need to spend the money on Trojan's. Most Sam's Clubs now sell Deka/East Penn Batteries. The 6V EGC2 is a 230Ah battery and costs about $84.00 +/-... Depending upon your area this can be about half what a T105 sells for. The Deka's sold by Sam's are the SAME EXACT batteries West Marine sells only for about HALF the price. The only difference is a Duracell sticker rather then a "Sea Volt" / WM sticker..

I am really glad we have folks (like Stu and Maine Sail, and many others) who will step up and try to re-educate the masses on various issues.

It can be very easy to be led astray by manufacturer hype, catalog descriptions, or uninformed 'dock talk.' The devil really is in the details much of the time.

Proud to be a part of this great group!

If you are topping off with distilled, the batteries are coming to the end of their life. When I bought Hilbre, she was just two seasons old and had Exide 2x 4D wet cell batteries held in place by 2 2x4 pieces of wood. Everything looked good but as I worked through maintenance and checking all the items on the boat, I noticed that I was using a lot more distilled water than I should. I bit the bullit and bought 2 Wet Cell 4D Batteries from WM, not wanting to change out the Charles charger which was only capable of regulating for wet cells.
To my horror when I pulled the 2 2x4 pieces of wood out to replace the batteries, the underside of the wood had turned to CHARCOAL! The message here is do not mess around if your batteries cannot hold a charge, they are and can be a real fire hazzard.
BTW the 2 WM Batteries lasted me five years with loving care and still doing strong, I only replaced them because of going to Mexico. With care, good maintenance and monitoring, batteries should last their rated life.
John Meyer
Cruising Mexico

John,

The wood hold-down bar had a similar 'charcoal' appearance when I had vented flooded cell batteries, too. I never attributed it to excessive heat, but rather the effect of the acid fumes over time.

I do not have time to research this now, but I can't imagine that you would have had enough temperature to charcoal wood without burning the insulation off the cabling.

Let's not consider this 'case closed' without more follow-up.

This was bugging me, so I found this about Sulfuric Acid [url]http://www.hillbrothers.com/msds/pdf/sulfuric-acid-eg.pdf[/url]

[Here's an excerpt:

Section VII - Handling and Storage

...This product has a great affinity for water, abstracting it from the air and also from many organic substances; hence it will char wood, etc....]

The charring of wood is basically a removal of volatile compounds and moisture (water) in the absence of combustion, so the acid fumes may be doing just that over time.

Duane
Thanks for the research, there is often a different angle. All I can say is it scared the heck out of me and I installed a battery temperature monitor as a result. It now makes sense there may be some wicking effect from the battery acid. When I changed the batteries in October, there was no sign of any charcoal effect, in fact, everything was nice and clean. It may have been that I was burning off enough water/acid from the batteries the first time I changed them. It was good to hear I was not the only person who experienced this problem.
John Meyer
In La Paz - Cruising Mexico

It is true that if you place a load on a battery that is charging that the charger will not supply the additional required current - immediately. The best word I can use is explain is "hysteresis loop". If you are familiar with this then this is what I expect that it will happen. So the additional drawn current will not immediately step up the current from the charger - instead after the battery starts to discharge then the charger will increase its current ( due to higher voltage) to bring up the battery to its normal voltage - then drops back again.