Question concerning a 30amp plug charging a 230volt system

[sail2bluesue]

Hello,
We have a Jeanneau 43' Sun Odyssey DS and currently live aboard in Mexico. We have a 230V panel, and the shore power plug is a 30amp plug. We have two banks of batteries, and two Xantrex battery chargers. We also have solar and a generator.

The problem - We are having to replace our 8 AGM house batteries after only 4 years. We are being told that part of the problem may be that the shore power charging amps are not sufficient for the 230v system, so we have been undercharging the batteries when on shore power (which isn't too often). However since both the shore power plug and the circuit board were installed by the manufacturer, we're having a tough time processing this in our electrically challenged minds.

Does anyone have any input about whether 30amp shore power is not sufficiently charging our batteries? Should we have a higher amperage shore power for a 230v system?

Any info is appreciated!
Thanks,
Sue and Marty McDaniel
s/v Happy Dance

[edsailing]

More likely a problem with the charge voltage regulation, what voltage do you see when charging? You should be seeing 14.4v to get them up to full charge.

If you aren't on shore power very often, it's unlikely that it is the problem.

[zeehag]

ok here is what i see to be your issue. you have 240 v system, yes? which SHOULD be charged with 240v compatible system, correct??
30 amp is 120 v. perhaps that could be your problem. most of the megas and yachts i have seen with 240 use 100 amp shore power or 2 of the 50 amp hookups.
good luck.

[sail2bluesue]

To answer the two replies below...

The circuit panel and all the documentation from Jeanneau shows that the system is 230v, however we've learned now that it's actually a 115v system based on the actual circuit breaker.

When we charge the batts via the alternator, generator or shore power we see 14+ going in.

So it seems that 4 years may just be the limit on our batteries even though we'd hoped for longer. As one guy said...the batts are in their death spiral..ha.

Thanks again!

[Sailmonkey]

are you sure you've got 230 volt shorepower? typically that would be a 32 amp inlet if wired for european power.

If you have a 30 amp inlet, you've got 120 vac.

either way, your incoming current will not prevent your batteries from charging. it will however limit the size of the charger you can use.

I would be quite surprised if this is the case.

However if the charging sources were not optimized for your AGM batteries.....you have most likely murdered them, either by under or over charging.

[skipmac]

The problem is NOT the shore power. Not clear from your post if your boat has a European system, 50 Hz or a US system that is 60 Hz. Either way, if you convert 100% of the shore power to 12V to charge your batteries you would have several hundred amps. 30 amps AC (alternating current) on any system, if functioning correctly, will have enough power to charge the batteries on several boats IF converted to 12V DC.

The question is, what is the size of the battery charger? You understand that the shore power has to be converted to 12V DC to charge the battery. You have plenty of shore power but how big is the battery charger.

The next issue, AGM batteries can be very sensitive to how much and how often they are charged. AGM batteries in general need to be fully charged on a regular basis, at least a few times each month is best for long term battery health. If you are seldom on shore power, don't have a large solar panel system or other means to fully charge the batteries then very likely your AGMs will die a very early death.

Unless you have a way to properly charge and maintain AGM batteries and an understanding of how to care for the batteries you will do much better buying standard FLA (flooded lead acid) batteries. The most reliable, most tolerant of abuse and also the least expensive are 6V golf cart batteries. The size code is GC2, available from many sources. Trojan is a well known, high quality brand but there are several others.

[Stu Jackson]

AGM Batteries - Making The Choice (from Maine Sail)

https://forums.sailboatowners.com/in...choice.124973/

AGM Battery Issues and the Blue Seas Dual Circuit Switch (from Maine Sail) "DARN AGM Batteries"
https://forums.sailboatowners.com/in...teries.133773/

Additional Observations on the Limits of AGMs Electrical Systems 101

[edsailing]

One critical factor on battery life is how low and how often you discharge them.

It's generally accepted that letting the voltage get below 12v will shorten their life.

Also, if one battery is dud, that may stop the others charging correctly and the bank will lose its charge quickly.

I'd suggest getting each battery tested using a discharge tester,make sure all connections are good, clean and tight and if that doesn't work get an electrician in.

[skipmac]

Originally Posted by sail2bluesue

To answer the two replies below...

The circuit panel and all the documentation from Jeanneau shows that the system is 230v.

We have been told that 30 amp only charges 120v, so why would Jeanneau install a 30amp shore power outlet?

When we charge the batts via the alternator, generator or shore power we see 14+ going in. The batts are no longer holding that charge though...thus the need to replace. We're just trying to figure out what may have caused this issue.

Thanks again!

Hi Sue,

I may be confused but it appears from the context of your posts your understanding of electrics is a little fuzzy.

Are you clear that there are two very different kinds of electricity on your boat? There is shore power which is AC (alternating current) that could be 110-120 V (in the USA) or 230 V (Europe) or 220-240V (USA).

You also have DC (direct current) which is what your batteries use which is in most boats 12 V. This is like the electricity in your car.

Voltage is electrical pressure, like PSI is water pressure. Amps are how much electricity is flowing, like how many gallons of water is pumped.

To charge batteries you have to convert the shore power AC to DC power that the batteries use. In very, very approximate terms one amp of shore power will convert to 10 amps of battery power. So your 30 amps of shore power could convert to 300 amps or more of battery charging.

Again, the issue is more what size is the battery charger, that is how much of the shore power is converted by the charger to 12V DC for the batteries?

[mcm]

Are any of the appliances etc working on the boat when plugged into 30 amps

Does your panel have indicators which show voltage on both legs of a 240 input, if so it may show only one leg with 120 v and your charger may not get anything.

Does the boat have a voltage converter 120 splits into 2 legs but giving only 15 amps ea leg ?

[sailcrazy]

If you're sure you have a 230v system, then your situation is very similar to ours. Our boat was built in Asia, for the Asia/Europe market, and has a 230v, 50Hz, 3-wire(hot, neutral, and ground) AC system. and we run all shorepower through a Victron auto sensing Isolation transformer- before it goes to our boat's AC system. That way our ship's AC systems only, ever, see 230v AC. Typical Asia/Europe shorepower is 16Amps at 230v (and VxA=Power; 230x16=3680watts). That is roughly equivelent to the US standard of 120v 30amp shorepower, although US standard is 60cps vs 50 cps European power (120x30=3600watts). Most modern battery chargers can accept either 120v or 230v AC power, at either 50Hz or 60Hz input power, and output 12v DC power to the batteries. The max output DC amps, however, is dependent on the charger model you have, but EITHER shorepower will certainly be enough watts (power) to properly drive the charger. IF your boat is set up for 230v European power, then you must have a transformer in the system to convert the 120v US power into 230v European power for your boat's sytems, assuming it can accept the 60cps power frequency. And if you try to connect US 240v power....that's a 4-wire system, and totally different from your 120v (3-wire) or 230v (3-wire) system. Bottom line.....your shorepower inlet (120v or 230v) is almost certainly enough power to drive your battery charger. Perhaps it's worth it to get an electrician onboard, find out exactly just what you do have, and confirm your charger is properly connected/powered.

[FionaJC]

If your batteries charge ok on the engine then they are not EOL. if they dont fully charge on shore then your charger is suspect. You can use a multimeter to see the voltage if you havent got a battery monitor, they are great as they show the state of charge.

Charge them and then put a 12v load on, for us its the inverter and microwave. If the voltage dives well below 12v then they aren't holding their charge and are EOL.

[waterman46]

Sounds like you dont have a proper battery monitor, one that tracks amp hours and shows voltage and current in and out of your batteries. If not, get a good multimeter now and add the monitor when you can. As a start, simply monitor your battery voltage during charging from shore power with your present setup. From a discharged state, battery voltage during charging should rise to over 13V within a few minutes. After an hour or so you should be up to around 14V.

Thats very very general and you need to read the manual for your charger and know the capacity of the battery bank and its state of charge to get more accurate. But if you dont get voltage over 13.5V then something is wrong wirh your charger or its not powered up correctly from shore power.

Sounds also that you could be benefit from discussions with other cruisers in your area.

[Moontide]

First, 30 amops is more than enough. Could run most ac off that amount of power.

Need to determine if you have US or European 220 system. Euro is 3 wire - hot (240), neutral and ground. US is four wire = Hot1 120, hot2 120, neutral and ground. Easy to check yours with a voltmeter. My boat is US 240 so half the 120 side runs off one leg of hot, other half off second hot and 240 uses both hots.

Probably want to confirm if battery charger is 120 or 240 as they are usually not interchangable, although some can be set for either.

[Moontide]

P.S. Most that i have seen on cruising boats is 50 amp 240 and in marinas (including in Mexico) for boats under 70' or so. My shore cord is about 1 inch thick. If you have a smaller cord it is probably a 120 cord (don't think I've every seen a 30 amp 240 cord).
Bill