We recently split our battery bank into 2 separate units mainly for charging purposes.

Our vessel is used 12 months of the year and is rarely on shore power. Amel provided the vessel with 12-12V lead acid house batteries with a Dolphin 100 Amp charger and a 30 Amp Dolphin charger. The 30 Amp charger is used for when connected to shore. Our research indicated that a 100 Amp charger is good for charging a battery bank of up to 400 Amp/Hrs. We currently consume 130 amp/hrs per day

The Dolphin charger was not of sufficient capacity to maintain the battery bank at the levels for charging. As per the Trojan Battery Company's charging and maintenance guide the charging voltage daily during absorption should be between 29.2V – 29.6V.(http://www.trojanbattery.com/pdf/UsersGuide_English.pdf) To accomplish this on the Dolphin, the #2 setting (which gives 29.6V) was selected. Due to line loss, the voltage to the batteries is 29.2V. We confirmed this with the USA representative in Florida. There are no settings available on the Dolphin 30 Amp charger to provide this voltage.

Our current Amp/Hr capacity is 1,290 Amp/Hrs (12 X 215 Amp/Hrs divided by 2) The batteries are type 31 made by UltraPower.

As we saw it the 100Amp charger was not sufficient to do the job hence splitting the batteries into 2 banks to 645 Amp/Hrs in each bank. The 100 Amp Dolphin charger still would not do the job as there are more than 400 Amp/Hrs. We then decided to install another battery charger with inverter capabilities. We chose a Magnum MS-E Series Pure Sine Wave Inverter/ Charger Model # MS4124E. This charger provides 105 Amps of charging power. We note that we get 114 Amps when charging (Bonus) The inverter provides us with 220V 50 Hz power to run the appliances on board without having to start the Genset. Cost of unit with remote control, temperature sensor & shipping $2,066.41 USD.

Now we can charge each bank with sufficient Voltage and Amps and it takes half the time when using both chargers. Other stand alone marine chargers were much more expensive and did not have the inverter function. Magnum chargers are mainly made for the trucking industry and do not carry the marine markup that we often see in place. The Magnum charger is a much smarter unit than the Dolpin in that it allows adjustments and tapers off when charging with Dolphin charger. When the Genset output is done to 14 Amps we turn off the Dolphin and leave the Magnum on as it is smarter and charges the batteries properly after the bulk charge.

As a result of the split we installed a Link 20 monitoring system to check the banks. The old Link 10 monitor now does the 12V starting battery. We also had designed another monitoring system by Blue Sea to monitor the output from the genset which has a 30 Amp breaker. When running both chargers the genset is putting out 29 Amps. As you may be aware a fully loaded and working diesel engine likes to be loaded up and will last longer. When charger is half done then we can turn on other 220V systems. This unit also tells us how the genset is working and when it may need repairs to the electrical part of the genset. It also allows us to monitor the draw from individual units on board and we can fix if we see a drop or increase in what the particular system is drawing.

This project took over 3 years to design and understand the Amel systems with a lot of input from people far more knowledgeable than us.

We now use one battery bank every 24 Hrs and then switch to the other bank ( bank 1 on odd days and bank 2 on even days)


BENEFITS
Less time charging the battery banks saving genset hours, fuel and maintenance
Inverter can supply power to 220V/50Hz systems without genset having to be run
When hooked up to shore power either 110V or 220V 50 or 60 hz the charge is run through the Dolphin 30 Amp charger and we then use the inverter to obtain 220V/50hz for our power needs on board. As a note the Air conditioning units require 50hz contrary to what Amel says. We checked with Clima on this and they stated on numerous occasions from different technicians that the capacitors will blow out. (As a side note when we were on shore power in the US we ran the Air Conditioning units and as a result had to replace 12 of the 15 AC capacitors as they were blown and not functioning) As we normally only have 110V/60hz or 220/60hz available we took this route. The added benefit of the Blue Sea unit is that it tells us what type of power is coming on board either 110/220V & 50/60hz
We can monitor what each unit is drawing on both the 24 V and 220V systems IE: Washer/Dryer, AC units, Bow thruster, Winches, Furlers etc

We now have the capability to know what is going into and out of the batteries. With the batteries being able to rest for 24 Hrs, we feel they will last longer and will not require equalization. We did not keep track of all the costs but installation took approx. 20 hours along with a lot of wire.
Magnum Charger $2,066.41, Link 20 $375.15, Blue Sea Monitor $875, 12 Batteries $1,285.48

As a side note the Dolphin 100Amp charger has an equalization setting. When we asked the Florida technician, he then inquired to France and they stated in no uncertain terms by email to not use it. We are on our 3rd Dolphin charger replaced 2 under warranty and 1 due to water damage when the water maker high pressure hose blew. It appears that the charger is set up for charging 2 separate banks but the divider breaks down over time. This was even before we installed the additional charger. Warranty work is dismal as they had to send units to France then on to the manufacturer. Our last warranty unit took over a year to be returned and we currently have one in for warranty since October 2010 and they don't know when we will get it back. The company is owned by REYA and they have some one else build them in Europe we think but can't confirm who. The USA representative is looking for another source to provide warranty work as REYA's contract expired in December 2010. The Florida representative, Steve, has been more than helpful. His hands are tide and the company has tried on our behalf and numerous others to get info which is not coming back to them. When they ship the units back they go on a pallet as there are so many. No wonder they are looking for a new warranty provider. Who needs this type of customer service.

Paul LaFrance
SV NOMAD SM 362 Currently in St Lucia