battery isolator replacement suggestions

I would like to replace my old style isolator, which I believe consumes about .6 amps, with an automatic charging relay offered by Blue Seas(7610) or BEP(710125A) for my single alternator (70 amp) 3 battery bank system. Any suggestions? Do I need to keep the generator battery in the system?

Isolators are doomed to failure, so good choice in wanting a different system. You might check out using an echo charger instead of the charging relay. Balmar calls their unit 'Duo Charger'

Although I think that the Balmar Duo Charge is a great product, its benefits over something cheaper like Xantrex's Echo Charger are mostly lost if you don't have an external three step regulator on your alternator.

The Duo Charge has internal logic that produces a separate voltage output for the starting battery, different (and usually lower) from what the alternator is producing for the house bank. But if the alternator is a simple fixed voltage output type- typically 13.5-14.0 volts then there really is no benefit.

Both the Duo Charge and the Echo Charge require that the alternator output be connected to the house bank of batteries and not tied to the starter lug as in most production boats wiring schemes.

So the Blue Seas device or something similar like the Yandina battery combiner is probably the best solution in this case.

David

I recently installed a Blue Sea Add A Battery kit to manage the charging of my two battery banks. This kit includes a 7610 ACR and a 5511a Switch that allows you to manually combine the banks. I think you would need to add a second 7610 ACR to maintain a third bank. Here is a link to the Add A Battery kit.
Blue Sea Add-A-Battery Kit 7650
So far I'm pretty happy with the system but it's only been on my boat for a few months.

Bensjoy said:

...Do I need to keep the generator battery in the system?

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Our generator's battery is off by itself. If something fails in the other battery systems, we can always start the generator for AC power or we can charge batteries if needed.

Larry M said:

Our generator's battery is off by itself. If something fails in the other battery systems, we can always start the generator for AC power or we can charge batteries if needed.

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What charges the generator battery?

Rambler said:

What charges the generator battery?

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The generator.

just trying to follow the logic here, because if my car battery starts the car engine, and the car battery is charged by the car engine, if (or when) the car battery dies, how does it get charged if it can't start the engine?

I guess you carry jumper cables?

Rambler said:

just trying to follow the logic here, because if my car battery starts the car engine, and the car battery is charged by the car engine, if (or when) the car battery dies, how does it get charged if it can't start the engine?

I guess you carry jumper cables?

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Jumper cables will work. You only need one, all the negative terminals are already connected together.

Unlike a car where the single battery provides all the electrical power used, the starting battery on a boat with an additional house bank provides power only when starting the engine (and a very small amount for the instruments). If it "dies", it is probably really dead and cannot be charged.

Larry M said:

The generator.

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Or a small solar panel, charging via a simple regulator. Battery stays full,lives longer,for less than the cost of the battery. BruceK

RV solenoid $18.00,, power off the ACC position on the engine key switch.

Seamless , no thought almost no expense , and no voltage drop like expensive transistor gadgets.

Rambler said:

just trying to follow the logic here, because if my car battery starts the car engine, and the car battery is charged by the car engine, if (or when) the car battery dies, how does it get charged if it can't start the engine?

I guess you carry jumper cables?

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Hobo has 3 independent systems with no interconnecting switches or cables other than individual disconnects. Each system (house, engine and generator) has it's own alternator and voltage regulator. The engine and generator battery(s), same as your car, is there only to start the engine and run the engine gages. If the starting batteries should die, I have a cable already made up to interconnect the house and engine bank. It's a simple system and there hasn't been an issue in 13,000+ miles.

The generator's battery is an Optima Blue Top, the engine has 3-Optima Red Tops and the house bank is made up of 10-Trojan T-105's.

Bensjoy said:

I would like to replace my old style isolator, which I believe consumes about .6 amps,

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The isolator doesn't consume any current (amps) or power (watts), but an isolator does have a voltage drop of about.6 volts across the diodes which prevents fully charging any of the batteries. Replacing it with a battery combiner is a good idea.

Blue Seas Systens, BEP, and Yandina are some of the better known brands. These are more than just a relay, they have circuits to combine the batteries when a charging voltage is present, seperate them when it is not, and allow the starting battery to regain it's charge before beginning to charge the house battery.

Isolators

I have four batts, and two Yandina 100's (1 for 2 batts) works for me.
My 5th batt is only for the genny and that charges it's own batt.

Bensjoy: we're guessing that your 3 batteries are (propulsion engine) Start; House; & Genset Start...is that correct and do you have different battery technologies (eg: 6-volt flooded acid for House; Optima spiral-wound for Start)? I like Balmar's DuoCharger as it has the smarts to cope with different battery technologies, which I think is a good thing. It is not expensive; I'd stay away from anything Xantrex....plenty of quality problems reported on this site and others. BEP products are also very high quality

HopCar said:

I recently installed a Blue Sea Add A Battery kit to manage the charging of my two battery banks. This kit includes a 7610 ACR and a 5511a Switch that allows you to manually combine the banks. I think you would need to add a second 7610 ACR to maintain a third bank. Here is a link to the Add A Battery kit.
Blue Sea Add-A-Battery Kit 7650
So far I'm pretty happy with the system but it's only been on my boat for a few months.

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This system did NOT work for me. The relay for charging the house bank would not stay engaged.
After a very long session on the phone with Blue Seas, the tech said everything was working liike it should..however my house bank was too large (4 6v) and when the relay engaged the voltage would drop too much and the relay would open.
Said there was nothing I could do to change that other than making the battery banks closer to equal in capacity.
So I have cruised all summer with all batteries as one big bank. So far that has worked out super. (And I have not had to add water to any battery all summer)

You could ask the expert in battery isolator or read the article about it here: How To Install Battery Isolator For Your Car Audio

Thanks for everyone's input regarding my battery isolator question. I plan to use the BEP or Xantrex combiner and keep my generator start battery isolated. My batteries are all flooded acid type. My starting battery is a 4D and my house bank consists of 4 - 6 volt "golf cart" batteries . My alternator has an output of 70 amps.

lancemayer said:

You could ask the expert in battery isolator or read the article about it here: How To Install Battery Isolator For Your Car Audio

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Firts of all, welre talking about a boat, not a car. Second, since this is your first post on this forum and the link takes us to a site that sells these things, I suspect this post is more on the order of spam than an honest effort to help boaters.

My alternator has an output of 70 amps.

IF you increase the house bank, the alt may need an upgrade.

As it is you might prefer a 3 stage regulator if your daily engine runs are short.

And a SOC meter (state of charge , under $200)to know where you are with the battset,

rwidman said:

The isolator doesn't consume any current (amps) or power (watts), but an isolator does have a voltage drop of about.6 volts across the diodes which prevents fully charging any of the batteries. Replacing it with a battery combiner is a good idea.

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The problem can be over come with a Smart Regulator such as the Balmar ARS-5 or the MC-612. They have a sensor that goes to the B+ of the house and thus they will adjust the Alt voltage to what ever it needs to be to overcome the isolator diode and line drop. So if you have an isolator off of the Alt that splits the house and the start you can remove the isolator and go directly to the house B+ out of the regulator and then use an Echo charge to handle the start battery. If as in my case the Alt goes to an isolator that splits to the 1-Both-2 selector and the Windlass / Bow Thruster 8D. The sensor and the charge wire that go to the selector can now go directly to the house and an Echo Charger to the start battery. The 8D Windlass/Bow Thruster will get the same voltage as the house by way of the up stream isolator.