Shorepower Charger and Combiner

[macbeth]

I have a "Combiner" connecting my House and Starting battery, i.e. if one battery starts getting charged, (alternator or shorepower charger) then so will the other, the amount of current going to each battery dependent upon it's state of charge.

My shorepower charger has TWO output wires, i.e. I could connect a charging (current) wire to each battery. SHOULD I USE THE TWO, OR JUST CONNECT ONE WIRE ? If just one battery, which one ?

Thank you !

[osirissail]

As far as shorepower charging the battery combiner is redundant. However, how is the engine alternator wired? If it is only wired to one battery bank then the combiner is providing a useful function.
- - The shorepower battery charger is normally wired to each battery bank if it does have a "dual" or more output terminals.
- - However, the engine alternator, unless you have a diode splitter, can only be wire to one battery bank.

[redcobra]

Originally Posted by osirissail

As far as shorepower charging the battery combiner is redundant. However, how is the engine alternator wired? If it is only wired to one battery bank then the combiner is providing a useful function.
- - The shorepower battery charger is normally wired to each battery bank if it does have a "dual" or more output terminals.
- - However, the engine alternator, unless you have a diode splitter, can only be wire to one battery bank.

My AC bat charger goes to both battery banks. My alternator (with Balmar smart regulator) goes to the starting bank with a Blue Seas combiner then feeding the house bank.

Has worked great so far.

[macbeth]

Originally Posted by osirissail

As far as shorepower charging the battery combiner is redundant. However, how is the engine alternator wired? .

The alternator output cable comes back to the common terminal of the Battery switch. Which is then connected to whichever battery the switch is pointing at.

However, (while writing this), I'm thinking, since I have a combiner, it might be a better idea to have the alternator coming back to the house battery ? (Then wouldn't have to worry about accidentally moving the switch through OFF and thus blowing the alternator !)

I've noticed a lot of switching noise from the combiner when connecting the two shorebattery wires to the two batteries, so I'm only using one connection, and it seems better.

[doug86]

Originally Posted by macbeth

I have a "Combiner" connecting my House and Starting battery, i.e.

You put "Combiner" in quotes. There are actually three different devices that allow separate battery banks to be connected, and it would help to know exactly which one you have.

-An isolator, which is just a big box with one terminal for input and two terminals for output. Each battery bank gets a charge from a single charging source, but the two banks are isolated by diodes.

-An Echo Charger, which uses the power from one batter bank to produce a charging voltage at another bank. Echo chargers turn themselves off when the charging voltage from the power bank drops below about 13v, so they only work if the power bank is actually getting a charge from yet another source. The Echo charger is a one way device.

- A combiner "is a voltage-sensing relay (13.3 volts) which connects two batteries together when either is receiving a charge. When the charging ceases, the relay opens so that each battery operates independently. " So a combiner will connect the two banks whenever either of those banks is getting a charge; it is a two way device.

[osirissail]

Originally Posted by macbeth

The alternator output cable comes back to the common terminal of the Battery switch. Which is then connected to whichever battery the switch is pointing at.

However, (while writing this), I'm thinking, since I have a combiner, it might be a better idea to have the alternator coming back to the house battery ? (Then wouldn't have to worry about accidentally moving the switch through OFF and thus blowing the alternator !)

I've noticed a lot of switching noise from the combiner when connecting the two shorebattery wires to the two batteries, so I'm only using one connection, and it seems better.

Classically the engine alternator charge line should be connected to the engine starting battery. If you have an external "smart regulator" on the engine alternator then there is a "sensing" wire that should also be attached to the engine starting battery.
- - The idea is that the engine starting battery is dedicated to being able to start the engine and it is not available to be used as a "house bank" battery.
- - Then a battery combiner or echo charger is used to redirect the alternator power to the house batteries after the engine start battery is satisfied.
- - In no way should the engine alternator output be connected through the switching function of the ship's main battery switch unless you have a special battery switch that contains a separate set of terminals that will turn off the engine alternator regulator when the battery switch selector is moved.
- - If you have an "internal" regulated engine alternator (i.e., an automobile type alternator) then there is only one terminal on the back of the alternator and no provision for using a "smart" external regulator. This is where you would connect its output to the "critical" battery which is the engine start battery. And as I said earlier, connecting a dual output charger to each battery bank in conjunction with a battery combiner basically takes the battery combiner out of the circuit and it is not really doing anything useful. However, if your engine alternator does not have a "diode splitter" then the combiner or echo charger is necessary.
- - It is normal for battery combiners to "rattle" when charging is started but they will settle down once the battery voltage exceeds the "trigger" voltage of the battery combiner. This does not hurt the unit.

[doug86]

Originally Posted by osirissail

Classically the engine alternator charge line should be connected to the engine starting battery. If you have an external "smart regulator" on the engine alternator then there is a "sensing" wire that should also be attached to the engine starting battery.

Actually, most modern set ups are exactly the opposite. The alternator charges the house bank, and an echo charger feeds the start battery.

The rationale for this is that the start battery barely needs any charge, and the small amount of amps coming from the echo charger is sufficient to recharge it. The house bank is typically the bank that needs a huge bulk charge, so that bank is attached directly to the alternator output, so that bank can get the full benefit of a 3 stage or smart regulator.

In either case, it is a good idea to keep the start battery separate from the house bank.

[macbeth]

Originally Posted by doug86

You put "Combiner" in quotes. There are actually three different devices that allow separate battery banks to be connected, and it would help to know exactly which one you have.

-An isolator, ...... NO

-An Echo Charger, .......NO

- A combiner "is a voltage-sensing relay (13.3 volts) which connects two batteries together when either is receiving a charge. When the charging ceases, the relay opens so that each battery operates independently. " So a combiner will connect the two banks whenever either of those banks is getting a charge; it is a two way device.........YES

Please see responseS above. i.e. I have a COMBINER. Thanks for replies.

[macbeth]

Originally Posted by doug86

Actually, most modern set ups are exactly the opposite. The alternator charges the house bank, and an echo charger feeds the start battery.

The rationale for this is that the start battery barely needs any charge, and the small amount of amps coming from the echo charger is sufficient to recharge it. The house bank is typically the bank that needs a huge bulk charge, so that bank is attached directly to the alternator output, so that bank can get the full benefit of a 3 stage or smart regulator.

I should have mentioned I do have a smart regulator: HEHR Aqualine from Powerline. Model 10-184. It has three step charging with a 90 second delay before it starts charging, then the alternator output comes up gradually.

I have a Muir 1200 windlass directly connected to the Starting battery, with its own circuit breaker (100amp) and switch

My combiner is an 2001 era West Marine 150, model 128293.

My alternator is a 120 amp Powerline.

I agree I MUST move the alternator output from the battery switch common terminal ! But to House or Starter battery ? There seems to be a conflict in the responses above.

I lean towards connecting the alternator output to the starting battery as the windlass is connected to it directly, and must use a lot of amps as its pulling up the 35lb anchor with 55' chain attached to it, especially after a night of 20 knot wind with the anchor embedded in mud and weed. On the other hand, the house battery is always down about 30 AH per day, due to frig draw. And an 800 watt inverter is connected to the house battery, but the inverter doesn't get much use.

Opinions welcomed !! Thanks very much.

[redcobra]

I use the Blue Sea ACR (Automatic Charging Relay). Here is what their web site says (below). The Alternator is connected to the start battery as to me that is the most important battery. The ACR is connected to both battery banks. The AC (Shore Power)Battery charger can be connected to both batteries but it's not necessary.

What is an ACR? An ACR parallels (combines) batteries during charging, and isolates them when charging has stopped and after battery voltage has fallen. An ACR is intended to keep a load from discharging both of the batteries.

• How does an ACR work? An ACR senses when the voltage of either of the batteries rises to a level indicating that a charge source is active (13.0V for 2 minutes). The ACR′s contacts then connect and the ACR applies the charge to both batteries. If the voltage on both of the batteries subsequently drops to 12.75V for 30 seconds, the ACR will disconnect, isolating the batteries.
• Why do I need an ACR? An ACR allows two battery banks to be connected so that they can share the output of a single charge source, allowing the user to charge more battery banks than the number of charging outputs. For example, an ACR can be used with a single-output charger, resulting in a simpler system at lower cost than a dual-output charger.

[redcobra]

Originally Posted by macbeth

My combiner is an 2001 era West Marine 150, model 128293.

I would get rid of the WM 150 as they are pretty old technology. I have had several fail.
Just my $0.02/

ps: I also use a dual circuit battery switch which isolates the house circuit and the starting circuit, but allows them to be combined in an emergency.
http://bluesea.com/files/resources/i...eb_version.pdf

[Mark Johnson]

I prefer the Blue Sea combiner to get the charge to the engine battery, and I have my alternator, solar array, dockside charger, and at one time... the wind gen, ALL wired to the house bank! I consider IT the most important, as it runs EVERYTHING, costs 10 times more, and can ALSO crank the engine! The engine battery should always be about 98% full after cranking the engine, and if it had an unexpected problem, I can switch the engine "cranking option" three way switch from eng. battery to house battery, to crank the engine. In 15 years I haven't needed to.

I ALSO have a three way switch to run the boat off of the house batteries, (like normal), OR the engine battery.

These switches are simple, fairly inexpensive, and highly reliable. They give me ALL of the options, and routing ALL charge sources to the house bank, with the Blue Sea combiner letting the engine battery get it's due after the line V reaches 13.5, is the best way to go... IMO.

Best of luck,

Mark

[DeepFrz]

Move the connection from the alternator to the house bank. The start battery typically requires very little recharging, although with the windlass connected to the start battery it will require a little more. The house bank is usually the one that needs the most charging time and amps.

[osirissail]

Originally Posted by DeepFrz

Move the connection from the alternator to the house bank. The start battery typically requires very little recharging, although with the windlass connected to the start battery it will require a little more. The house bank is usually the one that needs the most charging time and amps.

Logically and practically, you would connect the alternator output to the battery bank requiring the most recharging - but - from a safety standpoint the starting battery is the most critical battery on the boat. Without the ability to start the engine due to a depleted engine start battery, you could be in deep do-do. Whereas a depleted house bank simply is an inconvenience.
- - The reason I used the word "classically" is that in modern DC systems there is a "crossover" battery switch that will allow you to select the engine starter from either the normal engine start battery - or - the house battery bank. That switch must be wired so that there is no option available to connect the start battery to the house bank batteries.
- - With the option to connect the engine starter to either the engine start battery - or - the house battery bank then the output of the alternator would be most logically connected to the house bank - and - most importantly - the battery sense wire from the external "smart charger" should also be connected to the house battery bank. Then the use of a "combiner" or echo charger would keep the engine battery charged.
- - Where this system breaks down is when you have a failed battery in the house battery bank system such that the alternator output cannot bring the voltage of the house bank up to the "trigger" voltage of the Combiner/echo Charger. Then the engine battery never gets charged and can run down enough to prevent you from starting the engine in an emergency.
- - Connecting any load - windlass or whatever - to the engine start battery is a recipe for disaster. The engine start battery should be kept isolated from any loads other than the engine starter. The reason being safety - should all the other batteries in the boat fail you can at least start the engine and "get out of Dodge."

[macbeth]

Originally Posted by redcobra

ps: I also use a dual circuit battery switch which isolates the house circuit and the starting circuit, but allows them to be combined in an emergency.
http://bluesea.com/files/resources/i...eb_version.pdf

If the starting battery happens to be flat, it seems to me that the combination feature would make the house battery current flow to the starting battery, until you ended up with both batteries at half charge (or worse), before you could push the start button !