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riot138

Noco 2 bank Onboard Question

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riot138

Hello,

I installed the NOCO Genius 12V 2-Bank 20-Amp on board  charger next to my stereo amps.  I would like to leave this plugged in every once in a while to make sure the batteries are fully charged but I am wondering do I have to disconnect the neutral or positive or both from the boat to start charging or can I leave everything the way it is and screw the eyelets on to the top posts and just leave them there and plug the unit in and be done?  I have two batteries and I don't have a perko switch so I am thinking they are wired in parallel?  I tried this out yesterday and about 5 hours later the red light was still on and I got nervous that I may be overcharging them.  The manufacturer recommends unplugging the neutral before charging but I read in the FAQ section you don't have to so I'm not really sure.  It's only a few minutes to undo the tops of the battery box and disconnect the terminals but I'd rather not if I don't have to.

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APoko

If the batteries are wired in full time parallel you should probably only be using a single bank charger.   It sounds like what you have is a single bank consisting of 2 batteries.  A dual bank charger is for when you have 2 batteries on different circuits or two battery banks which are somehow isolated from each other.  If I were you I would probably install a battery switch so you can use one of your batteries as a reserve, or at a minimum use the switch to separate them for storage and charging and only switch it to "combine" when the boat is actually in use (this is better for battery health). Or you can leave it as it is, but only hook up one output from the charger which should effectively charge both batteries. 

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riot138
26 minutes ago, APoko said:

If the batteries are wired in full time parallel you should probably only be using a single bank charger.   It sounds like what you have is a single bank consisting of 2 batteries.  A dual bank charger is for when you have 2 batteries on different circuits or two battery banks which are somehow isolated from each other.  If I were you I would probably install a battery switch so you can use one of your batteries as a reserve, or at a minimum use the switch to separate them for storage and charging and only switch it to "combine" when the boat is actually in use (this is better for battery health). Or you can leave it as it is, but only hook up one output from the charger which should effectively charge both batteries. 

Thank you very much!

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MLA
17 hours ago, riot138 said:

I installed the NOCO Genius 12V 2-Bank 20-Amp on board  charger next to my stereo amps.  I would like to leave this plugged in every once in a while to make sure the batteries are fully charged but I am wondering do I have to disconnect the neutral or positive or both from the boat to start charging

No. Outside of a failure, that charger will not produce voltage high enough to damage any electronics

Its also ok to use that 2-bank charger to charge 2 12V batteries in parallel, IF thats how those batteries exist normally. You will get the chargers 20A output potential between the 2 bank leads. 

With that said, im a huge fan of having some form of ON/OFF switch in order to power down the boat when not in use. Without, you might have some parasitic draws that will bring the battery down over a layup. If a charger is used, that draw might keep the charger out of idle/float mode. This has the charger working all the time and can eventually over charger the battery(s).

I would consider taking it a step further, and install a dual-bank switch.  

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riot138
7 hours ago, MLA said:

No. Outside of a failure, that charger will not produce voltage high enough to damage any electronics

Its also ok to use that 2-bank charger to charge 2 12V batteries in parallel, IF thats how those batteries exist normally. You will get the chargers 20A output potential between the 2 bank leads. 

With that said, im a huge fan of having some form of ON/OFF switch in order to power down the boat when not in use. Without, you might have some parasitic draws that will bring the battery down over a layup. If a charger is used, that draw might keep the charger out of idle/float mode. This has the charger working all the time and can eventually over charger the battery(s).

I would consider taking it a step further, and install a dual-bank switch.  

Thank you.  Adding the switch is now on my to do list!

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riot138

Update.  I took all the cables off and fully charged both batteries.  Then I let the boat sit for a day with everything hooked up and I plugged the charger back in and within 5 minutes the green light indicating battery 1 was fully charged came on and within 10 minutes the green light came on for the 2nd battery.  So I am pretty sure you can leave everything plugged in and the noco will isolate the 2 batteries and charge them independently.

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MLA
53 minutes ago, riot138 said:

and the noco will isolate the 2 batteries 

The charger cannot do this. Isolation has to be done by either a dual bank switch being turned off or the house bank completely a stand-alone bank. If the batteries are wired in parallel, they are one battery. 

The charger can and does, charge them independently, IF they are isolated by a switch or siring. 

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riot138
Posted (edited)

i

29 minutes ago, MLA said:

The charger cannot do this. Isolation has to be done by either a dual bank switch being turned off or the house bank completely a stand-alone bank. If the batteries are wired in parallel, they are one battery. 

The charger can and does, charge them independently, IF they are isolated by a switch or siring. 

I wonder how it would realize that the one was fully charged and stop and then later realize that the 2nd battery was fully charged and stop.  They were both red (charging) and then at different times green (charged)? I don't know enough about this but I am wondering if the loop would be closed by the ignition being off?

Edited by riot138

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MLA

The charger will attempt to evaluate, charge and condition each bank individually, as its designed. But with 2 or more batteries wired together, they will act as one battery. If he batteries are different age, size, types, brands or had been used differently, they will have different internal resistance. This will effect the other battery tied to it, and how it charges and discharges.  

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