Help.Do I need a second perko switch?-gctid385656

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[img]/media/kunena/attachments/vb/689189=28125-31620_L1.jpg[/img] I cant find any diagrams on how to wire two sepatate house banks and a starter battery to this switch.Do I need another switch or is there another way I can do this.There is a neg and pos bus at the helm on this boat.Can I leave the starter batt off this switch?

[JimMc Guru Find all posts View Profile Close JimMc]

Well you have choices. But in short you can not have two house banks and a starting battery all off of that switch.

You can put both House Banks on this switch and add an On/Off switch for the starting battery.

You could install a second switch for selecting between House Banks.

But my real question is why have seperate House Banks ?

Create one House Bank assuming the batteries are the same chemistry. Then use the switch you have for selecting between the Starting Battery or House Bank.

[2850Bounty Supporting Member Find all posts View Profile Close 2850Bounty]

JimMc wrote:
Well you have choices. But in short you can not have two house banks and a starting battery all off of that switch.

You can put both House Banks on this switch and add an On/Off switch for the starting battery.

You could install a second switch for selecting between House Banks.

But my real question is why have seperate House Banks ?

Create one House Bank assuming the batteries are the same chemistry. Then use the switch you have for selecting between the Starting Battery or House Bank.

Ditto Jim on all accounts.... in particular, why two separate House Banks?

Your chances of remaining above a 50% SOC (state of charge) are much greater with one large bank, than with two smaller banks.

Add a tad bit of mis-management, and the risk of going below 50% is even greater.

Remember, taking our batteries down below the recommended SOC, and leaving them for any length of time, is what eventually shortens their life span.

.

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Rick,

Reminds me of my earlier posts when I had 3 banks. It was great advise only having one large house bank.

[2850Bounty Supporting Member Find all posts View Profile Close 2850Bounty]

Glen, I had forgotten that until just now.

Did you end up making one bank instead of two?

.

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Will this configuation work as one bank?I have two 12v paired and two 6v batterys paired. I would like to have only one bank if I can.Will my xantrex 20amp charge a large bank like this? not read the manual yet.

Do these chargers measure cuurant loss? would I still need a shunt for that?

Ground the bank to the block correct? Comm wire to starter?

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Prairie Puffin wrote:

• 1 wrote:
• Will this configuation work as one bank?I have two 12v paired and two 6v batterys paired. I would like to have only one bank if I can.
• Will my xantrex 20amp charge a large bank like this? not read the manual yet.
• Do these chargers measure cuurant loss? would I still need a shunt for that?
• Ground the bank to the block correct? Comm wire to starter?

• 1 wrote:
• Not the best scenario to mix the unlike batteries.
• Yes, but again, not the best scenario with unlike batteries.
• The charger accounts for current loss, and predicates it's charge rate accordingly.
  
  A shunt will be part of an Amp Hour battery monitoring system.
• Yes, bank Negative to system negative common....... "common" cable of MBSS to engine starter motor.

Take your two charge leads to the rear of the MBSS #1 and #2 terminals.

Take the charger Negative(s) to the system negative common..... (i.e., engine block)

.

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Right on! Thank you Rick.

[2850Bounty Supporting Member Find all posts View Profile Close 2850Bounty]

See if these help you any.

Where this shows 2 6 volt golf cart batteries, you could use either of your like batteries.

If you want more Amp Hours, the 6 volts (2 paired and in series, then 2 pairs in parellel..... total of 4 batteries), would be good.

Attached files [img]/media/kunena/attachments/vb/689328=28146-Alarm with MBSS Single engine w float switch.jpg[/img] [img]/media/kunena/attachments/vb/689328=28144-MBSS showing terminals 2.jpg[/img]

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I will see about getting another set of 6v batterys thats the way to go I would amagine there will be more strain on one of the sets of batterys I have being mismatched.Thanks for the diagrams will use em.

[2850Bounty Supporting Member Find all posts View Profile Close 2850Bounty]

I should have said:

If you want more Amp Hours, new "like" 6 volts (2 paired and in series, then 2 pairs in parellel..... total of 4 batteries), would be good.

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Prairie Puffin wrote:
I have two 12v paired and two 6v batterys paired.

That set up will work fine so long as all 4 of the batteries involved are of the same chemisrty, i.e. lead acid. Just because one set is 6v and the other is 12v, so long as they are all wired together to be equal (12v) then they will draw down and charge equally. Now, what Rick said about age also comes into play for the longevity of all the batteries concerned. Not wanting to spend money or as little as possible, your above scenario will work fine (the 2 6v batt's in series to = 12v, in parallel with 12v batt #1, in parallel with 12v batt #2). It works like this: say your 6v batt's are 200AH each and the 2 12v batt's are 100AH each, your 6v batt's in series equals 12v but only 200AH total, in parallel w both of the 12v batt's gives your house batt bank a total of 300AH in this case...200+100+100.

Ideally, as Rick mentioned, you would want to choose a path... all new 6v batteries in a series parallel configuration or all new 12v batteries in a parallel configuration. Same brand, chemistry and age is the ideal way to go. The expense sometimes limits your options.

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2850Bounty wrote:
Glen, I had forgotten that until just now.

Did you end up making one bank instead of two?

.

Yes, when I added the Xantrex Inverter/Charger. Our UPS configuration in the Data Center is always in sets of 3, so that's why I had my head with that in mind. It's to allow redundancy at all times, even when a bank is being serviced.

I combined 4 x 120Ah batteries as one bank. Never goes below 50% now with 4 days on the hook.

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Did I do this correctly? should I have the 6v battery positive go to the perko switch or does it matter.

Attached files [img]/media/kunena/attachments/vb/690078=28241-batterys.JPG[/img]

[2850Bounty Supporting Member Find all posts View Profile Close 2850Bounty]

I should leave this to the more knowledgeable battery guys!

But right off the bat the only issue I see with this, is bringing two 6 volt "in-series" batteries in with two 12 volt "paralleled" batteries.

The two paralleled 12 volt batteries offer 12 volts, and the two "in-series" 6 volt batteries also offer 12 volts.

I suppose that you could look at this as though you have three 12 volt batteries being paralleled.

However, while the chemistry may be the same, the capacity is not.

Will it work? Yes.... but how effectively?

I'll give you option 1 as the green connection...., or option 2 as the blue connection.

One or the other should work OK.

Attached files [img]/media/kunena/attachments/vb/690086=28242-Prairie Puffin HLBB .jpg[/img]