Replacing 12v with 6v batteries

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KAL

KAL

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I currently have 2x12v 110ah leisure batteries wired in parallel, and it may now be time to replace them. Could I use 2x6v Trojan T105 225ah wired in series to achieve roughly the same configuration?

I suppose this would mean reconfiguring the wiring from the present sterling charger, solar/Wind regulator and shore power as well.

Any advice gratefully received.:)
 
Yes, just wire the 6v batteries in series and then treat them as a single 12v battery.

They're all just boxes of 2v cells - the 12v batteries have six in the box connected in series, the 6v batteries have three. Whether the cells are all in the same box or in two adjacent boxes doesn't make much difference.

Pete
 
Assuming that with your present set up you have one positive and one negative wire going to the battery bank you should not have to alter any charger wiring.
two six volt 225ah batteries wired in series will appear as one 12 volt 225ah battrey.
Drat! beaten to it!
 
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Thanks both. Do you reckon changing to the Trojan 6v idea would be an improvement on the present arrangement then? (i.e. more bang for buck in terms of capacity)?
 
KAL said:
Do you reckon changing to the Trojan 6v idea would be an improvement on the present arrangement then? (i.e. more bang for buck in terms of capacity)?
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As I recall, T105s are rather more expensive than leisure batteries, although they could last longer perhaps. But changing from your existing 220Ah to your proposed 225Ah capacity isn't going to make any significant difference.
 
do you have a separate starter battery?

If you're going to go the 6v route, you'll need one because if you get a battery failure you won't be able to start the engine.

If you do have a starter battery, go for the Trojans, they work very well.
 
pvb said:
As I recall, T105s are rather more expensive than leisure batteries.
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I daresay the OP has a supplier in mind, but without much shopping around I found them at £117 each, delivered. You're right, of course, that they'll give no significant extra Ah per buck (except in as much as they can safely be cycled more deeply). But with the same level of maintenance and care, they should last longer.

I might add that you also know exactly what you're getting: in many instances 'leisure' as a battery description is virtually meaningless.
 
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macd said:
But isn't that the case if he has Trojans or anything else? A dead 12V is just as dead as a dead 6V.
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I think he is suggesting that the Trojans don't have a high enough CCA to start an engine. Some commentators suggest that they do, in most instances.

Having said that, not having a separate starter battery in any installation risks the domestic appliances flattening the multi purpose bank, in which case you wouldn't be able to start the engine without a separate starter battery.

If space allows, I'd suggest a separate starter is a must.
 
Richard10002 said:
I think he is suggesting that the Trojans don't have a high enough CCA to start an engine. Some commentators suggest that they do, in most instances.

Having said that, not having a separate starter battery in any installation risks the domestic appliances flattening the multi purpose bank, in which case you wouldn't be able to start the engine without a separate starter battery.

If space allows, I'd suggest a separate starter is a must.
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Quite agree about the desirability of a dedicated starter battery, just couldn't fathom the logic Bobc was employing. Incidentally, amongst the 'commentators' suggesting Trojans are fine for starting are Trojan themselves. Check out their Q&A section.
 
Richard10002 said:
I think he is suggesting that the Trojans don't have a high enough CCA to start an engine. Some commentators suggest that they do, in most instances.

Having said that, not having a separate starter battery in any installation risks the domestic appliances flattening the multi purpose bank, in which case you wouldn't be able to start the engine without a separate starter battery.

If space allows, I'd suggest a separate starter is a must.
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I hope there'll be general relief all round when I say that I do have a separate starter battery!
 
macd said:
Quite agree about the desirability of a dedicated starter battery, just couldn't fathom the logic Bobc was employing. Incidentally, amongst the 'commentators' suggesting Trojans are fine for starting are Trojan themselves. Check out their Q&A section.
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What I was suggesting is that if you have 2 x 12v batteries, if one dies, you still have a 12v battery to start the engine with. However with just a pair of 6v batteries, if you lose one, you only have a 6v source left, so won't be able to start the motor.

If you have a bank of 4 or 6 trojans, the potential problem goes away.
 
Bobc said:
What I was suggesting is that if you have 2 x 12v batteries, if one dies, you still have a 12v battery to start the engine with. However with just a pair of 6v batteries, if you lose one, you only have a 6v source left, so won't be able to start the motor.

If you have a bank of 4 or 6 trojans, the potential problem goes away.
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i think you have missed the bit about 2x 6v in series making a 12v bank?
 
Bobc said:
What I was suggesting is that if you have 2 x 12v batteries, if one dies, you still have a 12v battery to start the engine with. However with just a pair of 6v batteries, if you lose one, you only have a 6v source left, so won't be able to start the motor.

If you have a bank of 4 or 6 trojans, the potential problem goes away.
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Right Bob, now I understand, makes perfect sense. Of course that only works anyway if you notice the death before it pulls the other one down.
 
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