Replacement for 1-2-both switch

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Has anyone seen anything on the market that can replace the 1-2-both switch but is designed for an isolated setup. I'm going to fit a diode but rather than get 2 new isolation switches, and an emergency parallel, it would be great if I could get something that fit in place of the old 1-2-both switch which was more like a on-off-parallel switch.
 

RobBrown

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I replaced my 1,2,B switch with one of these, alongside the installation of a 0 loss diode splitter:

http://bluesea.com/products/5511e

Works very well indeed. Especially like not having to think/remember whether I am on bat 1 or 2 & whether to switch to save/charge the other. Also the "emergency" paralleling is very handy on a cold morning with a reluctant Bukh!
 

Stu Jackson

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WADR, not really. That switch combines banks when one is dead. Not a good idea.

The simplest and least expensive way to do it is to KEEP your 1-2-B switch. Simply remove the alternator output from the C post of the switch and run it to your house bank. Either get an ACR or just use B to charge both banks.

Think of it this way: instead of a charging "decider" the switch becomes a "use" switch. No way to blow alternator diodes when connected to the house bank.
 

VicS

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Either get an ACR or just use B to charge both banks.
For ACR read VSR :)

The trouble with diode splitters is the volts drop. You either have to use some no loss device as suggested by RobBrown or convert the alternator to battery sensing.

A VSR ( ACR) does not suffer from volts drop
 
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William_H

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1,2,both switch

I would suggest you keep the switch. Just rewire and relabel the switch so that it switches just engine battery supply. So "1" becomes normal engine battery to engine. '2' becomes house battery to engine for starting (used only in the case of engine battery being totally dead) and both being for engine battery boost. (more likely emergency engine start function.)
Move all the house battery supply switching to another switch which can be a lot smaller needing only to carry charge current and service current. Fit the VSR or 0 loss diode to supply charge current to both batteries. good luck olewill
 

VicS

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A down side of the BEP cluster is that wired as shown in the Installation and Operating Instructions download is that the emergency paralleling switch links the two batteries directly. You would not want to do this if one battery is defective as it may then discharge the good battery.

It would be better if the panel was configured so that the engine and domestic circuits, rather than batteries, were linked by the emergency paralleling switch. That way a defective battery could be isolated and all functions run from the good battery.
 

pvb

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A down side of the BEP cluster is that wired as shown in the Installation and Operating Instructions download is that the emergency paralleling switch links the two batteries directly. You would not want to do this if one battery is defective as it may then discharge the good battery.

It would be better if the panel was configured so that the engine and domestic circuits, rather than batteries, were linked by the emergency paralleling switch. That way a defective battery could be isolated and all functions run from the good battery.

I agree, Vic, but it would be easy to remove the jumper link and wire a new link in.
 

VicS

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I agree, Vic, but it would be easy to remove the jumper link and wire a new link in.

Yes . I meant to say "It would be better if the panel was re-configured ...."

Leaving the links and swapping the other wiring between A and B and between C and D would do the trick I think
 
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I'm not a big fan of VSRs, and have a smart alternator regulator so the voltage drop from diodes is not an issue. That switch would be even better though if instead of a parallel it just diverted the house bank to the starter motor, then it would avoid any issue of a dud starter battery draining the house bank in parallel mode - and prevent idiots from using their engine start battery to run domestic stuff :)
 

VicS

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That switch would be even better though if instead of a parallel it just diverted the house bank to the starter motor
I think that boils down to pretty much what WilliamH was suggesting although he retained the original switch with its parallel connecting capability
 

ithet

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But another vote for the original suggested Blue Seas 5511e, does exactly what the OP wanted. Very simple fool proof solution for normal use situation. Crew has only to turn one switch through one position - simples.
 

VicS

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But another vote for the original suggested Blue Seas 5511e, does exactly what the OP wanted. Very simple fool proof solution for normal use situation. Crew has only to turn one switch through one position - simples.

But Like the BEP cluster it links the two batteries in parallel mode. You cannot isolate ( without physically disconnecting) a defective battery and use the good battery only for all functions.
 

ithet

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But Like the BEP cluster it links the two batteries in parallel mode. You cannot isolate ( without physically disconnecting) a defective battery and use the good battery only for all functions.

Yes agreed, but having to physically disconnect is a small price to pay for a huge increase in simplicity. If it ever comes to matter and the skipper thinks "oh I have a defective battery I must isolate it" he can go disconnect the positive terminal (it is going to need to be taken out sometime anyway). Why live with a complicated set up which can cause operator error just to cater for the eventuality of a rare event?

I am much happier knowing that anyone on board can set the switch correctly on or off. Try this experiment, print out the pictures from the links for the Blue Seas switch and the BEP cluster. Then ask someone unfamiliar with either how to correctly set them on for normal operation. The Blue Seas switch is totally obvious.
 
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