Battery Chargers??

[C.Ricko]

We only fit Victron to our hire boats and the private jobs, I removed  Sterling and random stuff from refits before sending them hire... 

[Karizma]

11 hours ago, Oddfellow said:

Probably Battery Charge Splitters (Probably diodes) not combiners.

Common config for 3 banks:
2 banks of 2 will be 2 for the domestic 12v power - 2 for the inverter - 1 for the engine. 

Two alternators. Each should go to to a charge splitter to charge the three banks. 

Hi Andy - 3 x Cyrix Victron Energy 12 volt 100 amp - are they combiners or splitters? 

7 hours ago, annv said:

Hi Karizma Ar now you tell us you have five battery's with two alternators it makes more sense i guess one bank is to run inverter and other bank lights and fridge, have you tried to contact previses owner yet?. John

Hi John, will establish the above once I've traced more of the wiring - though it does give me something to look out for - thanks. Unfortunately the previous owner didn't 'dig' this deep, on the basis that "if it's not broken ......... "

[Oddfellow]

20 minutes ago, Karizma said:

Hi Andy - 3 x Cyrix Victron Energy 12 volt 100 amp - are they combiners or splitters? 

They are combiners. 

The terminology can be confusing. 

A combiner senses the alternator charging and the closes a relay so that charge is sent to the battery(s) that's in the circuit after the relay. 

A splitter is a heavy-duty diode that prevents the batteries from being combined and charging into oneanother but passes the charging current through - it's a one-way-gate. 

Ultimately, both do the same job and there are pros and cons of each system. A diode will introduce a voltage drop which means the batteries aren't charged at the full voltage. The combiner will not do this and is generally considered to be better. There is a very small risk that the relays could fail and combine the batteries when not charging which is bad. It is a VERY small risk though. 

Some systems just use a large relay for the charging and this works too, but is less advantageous than what you have as it doesn't need to sense power from the alternator, just receive enough to close the relay. If the alternator is  dodgy, this could combine the batteries in error and you end up with all your banks being flat.