dual purpose engine start/domestic batteries

Portofino said:
Mike revisit post #17

Threes a switch to the R of the 13.6 V dial. It says "services " above and "engines" below .
Assuming this the switch and it's on Services
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No you're wrong. That is a switch to determine whether the battery voltage indicator is displaying the voltage for the Services or Engine Start batteries
 
Yes I know that ,but he says it drops to 13.2 off and 13.6 on
So if flicked to engines -he would know
1- the standing V -I think he said 7 -really needs to be over 12.6 V according to AA man to start a car realiably ?
2- When charger ,also which charger is on -some idea of its putting something in .ie should rise .Not sure to 13.6 with knacked batts ,but at least he knows which charger and if it's connected .
I did ask him in another post .

Of course he can,t tell how many Ah are going in typically "bulk " 30-40 quickly dropping to float - but can see float on the charger case LED,s -indeed what they are up to ie Bulk
 
Ok. So as you might imagine the original charger did not last 22 years.
I don't know when the new chargers were fitted but they are 'smart' chargers rather than a standard charger from quick which was oe equipment.

How do I know the batteries are being charged? Because my 12v fridges etc still work and when I turn the chargers off the voltage drops.

Mike is right - toggle switch is to show V across engine or service. And this does show two different values when one is isolated. Thing is in the engine space I have two banks of 6 batteries (manual says Ferretti set it up with 2 banks of three then one bank of six). And the starter motors are connected to two batteries in the bank of six, but all those six batteries are linked together. So I don't see how I can have start and domestic banks - or more over how you can isolate start batteries when they sit in the middle of a bank of link batteries.

As I say - I do t really understand 12v systems that well, other than basic circuitry. I can cope with a start circuit but all the interlinking and crossing for start etc means my port bank has wires disappearing everywhere.
 
Portofino said:
So if flicked to engines -he would know
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He would know what? The engine start batteries will usually always show a higher voltage because there's no drain on them except when starting the engines whereas the service batteries invariably have something draining them. I have had this switch on all 3 Ferrettis I've owned. If you see the battery voltage dropping on shorepower it still doesn't really tell you whether the batteries are knackered or the chargers are not working and as I say I would still want to understand why the charger control display is not showing a reading
 
Deleted User said:
He would know what? The engine start batteries will usually always show a higher voltage because there's no drain on them except when starting the engines whereas the service batteries invariably have something draining them. I have had this switch on all 3 Ferrettis I've owned. If you see the battery voltage dropping on shorepower it still doesn't really tell you whether the batteries are knackered or the chargers are not working and as I say I would still want to understand why the charger control display is not showing a reading
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He's not got a Ah guage that works -which is the best way to tell the chargers are doing there job (s) -assuming it too can be switched between them .
So all we have is the V -which we know works cos it goes up to 13.6 with chargers on and drops to 13.2 when off .
Wether the batts hold the charge is another matter .Of course a load would drop it .
The V presumably the switch works ,cos the pic I think and from the symptoms suggest it on "Service "

Nice to see it on "engine " and see the diff between charger on and off ,also poss work out which charger does what by selectively turning the two C on /off and looking at V guage for Service / engine

Post 63 two bats for starter -i,am listening to Alf re DD and 24 V starter motors -would not be surprised !
As in my post 17 from the pic,s there are 4 x13.6 outlets
12 bats suggests they are arranged on 4 groups ( Not neccassary of equal ie not 3x4 )
Service ,Geny , motor P ,motor Stb
Or in the pic it's not clear but perhaps the lower charger only has 1 outlet ? Can,t really see -if so
Then 3 groups Geny , Service ,both Motors ?

My boat is simple and easy to understand
Port Engine 2x 180 ah linked for 24 V Leads to both starter motors
Stb Service. 2x 180 ah. Linked for 24 V ( everything is 24 v bulbs etc )
A"Parallel " switch on the helm
One 80 ah so called smart charger two out lets one for each bank .And two microprocessors running each outlet independently , so,s not to fry one bank while t,other is getting a big top up .

[ Geny - has its own little 45 ah bat + a small charger dedicated to it ---]

As I said need to google DD starter motors -I,am guessing they are 24 V -hence two connected up ,but maybe a pair for each side -dunno and the rest service + one Geny @ 12 V all arranged in 2xrows of 6 --- dunno .
With two chargers -
 
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I don't know when the new chargers were fitted but they are 'smart' chargers rather than a standard charger from quick which was oe equipment.
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Entirely FWIW I fitted an additional smart charger/invertor to my previous Ferretti but kept the original charger available. Whichever charger was selected I still saw a reading on the charger control display so I don't understand why you are not but then I'm no expert either

How do I know the batteries are being charged? Because my 12v fridges etc still work and when I turn the chargers off the voltage drops.
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On both engine and service batteries?


As I say - I do t really understand 12v systems that well, other than basic circuitry. I can cope with a start circuit but all the interlinking and crossing for start etc means my port bank has wires disappearing everywhere.
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Have you got separate battery isolation switches for engine and services batteries and do they operate as expected ie engine start doesn't work if engine battery isolation switch off and services don't work if services battery isolation switch off?

Just as an aside if somebody has been buggering about with the battery and charger circuits it would be wise to check that all the bilge pumps operate with all isolation switches off because those should be permanently live for obvious reasons
 
Hi mike:

Yep, three isolation switches in the cockpit.
Turn services off and all 12v lights etc go off
Turn engine off and whines won't start. Just click once.

Third is the link breaker to join all batteries. Currently this has to be on to start either engine.

Interestingly if the 12v break is off but the battery charger is on and there is 240v power then the 12v services (lights etc) work as the chargers have a 'power supply' function. If I turn the charger off (or I lose shore power) then the 12v services go off. Seems a good way of leaving 12v grudges running but not risking the drain in the event of a shore power failure.

Bilge pump float switches are permanently live except for was bilge which is knackered - I have new one to replace it.
 
Hi mike:

Yep, three isolation switches in the cockpit.
Turn services off and all 12v lights etc go off
Turn engine off and whines won't start. Just click once.

Third is the link breaker to join all batteries. Currently this has to be on to start either engine.

Interestingly if the 12v break is off but the battery charger is on and there is 240v power then the 12v services (lights etc) work as the chargers have a 'power supply' function. If I turn the charger off (or I lose shore power) then the 12v services go off. Seems a good way of leaving 12v grudges running but not risking the drain in the event of a shore power failure.

Bilge pump float switches are permanently live except for was bilge which is knackered - I have new one to replace it.
 
If you turn "services " bats off and leave "engines " on - can you start engines .?
If so which engine clicks -both or one ?-that's the starter solinoid -but not enough juice for the st motor to turn /overcome the compression .
And have you tried the Oppersite engines off and service on - then attempt to start ?
Tells you if a starter bat is hidden in the service side ? And if there are two sets or one ?
I think DD use 24 V ----- my 24 V system guage for engine shows 27-28 V
So double your 12.8 --25.6. Prob not enough ---- I,am no expert -just observations
 
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Whitelighter said:
Yep, three isolation switches in the cockpit.
Turn services off and all 12v lights etc go off
Turn engine off and whines won't start. Just click once.

Third is the link breaker to join all batteries. Currently this has to be on to start either engine.
Click to expand...
Similar set up to mine then. That tends to suggest then that the engine and services battery circuits are separated as Ferretti originally installed them. It sounds like you also have a similar battery set up to mine in that the services and engine batteries are grouped together and actually its difficult to tell which one is which but they are definitely separated unless you link them together for engine starting. Does look like then you have knackered batteries. No harm in replacing all of them which will be one less thing to worry about for the next few seasons. The charging A not showing up on the charger control display is still a mystery though
 
Bearing in mind the original set up used 1 battery charger, and I know have two, and since there is no way of selecting the charger on the charger control panel - is it possible that rather than connecting 1 of 2 chargers they chose to connect neither?

If that is the case I guess I could trace the install and fit a toggle switch allowing both to be selected
 
Deleted User said:
actually its difficult to tell which one is which
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'scuse me folks if I'm missing something, but I am at a loss in understanding the difficulties in tracing who's who.

First of all, checking which batteries are connected in series or parallel (and as I understand, Jez has a 100% 12V system, so assuming he doesn't have 6V batteries each bank can only have batteries connected in parallel) is just a matter of looking at the connecting cables.

And ref. understanding what each charger does, isn't it just a matter of attaching a tester to each battery bank, turn on/off the charger switches, and see what happens? :confused:
 
MapisM said:
'scuse me folks if I'm missing something, but I am at a loss in understanding the difficulties in tracing who's who.
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What I meant was that at least on my boat I couldn't actually tell you which batteries are the engine batteries and which are the services batteries because they're all in a row, at least without looking at the manual!

And ref. understanding what each charger does, isn't it just a matter of attaching a tester to each battery bank, turn on/off the charger switches, and see what happens?
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Yup I guess so
 
Whitelighter said:
Tested my starboard bank this morning with a meter.

Barely 7v across each battery. I guess regardless of any other issues those 6 batteries are knackered.
Port bank showing 12.8v on their own and 13.6v when under charge, so I think those are ok,

I'm inclined to order 6 of the Numax 110ah 1000cca batteries I linked to. £63 each plus £95 3 day delivery to the marina seems like a deal to me.

Just in the lagoon so if anyone thinks I'm making a horrible mistake shout loudly sometime in the next hour ;)
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I use numax cvx31 110ah 1000cca and I've given them abuse and they do well
 
Deleted User said:
The charging A not showing up on the charger control display is still a mystery though
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It might have been possible that:
the orriginal charger had 2 outputs, (or via diodes) so that both banks were topped up simultaniously
and the charge display was connected straight with that orriginal charger, or was part of it
that could be the explanation why the charge display doesn't work anymore.

now task is to find the exact type number and manual or specs of the current chargers,
and look if they have some intelligence,
= different charge curve at different stages of charging, I believe they are, ..written somewhere above
in that case Jez can keep these.
If not he might put a Victron or Mastervolt charger / invertor on the whish list

there is no display of the charge current, but the voltage display gives a indication if the charger is working or not (as has been mentioned above)
if the charger has intelligence, he should not worry about the charge current,

adding a Victron BMV700 battery monitor , (at leats in the domestic cirquit) gives a lot of information about the battery's status,
ao charge current, but also remaining capacity, etc...
price for one is around 150 euro iirc
 
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