Battery charger recommendations please

[MtB]

I've just fitted a new pair of domestic batteries to Aldebaran and am having difficulty charging them fully.

 

The Tracer solar controller shows them never rising above 60% charge and about 12.5v.

 

The engine has a 24v alternator and an electronic step down device which limits charging voltage to 13.4v. Not enough i suspect. So I think the best approach is to use my cheap chinese petrol generator to run a decent multi-stage mains charger for a few hours. But searching the boards for a sensibly-priced charger is a thankless task with results diluted with endless discussion of related, but different, subjects.

 

So can someone nominate a cheap-ish multistage charger capable of doing an equalisation charge on a pair of leisure batteries please? Or is this not possible using a cheap chinese generator producing probably a really dirty 240v waveform?

 

Any other ideas? No shore power availble.

 

Thanks,

 

MtB

[Phil Ambrose]

Oo er trying hard to remember the name, there was a thread recently about chargers and the Charger I use which is a Numax 30amp proved to be the same as another that was half the price. Mine cost about £150-00

Sorry that's not much help

Phil

[BEngo]

My Waeco 25 amp works happily on my cheap Italian genny. Hasn't got an equalisation setting tho.

 

N

[Kae]

13.4v is madness, it would take a very, very long time for your batteries to charge!

 

These are great: http://www.ebay.co.uk/itm/FULLY-AUTOMATIC-5-STAGE-MARINE-BATTERY-CHARGER-12V-30A-/141043954256?pt=UK_CarsParts_Vehicles_BoatEquipment_Accessories_SM&hash=item20d6dff250

 

They appear to all intents and purposes to be the Numax chargers, but without the label!

Edited November 29, 2013 by Kae

[DaveC]

13.4v is madness, it would take a very, very long time for your batteries to charge!

 

These are great: http://www.ebay.co.uk/itm/FULLY-AUTOMATIC-5-STAGE-MARINE-BATTERY-CHARGER-12V-30A-/141043954256?pt=UK_CarsParts_Vehicles_BoatEquipment_Accessories_SM&hash=item20d6dff250

 

They appear to all intents and purposes to be the Numax chargers, but without the label!

 

You will find that this item is a bit cheaper (about £3) direct from their own web site rather than ebay. I did!

 

 

Dave

[Canarrowboat TBD]

13.4v is madness, it would take a very, very long time for your batteries to charge!

 

These are great: http://www.ebay.co.uk/itm/FULLY-AUTOMATIC-5-STAGE-MARINE-BATTERY-CHARGER-12V-30A-/141043954256?pt=UK_CarsParts_Vehicles_BoatEquipment_Accessories_SM&hash=item20d6dff250

 

They appear to all intents and purposes to be the Numax chargers, but without the label!

 

Second vote for this one - got the 45A, 4 Stage one approx. a year ago (£135) - and had no concerns since...

[richardf]

Looks identical to my 30A Numax - which has always been great

[MtB]

Thanks for the recommendation. Doesn't claim to do an equalisation charge though, as far as I can see.

 

Maybe I'll just buy it anyway given that everybody seems happy with it!

 

 

MtB

[matty40s]

But searching the boards for a sensibly-priced charger is a thankless task with results diluted with endless discussion of related, but different, subjects.

 

 

.....never !!, really??

[Phil Ambrose]

13.4v is madness, it would take a very, very long time for your batteries to charge!

 

These are great: http://www.ebay.co.uk/itm/FULLY-AUTOMATIC-5-STAGE-MARINE-BATTERY-CHARGER-12V-30A-/141043954256?pt=UK_CarsParts_Vehicles_BoatEquipment_Accessories_SM&hash=item20d6dff250

 

They appear to all intents and purposes to be the Numax chargers, but without the label!

Yay! that's the one I was trying to remember.

 

Phil

[MtB]

.....never !!, really??

 

Yes!

 

I was wondering about searching next to see if there are any rules about having a home mooring, or not. will probably be a simpler subject to get some results on...

 

MtB

[Kae]

Thanks for the recommendation. Doesn't claim to do an equalisation charge though, as far as I can see.

 

Maybe I'll just buy it anyway given that everybody seems happy with it!

 

 

MtB

 

 

You're right, it doesn't, but with a two-battery bank and considering what you're (not) achieving at the moment, that's the least of your worries!

[MtB]

 

 

You're right, it doesn't, but with a two-battery bank and considering what you're (not) achieving at the moment, that's the least of your worries!

 

Yes but what about once I have them up to 90% charged, everyone will be tellin' me to do an equalisation charge once in a while!

 

Won't they?

 

MtB

[bottle]

Change the boat electrics to 24v and ditch the electronics.

 

[MtB]

And how will that help?

[bottle]

The 24v alternator will (should) give out more than 26.8v (13.4v), mine puts out 28.8v (14.4v).

 

So reducing charge time and getting the batteries better charged.

 

or if possible adjust the electronics to give out a better voltage. (this would be the simpler route)

 

Open wet lead will take 14.6v quite happily.

 

ps. changing the boat to 24v means of course changing all the onboards to 24v or putting some electronics after the batteries to drop down to 12v.

[MtB]

No equalisation charge still then!

 

But you have given me an idea... or maybe this is what you meant in the first place. Reconfigure the two domestic batts as 24v, install a split charging relay and use the 24v to 12v step down electronic devices to power the domestic electrics instead of them being used to charge the domestic batts as they are now. They can deliver 30 amps IIRC, plenty to run a fridge, a water pump and a few lights!

 

Now, how to equalisation-charge a 24v battery bank from a generator....?

 

 

MtB

[BD3Bill]

Hi Mike

 

Sorry if I'm stating the obvious or teaching Gran to suck eggs but….

 

Are you totally sure there is no drain on the batteries when you are not on board? i.e. properly isolated with no draw (such as an auto bilge pump for e.g. ) ?

 

Are the connections from the controller to +ve of battery 'A' and the -ve of battery 'B'?

 

Greg will let you put a charger and battery on the mains in the entrance hall there for a couple of quid you know.

 

Cheers

Bill

[MtB]

Hi Bill,

 

Yep, batteries cross-connected as you describe, and the auto bilge pump is the only device not isolated by the main isolator switch. Bilge pump is bone dry so I doubt it is running and using up the charge!

 

Will Greg let me run an extension lead all the way down to Thrupp do you think? Good idea for when I'm back though!

 

MtB

[BD3Bill]

Ahh!

 

My bilge pump cycles every minute or so, dry or not, which is why I asked (going to fit a float switch soon)

 

Enjoy them new gates on the way back up!

 

We gone up to Claydon now, on Greg's bit there.

 

All the best mate.

 

Cheers!

 

P.s. Fit a 12v alternator & keep it simple? I got a new 70amp A127 from ebay for £70 ish

Edited November 30, 2013 by BD3Bill