Johny London

Look, it's simple. I have a fridge running 24/7, off a victron 3000 inverter, also on 24/7. On average the fridge uses a couple of amps an hour, the inverter maybe 1/2 amp or so. Thats say 60-65 amps of battery current/power call it what you will, in a 24hr day. Lets say with a bit of laptop time, shower pump and led lights - oh and a couple hours using my 240v stereo amp that I'm using 90amps a day. My batteries are 4x100amp. So I can usefully use maybe 200amps?. Therefore they should easily last a couple days, maybe three if it's not been hot and I haven't been "living like that". The alternator is 175amp (for the domestic batteries, the starter has its own). I would have thought that the alternator would have put out say 100amps even on tickover, hence I thought a couple hours would be adequate to recharge, given that on many days I have been cruising for a lot longer than 2 hrs. I didn't have a convenient means of keeping an eye on the state of charge - now I do. Thinking about it, I got into a bad habit - I frequently had to leave the boat to return to London and attend to my affairs, I would go late morning/early pm, and leave the batteries as they were, ie prolly not that well charged having been using the fridge etc over night. Upon my return always gave the engine a good run because I not only wanted power, but hot water. It had seemed wasteful to run the engine before leaving the boat and the tank of hot water. We've all had car batteries go dead flat - leaving lights on, electrical gremlins, whatever. Sometimes you recharge the battery and its fine, but usally if its a bit old then a few days later it goes flat again so you buy another one. These batteries were so new that I assumed they would have a bit of leeway in them, I was quite to prepared to replace them a little early ie 18 month, couple years. I didn't realise they were so fragile. Now, thanks to you all, I do. I was hoping someone would have a remedy or perhaps suggest I had a failing alternator or whatever, that's why I posted. Simples. I apologise in advance if I've used the wrong units, mis spelt anything or upset anyone in any other pedantic manner Have to go now as the laptop battery is getting low....

Thanks for going to the trouble of finding that for me - I'm really after separate built in oven and built in hob though. I guess it's going to be a long old research for me too then! I'm surprised there haven't been lots of nay sayers regarding the domestic option! I'm really after something that suits my asthetic tastes but also covers the necessary boaty-ness! Thinking about it a single oven will do fine, especially if most of those with the two compartments are really just a grill/oven. I saw this... http://www.ebay.co.uk/itm/THETFORD-SPINFLO-DUPLEX-OVEN-GRILL-motorhome-caravan-boat-campervan-horsebox/131882580630?_trksid=p2055119.c100022.m2048&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20140122153843%26meid%3De73720f1dc0545c0b7b80fba7cc20165%26pid%3D100022%26rk%3D1%26rkt%3D4%26mehot%3Dlo%26sd%3D291730092051 Its in black but looks ok to my eye.

Hi Alan, I forgot to mention about the ffd - I'm aware of it already. I've got the space for 600mm, but actually it is good to know that if I do go 500mm I haven't burnt my bridges in the domestic camp

Hello again, everyone was so helpful with my battery issue, this time I thought I'd ask before the event rather than after though! I'm hoping to fit my kitchen very soon - at least get all the cabinets and worktops in (before I break off to paint the boat). I have it all planned, but need to decide on the size of space for the built in oven and hob. I'm not a fan of stand alone. I'm after something that looks as "normal" (ie domestic) as possible, and had thought to go with domestic appliances and just change the jets for LPG - I see both Ikea and Wickes include the different jets with their products, for a start. Then my mind turned to the digital display - easy, just get a basic oven. Then I thought about the ignition spark thing and after googling found that sometimes you can change that for 12v. Then, perhaps a final nail in the coffin for the domestic argument - the ovens often have a cooling fan that needs to run so as the controls don't start to melt, so again if its 240v could be a problem. Of course - I do currently have the 240v running all the time - courtesy of my Victron - I know that is another topic for some debate, and although I don't see the 0.5a (?) self consumption as too much of a problem, my instinct tells me to move towards 12v whenever I can. So - thoughts? Pros and cons? In particular - whats the best 12v oven and hob out there? I like chrome Thanks

Yeh, might start doing that for a bit - having the fridge just makes life that bit more civilised though, especially while it has been so hot. I think the fridge uses about 2 amps an hour so even with the added inverter drain, it's not that bad really. A while back I was using the angle grinder a lot though, so that might have been when the rot set in - was busy putting on good locks before bringing my main stuff aboard. So - what is the outlook for my batteries? Also, if they are down on capacity, will they re charge quicker now? If so might be ok to live with for now, long as they last 24hrs each time. Funny thing is the inverter low battery led has never come on (I think the inverter even shuts down). Got as low as 11.5v today late afternoon but I did a 4 hr engine run - will see if doing that each day can help a bit.

Yes it was a sailaway - with additions - fully working bathroom and wc and all the wiring tails in. I'm afraid a 240v fridge was all I had available to start with, so yes the inverter is on 24/7 and I know the self consumption of the inverter is over 1/2a. 12v fridge - yet another on my list of stuff to get and things to do. To be honest, If I'd gotten 18 months out of the first set of batteries, well by then everything else would have been in place (hopefully). Was hoping to buy a bit of time and I certainly can't do without a fridge on board Again, without a microwave my food choices are limited to what I can boil up

Yes, since I got the boat I have been busy organising letting my place in London so that I could go live aboard - solar panels - I see them all the time and what with all the hot sun this year I feel I've really been missing out. Right now I'm planning/purchasing/fitting a kitchen - maybe it's not as important as solar but man am I sick of cooking on the floor with a two ring burner! I just haven't had time to do even the really high priority things and had just hoped that things would be ok for a bit. Did I mention the boat needs painting before the weather turns!? So far I managed to build a frame for my bed, so I'm comfy in my cabin and not throwing the mattress on the floor each night, I also got a settee, set up a temporary wardrobe, fitted the inverter, lights, 240 sockets, curtain poles and retainers (and partly finished curtains. What a shame my new batteries have had it - just hope I can get some paint on before the rust sets in!

Hi and thanks for all the replies. I did not know that it was possible to kill new batteries so very very quickly. Since I got the boat I have been busy, cruising it across the country and doing jobs to it, as well as moving stuff aboard etc. Solar panels are high on my list, as is a generator, and some means of monitoring the batteries easily (I had a multimeter I could use for periodic checks). I just had not had the time to address these issues and thought that the batteries would be all right for a while at least, even if perhaps their over all longevity might get compromised. So - bad news for me then! I'll try charging for longer, see if I can recover them for a bit, at least carry on using them until I get sorted with a smartguage and bmv1 - I had not heard of these before and have bought a couple of volt meter lcd panels to hook up to both domestic and starter batteries, was next job on list. My engine has a separate 175 a/h alternator for the domestic bank. If I could get to a mains hook up I could use the sophisticated charging that the victron has to offer.

Hi All, I picked up my newly built boat in May. It has 4 leisure batteries (100amp hour according to the d of c though they are tricky to get at) and I fitted a Victron 3000 inverter/charger. Only ever used the engine for generating. These days, I'm running the engine for three hours a day and by the next morning the batteries are down to like 11.7 volts or less. The only thing on overnite (aside from the inverter) is the fridge which supposedly takes .52kw/h, and the microwave with its digital clock. I have two or three hours of laptop in the evening for tv etc, and an hour or two of music through a 240v amp which is turned off (not standby) when not in use. Microwave some times for 5-10 mins. The batteries didn't used to go this flat, I can't think what I might be doing differently to cause this? When I first had the boat I was cruising a lot more, though I'm not quite sure when this apparent discharge started. The fan belt squeaks for a minute when I start the engine but reads well over 14v when charging. A while after and they sit nice and high around 13v. Surely not knackered the batteries already???