Waynerrr

Thank you everyone, I appreciate the replies, very useful. Smileypete - I've ordered the 30A Elecrotroquest charger you posted a link for.

Actually, I think I get it. The one that says 25-80Ah for capacity has a charge rate of 7Ah. Going by that article that's between a figure of about 25%-10%. The writer recommends 30%-50% which would mean I need a charger with a charge rate of 100Ah to get roughly 30%. All that said, is 330Ah excessive with so few 12v systems? Seems it would be cheaper to reduce the size of the bank and go for a smaller charger?

Thanks Andy, that is an extremely useful read. However, it doesn't mention the capacity rating I'm referring to that's mentioned on the Numax chargers. The article seems to discuss charge rate vs battery capacity which is the bit I understand.

Hi all. Hopefully someone can help explain what some of the figures quoted on battery chargers mean. For example, this Victron charger states it will charge '12V, 25-80Ah battery'. Does the 25-80Ah mean it will only charge a battery (bank) up to 80Ah? I have 3 110Ah batteries - will this charger not work for me? This Numax one states 100-200Ah so this is nearer the mark but still not 330Ah. Do I need to find one rated above 330Ah? The other figure I see is the charging rate - in the Vectron above I believe it's 7Ah - I understand that to mean to fully charge my 330Ah bank from empty would take 47.1 hours. So, when I see more expensive models, the charge rate is usually higher because that happens quicker/for efficiently. At home I have a Halfords battery charger that cost me £40. What's to stop me connecting that to a 240v socket and to the batteries and leaving that on? There's no mention of capacity on it and the charge rate is 8Ah. I appreciate this might be a silly question but I'm confused as to why the capacity is important. Lastly, my boat is now in a marina on hook-up and the only 12v systems are the LED lights, water pumps, Mikuni calorifier ignition/pump and the radio - do I really need a 330Ah bank?! Thank you.

It's definitely an inverter and charger but likely quite old (which could be the problem). I haven't thought to check for a fuse on the unit itself as it's fitted to the wall - I'll take it off for a better look. Good idea to check the power through the unit as well, thanks.

I have a 600w Sterling inverter/charger combo. I've never used the charger before because I used to continuously cruise. However, now I'm in a marina I'd like the charger to charge the batteries off the shore line. Problem is, it doesn't seem to be doing anything. It appears to be wired correctly as per the instructions I have. It only has one switch, On/Off and two lights, Inverter and AC Power. When the switch is on, the red light comes on. When Off, no lights are on. Here's a diagram of the wiring: The inverter has the 12v + - going to/from the batteries. There is also a 'Mains' cable coming in from the fuse box. This makes sense because the power comes in from the shore line (via the switch), into the fuse box then out to the inverter which should charge the batteries, right? So, is it a) wired wrong or broken?

This sounds exactly like my afternoon, albeit with 60l of water I've removed so far with a mop and bucket. Like you I'm fairly sure the pipes aren't to blame having done similar tests. I'll be taking another look tomorrow to see if there's any more. The idea about overfilling the water tank is an interesting one as it fits with the time-scale, although I've never noticed this in the past. The water I've been taking out is dark brown, either canal coloured or rusty bilge type water, I can't decide. If the leak has stopped and I can no longer get any more out with the mop, would anyone recommend using a dehumidifier? The only issue I can think of is they need to be run constantly and probably require a fair amount of power.

So I managed to fit this as suggested and it did indeed appear to work, however (predictably), the monitor is giving out some odd readings. SOC doesn't really seem to change despite the V going down. The volts go down so rapidly I think the batteries are FUBAR. I had 3 LED lights on for an hour plus I ran a jigsaw off the inverter for about 5 minutes: the V went from 13.2 to 10.6 (but the SOC remained at 100% - it only went down to 99.3% when I was charging the batteries!). So, is the monitor behaving oddly because the batteries are knackered or is there another reason? Incidentally, I sync'd the system when it probably wasn't fully charged.....

Great, thank you all

Thank you all, I think I understand. I've done a couple more diagrams just to see if I understand it correctly. I think they're basically the same but one would be easier for me as I don't have to buy any more cables. Method a https://www.dropbox.com/s/us14hxqi5agmn3i/bmv_2.png Method b https://www.dropbox.com/s/48yagae5ej4fct4/bmv_3.png If neither of these is correct I'd really appreciate a diagram similar to mine The only thing I'm not clear on, especially after reading smileypete's reply, is where do I put the solar panel negative? To the battery bank or to the opposite side of the shunt? Many thanks

Ok, thank you very much both, that sounds a lot clearer now.

I saw that, thanks. So how would I connect the shunt then? Keep the batteries as they are in method 1 in the link you provided and they simply feed the shunt off of it? Currently I'm running the negative through the shunt which now looks very wrong. This is a diagram from the manual http://www.victronenergy.com/upload/documents/Battery%20monitor%20quick%20install%20guide_REV10_05-07-2007.pdf

This is how they're connected to the shunt (this doesn't include the starter). https://www.dropbox.com/s/n6ltojoarwow00s/bmv_ne.png