Battery capacity - Elecsol

[roly_voya]

I also looked at these and contacted them to ask about cycle data, preferably graph, showing no of deep cycles tollerated. They where not keen!!! This seems to be just an expensiver leisure batt as someone says aimed at motor homes etc not marine deep cycling.

Part of the problem may be your measurment, if you take the reading with any load or just after switching off that is not a true 'at rest voltage' the batt has to rest for quite a while and the voltage will go up a small amount so I suspect you think it is flatter than it actually is.

 

[Anonymous]

I think that problem is that the OP's batteries are not being charged. If you switch off the generator as soon as 14.4V is reached, regardless of the charging current, you might only be 30% charged - it's impossible to know even approximately.

 

[Chris_Robb]

>I don't follow your remark about not noticing "the consumption/voltage ratio", can you explain? <

meaning that as the main alternator was not charging, and by charging only once a day on the generator, I could see directly the amps taken for the whole day, what was put back. we charged in the morning aiming to put back in the number of amps taken out. I know my measurements were not scientific, but we were on shore power for one day, which should have given a full charge, but 50 amps drawn late (average 2 amps per hour) the batteries showed a resting voltage of 12.2V (having been rested for 10 minutes from any discharge.) That made me wonder what the real capacity was. That and the inherant distrust of elecsol - and good old yachty paranoa sets in!

Anyway - a real pro is looking at the system tomorrow - lets see what he finds.

So

 

[Anonymous]

Glad you've got a pro coming tomorrow. I would help to use the standard terms -

Amperes = Amps = A= flow of current as in Ohm's Law V=IR where V is volts, I is amps and R is resistance

Ampere hours = Ah is related to a quantity of energy that has been put into or taken out of the battery.

The problem with these advanced meters is that no battery is 100% efficient so if you take out, say, 100 Ah you have to put back in, say, 130 Ah to charge it back to the same point. It isn't a fixed percentage and depends on a number of variables and it isn't the same for all batteries - and it doesn't even remain constant! So those meters can cause more trouble than they are worth when people start planning their charging round them.

Another point is that a battery has a different Ah capacity according to the rate of discharge. Mine, for example, are stated to have 180Ah at a 20 hour rate and only 135Ah at a 5 hour rate. A 20 hour rate means that the battery would be discharged 100% after that time and it is really only a theoretical number, you don't test it in practice. 180Ah discharged at a 20 hour rate is 180/20 = 9 Amps which is much less than you'd think, perhaps. I have three of those, so I can discharge at 27A and be within the 20 hour rate, i.e. expect the battery to last for 20 hours until 100% flat. I would never do that as it would damage the battery, I only ever discharge down to 50% so I could discharge at 27A for 10 hours and be 50% charge. Actually, that's about what happens on an overnight passage when I am running with all equipment running, cabin lights for those off watch, etc.

 

[captainslarty]

Must agree with orizabo... Mick..
Sterling have been Sterling imho. They produce a product that allows you to reuse old alternators at full potential and I have always found them good to deal with.
Re all lights flashing on the sterling reg.
Basically, and I have fitted too many of these to other boats to count /forums/images/graemlins/ooo.gif - the reg monitors alt votlage AND bat voltage. (I think from memory its the brown wire to the alt and the sensor at the bats) 17.5 and around 15 respectively as tripout failsafe. (all lights flashing ' alt overvolt) ALMOST always it is a cabling or connector problem. There is some bumf in the destructions, not in front of me at the mo, to fault find this occurance.
Feel the connectors and cabling, if hot track down, if I remember rightly you need to run the revs up to the point it just trips, measure the V drop between the alt and the battery, if greater than 2.5 if you use a diode splitter or more than 1 v in the cable if ya dont, it is almost certainly the installation.
Sterling aims at a market where people can fit their own unit inc mods to all kinds of alts.
IMHO a good fellow, cheap n chearful, but generally great, I love the chargers, prefer Balmar alts and regs though for me own yot. The 40 A charger is the same as the 50, or certainly mine is, runs at 50a for peanuts, safe and sound and well protected, bit flimsy on the connector cover though. but not really an issue.

Joe.. The sun has come out again in Galicia.. Praise be to God, She will provide.

 

[captainslarty]

Oh btw, Lemain (not sure of yer first name, but good to meet up), notice you are a Ham, G4XRZ here, whats your call, might arrange a sked, sorry, a wee bit off topic.....

Regarding the AH meters etc, if you use one from the same maker as yer charger etc, then the performance is not too bad, even from a different make the monitoring of V and knowing A by a shunt ' usually in the neg to capture it all, is pretty good. As said before, I like to use SG, Monitor, V and A and work it out for me self, which is probably the ONLY way to keep a handle on it all. But, like You n Mick, we have specific needs as liveaboards, we manage our own power requirements. For the average weekend yottie its probably not up in their list of priorities... ie, can I start the noisy thing, can I have me nav lights on etc. but, it becomes a very important aspect of day to day life if its all you own.
Be gads the rain degrades the wifi here over 1/3 mile lol... me crc errors are bettor, life is good.
Almerimar is great place, been there twice, how long you been there ?
Joe

 

[Anonymous]

Joe, That would be good but you are a long way away right now. A sked might be fun when you're ready suggest a frequency and I'll PM you my callsign. These Ah meters are not as reliable as you'd like for very good reasons....the first one is that none of them seems to go beyond Peurkert's coefficient in terms of corrections and that isn't far enough for cruising. I've almost stopped bothering with mine now...I know where I am with an accurate digital voltage and current reading.

David

 

[Gunfleet]

Chris,
SLightly off the point, I carry a spare alternator. It doesn't have to be very expensive. If you have a Bosch alternator, (for example) an alternator off a used Ford Escort diesel (usually abt 80 Amp) will fit and is ample.

 

[Chris_Robb]

Agreed - sensible thing to do. Also a spare starter motor...... just had to replace mine, but then it was 15 years old