HELP: Inverter is draining battery almost instantly! Why?

[lkruper]

My bad , just seed the charging table for this batt . Max bench charging is 8ah . So that would be ok with one panel.

Are you saying that one should not charge this battery any higher than 8 amps? His existing charge controller will exceed that. That seems very low, not even 0.1C. I am concerned that this might not be enough to fully charge with solar in one day, and the new battery will sit at < 100% charge for days at a time and sulfate again.

[Raul]

I found a numax catalog at thebatterycentreeversham co uk that lists the very battery and specs it says bench charging 8ah. It is a marine dual purpose 113 c20 and mca800a .

I'm confused as I got lead calcium dual purpose agm and take 22ah max charge and they only 90a c20.

[lkruper]

I found a numax catalog at thebatterycentreeversham co uk that lists the very battery and specs it says bench charging 8ah. It is a marine dual purpose 113 c20 and mca800a .

I'm confused as I got lead calcium dual purpose agm and take 22ah max charge and they only 90a c20.

I always look at the manufacturer's recommendation and I find that AGMs don't all have the same recommendations. In fact, I don't think I would buy a battery without first approving of the level of information in the technical guide and understanding it first.

[inetdog]

Some newcomers to the area will see a "maintenance free" battery and not realize that it is NOT a sealed battery at all, just a Flooded Lead Acid (FLA) battery with extra room above the plates for spare electrolyte and vent caps that are very hard to open. You can manage to open the valve covers and measure the Specific Gravity (SG) with a temperature compensated hydrometer.
It is totally different from a sealed (Valve Regulated) lead acid battery which could be either AGM or GEL type.

[lkruper]

Some newcomers to the area will see a "maintenance free" battery and not realize that it is NOT a sealed battery at all, just a Flooded Lead Acid (FLA) battery with extra room above the plates for spare electrolyte and vent caps that are very hard to open. You can manage to open the valve covers and measure the Specific Gravity (SG) with a temperature compensated hydrometer.
It is totally different from a sealed (Valve Regulated) lead acid battery which could be either AGM or GEL type.

Can you tell from this picture? http://leisurebatteriesdirect.ie/num...battery-110ah/

Here is the chart: http://thebatterycentreevesham.co.uk...cification.pdf

[spoon]

Can you tell from this picture? http://leisurebatteriesdirect.ie/num...battery-110ah/

Here is the chart: http://thebatterycentreevesham.co.uk...cification.pdf

So, now the thinking is that my battery is also no good as it won't take a charge above 8a? Seems strange that it would have such a low charging a.

I'm still holding fire on getting the victron 100/30 until I get everything correctly in place.

My Ctek 7 stage smart charger arrived though and has charged one of the Numaxs' really well, and it has held voltage no problem overnight... So some good news in that at least one of the batteries isn't duff, even if it is innappropriate!

[inetdog]

Can you tell from this picture? http://leisurebatteriesdirect.ie/num...battery-110ah/

Here is the chart: http://thebatterycentreevesham.co.uk...cification.pdf

There are a couple of good indications that this is really a flooded battery and not a true sealed battery:

1. magic eye charge indicator
2. Maintenance free

The second phrase is an indication that it is the high fill electrolyte, hard to open cap, variety of flooded cell.
The first tells us for sure, since a magic eye indicator relies on a floating specific gravity indicator, requiring free liquid electrolyte.

The bench charge rate is the C/10 rate (C₂₀/10) and you should not generally exceed this rate when charging.
For your battery this appears to be 6A, and if you put two batteries in parallel you would charge that bank at up to 12A.

The PDF also shows a range of VRLA (truly sealed) batteries in either AGM or GEL type. AGM is the one which is good for RE applications. GEL batteries are too easily damaged by high charging current.

[spoon]

There are a couple of good indications that this is really a flooded battery and not a true sealed battery:

1. magic eye charge indicator
2. Maintenance free

The second phrase is an indication that it is the high fill electrolyte, hard to open cap, variety of flooded cell.
The first tells us for sure, since a magic eye indicator relies on a floating specific gravity indicator, requiring free liquid electrolyte.

The bench charge rate is the C/10 rate (C₂₀/10) and you should not generally exceed this rate when charging.
For your battery this appears to be 6A, and if you put two batteries in parallel you would charge that bank at up to 12A.

The PDF also shows a range of VRLA (truly sealed) batteries in either AGM or GEL type. AGM is the one which is good for RE applications. GEL batteries are too easily damaged by high charging current.

So, essentially this battery is no good for the purpose I am using it for. Even less so if I change CC's to the victron 30a?

[Raul]

That's good to know , magic eye indicator has to float on electrolite . Makes sense that the chances are is fla. Thank you Sir for this info , you learn something new every day .Thats why I like this forum with lots of knowledgeable people .

[spoon]

That's good to know , magic eye indicator has to float on electrolite . Makes sense that the chances are is fla. Thank you Sir for this info , you learn something new every day .Thats why I like this forum with lots of knowledgeable people .

It is fantastic, I've learned so much... very quickly. So am i right in thinking that I actually need a battery with a bench charge rate of 30a to be of any use wit that victron CC?

[Raul]

You not gonna see 30a from even 2 panels let alone one in this wether . What you need is a good reliable cc and a second panel . With 2 panels you barely gonna charge 1 batt until March April .
I hooked 3x300w on my workshop and I get max 12-16a in this wether . In the summer I will do fine with just one .
You need a cc to take it and to do a proper absorb otherwise your battery will be undercharged everyday .

[spoon]

You not gonna see 30a from even 2 panels let alone one in this wether . What you need is a good reliable cc and a second panel . With 2 panels you barely gonna charge 1 batt until March April .
I hooked 3x300w on my workshop and I get max 12-16a in this wether . In the summer I will do fine with just one .
You need a cc to take it and to do a proper absorb otherwise your battery will be undercharged everyday .

Sorry, I've just got to try and simplify everything to be sure I'm getting it right. The crux is that, even with my current batteries, I should go for the 100/30 victron CC and the second panel?

Even though with the current weather it may not ne enough to fully charge by 110ah battery everyday, that setup is the best chance I have at the moment.

[spoon]

It wouldnt hurt to check the Voc of your panel (not sure if that has been posted here yet), as long as it is less than 37V you would have the option of hooking up 2 panels in series, or parallel, if Voc is over 37V parallel only.

Just checked and the panels (s) are actually 235w and VOC of 36.8v.

[lkruper]

Sorry, I've just got to try and simplify everything to be sure I'm getting it right. The crux is that, even with my current batteries, I should go for the 100/30 victron CC and the second panel?

Even though with the current weather it may not ne enough to fully charge by 110ah battery everyday, that setup is the best chance I have at the moment.

The instructions in the first link I provided from Numax in a previous post warns against overcharging the battery. You should not charge over a certain amperage for this battery (usually C/10 for a flooded battery, but the table in the second link is even lower for some reason) but don't have enough sun in the winter to get a full charge at the lower amperage. So you cannot charge at a higher rate to cram in all that power if you exceed what the battery can handle or you will damage it.

There is another possibility that might help you. The insolation numbers assume that the panels are being put on the roof of a house. I don't think that is the case for you, is it? There are some sites for calculating not just by location and direction (eg S) but on the angle of the panel. In my case the winter insolation would be 2.82 but if I place the panel at an angle optimized for the winter sun it goes up to 5 or so. I think this link should do this for you: http://www.solarelectricityhandbook....rradiance.html

Finally, getting a generator to make it through the winter would also be a possibility.

[spoon]

The instructions in the first link I provided from Numax in a previous post warns against overcharging the battery. You should not charge over a certain amperage for this battery (usually C/10 for a flooded battery, but the table in the second link is even lower for some reason) but don't have enough sun in the winter to get a full charge at the lower amperage. So you cannot charge at a higher rate to cram in all that power if you exceed what the battery can handle or you will damage it.

It has C20 on the side of the battery, along with the other specs... So I'm confused as to what the actual safe charge ampage is. As on the data sheet it says 8amp?