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Panama Red · 10-15-2014, 01:59 PM

You should be able to download a spec sheet for your battery from the manufacturer...

-Red

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cwf · 10-15-2014, 02:11 PM

GOOD BATTERIES!!

But you don't know the whole story..

One way to 'check' your systems... but not the only one... based upon your ticket above, you have over 500 AMPs...here is yet another link to 'convert' watts/amps/volts... How to Convert Watts to Amps Simplified -- Converting Amps to Watts the easy way

So, using 500 AMPS x 12Volts = 6000 watts.

If you put an 'ammeter' in the circuit, you can read the loads easier.. but, doing the 'test at load' as mentioned below will give you a 'ballpark' of your capability and longevity on the batteries and YOUR system.

Before you head out... for a "test".. start up all the 12V goodies... check voltage when all 'load' is on the batteries... run for an hour... check voltage.... repeat for 6 hours. Compare the voltages at each hour.. When you go 'boon docking', check voltages every couple of hours.. I bet you will find the voltages hold up pretty well...unless you are running extra loads like the heater.

lewster · 10-15-2014, 02:12 PM

Sorry, but 'Myron' should change his name to 'Moron'!!! Deep cycle batteries are not measured by either CCA (cold cranking amps) or MCA (marine cranking amps). They are measured by the amp/hour capacity at a stated rate of discharge (usual standard here is the 20 hour rate).

Your battery manufacturer should have a table that tells you what the residual voltage should be after a known discharge using the 20 hour rate. Cranking amps is meaningless!!

Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357

PharmGeek · 10-15-2014, 02:21 PM

They just can't keep good help these days

I told the dude about the boiler - I mean converter and he quickly said "you didn't add water to em did ya?!"

He went on about how many are meant to "vent" or some such...

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PharmGeek · 10-15-2014, 02:26 PM

Well - at least I think I can say the cells are not damaged.

I need to look up that table and I will run some load on the batteries and see how they act

I know 2 weekends ago they did the job no problems but that was a short weekend trip and I ran the generator a couple hours once as well

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perryg114 · 10-16-2014, 06:09 AM

Make sure you only add distilled water not tap water. Actually running a CCA test might damage a deep cycle battery. Find a dummy load and run a test like I outlined above. It at least gives you a relative indicator of the capacity left in the battery. Here are some curves on batteries discharge. Try not to geek out. If you can find a large high power resistor you can use that but it will get hot.

https://images.search.yahoo.com/sear...scharge+curves

You need one of these. You can adjust the resistance from 25 ohms on down to get the load you want. You can measure current using ohms law and measuring the voltage drop across the resistor. I=V/R and also measure the voltage across the battery. P=IV to get the watts dissipated in the resistor. You need to keep track of the hours it takes to get the voltage down below 11V or whatever the manufacture considers dead.

http://www.ebay.com/itm/NEW-25-Ohm-1...item3ce96ba246

There are some USB data loggers on Ebay cheap but they have a 5V max input voltage. You could make a simple voltage divider circuit to drop the voltage to where the data logger can handle it. It all depends on how much time you want to spend to get your answer.

I would setup a Labview program to do this, if I were at work.

Perry