Capacity check of pc680

[PIN 37]

Can anyone tell me how to capacity check a PC680 battery? I have used a Concorde BC5000 battery cap checker but it gives results which are unlikely to be accurate since all the batteries I have tested using 16AH's as the setting show around 40% capacity and only 68% on a brand new battery.
Any ideas?

[rv7charlie]

Not enough data. Especially for those if us who don't have the Concorde cap checker.

You need to look at the load applied by the Concorde, then compare your results to the discharge curves on the PC680 spec sheet.

Remember, a 16AH SLA battery only has 16 AH of capacity when discharged at the '20 hour' rate of discharge (meaning that the 16 AH of capacity is spread over 20 hours of discharge).

Charlie

[Bicyclops]

I used a CBA 4 from West Mountain Radio and a Win 7 laptop to check mine. You can set the test up however you want to do it. I chose a discharge rate that matches what I would be pulling from the battery with the alternator dead and everything shut down that I didn't need. In my case, that's about 4.5 amps. I ran the test down to 10.5 volts which is conservative considering that my electronic ignition claims to run down to 5 volts. It ran for 2.75 hours and delivered just over 12 ah. At a higher amp draw, you can probably count on fewer amp hours delivered.

Ed Holyoke

Originally Posted by PIN 37

Can anyone tell me how to capacity check a PC680 battery? I have used a Concorde BC5000 battery cap checker but it gives results which are unlikely to be accurate since all the batteries I have tested using 16AH's as the setting show around 40% capacity and only 68% on a brad new battery.
Any ideas?

[lr172]

Originally Posted by Bicyclops

I used a CBA 4 from West Mountain Radio and a Win 7 laptop to check mine. You can set the test up however you want to do it. I chose a discharge rate that matches what I would be pulling from the battery with the alternator dead and everything shut down that I didn't need. In my case, that's about 4.5 amps. I ran the test down to 10.5 volts which is conservative considering that my electronic ignition claims to run down to 5 volts. It ran for 2.75 hours and delivered just over 12 ah. At a higher amp draw, you can probably count on fewer amp hours delivered.

Ed Holyoke

Most lead-based batteries have an inverse relationship between amp draw and ah capacity. The higher the draw the lower the ah capacity. This is why manufacturer list a 20 hour ah rating; It looks better. Good companies will also list a 1 hour ah rating to help the consumer better understand the range of capacity in different conditions.

Larry

[tim2542]

http://www.odysseybattery.com/docume...M-002_1214.pdf

Back out one page from here for more technical info.

Tim Andres

[az_gila]

Simple, and cheap.

Using the data sheet of the previous post -

Buy a 12 volt 50 watt bulb such as this one at Home Depot or your favorite hardware store -

http://www.homedepot.com/p/50-Watt-H...9333/203001458

Use clip leads to connect the bulb to the charged battery and measure the battery voltage. Note the start time.

Wait until the battery voltage falls to 10 volts and note the time again.

A up-to-spec battery will last 3.5 hours per the data sheet. A shorter time is a loss of capacity.

[Aggie78]

When I was doing a lot of glider flying, it was important each season to start out with the firm knowledge of what the state of your ship's batteries were.

I found a test scheme by a fellow glider pilot out of Chicago to be cheap, accurate and effective and see no reason why it wouldn't work as easily on the PC-680 as it did the ones used in our gliders.

Two ways of getting to the test protocol, you can go here:

http://aviation.derosaweb.net

And scroll about 1/2 down the page to "Testing Batteries" or a direct link to the XL spreadsheet is found here:

http://aviation.derosaweb.net/batter...g_Template.xls

[David_Nelson]

Odyssey has a pretty good technical manual at http://www.odysseybatteries.com/docs...m-002_1014.pdf and http://www.aeroelectric.com/articles/battest.pdf is a pretty easy project to build.

[Mike S]

You might get some good info from this thread about the Odyssey battery.

http://www.vansairforce.com/communit...d.php?t=108220

[PIN 37]

Thanks for you input folks, as usual a most helpful group. It would appear that our problem was that we were using 16ah as our base of testing (printed on the label of the battery ) instead of 12.3ah as on the graph of the 680 battery ( from Odyssey ) on one of the links suggested. Interestingly on another Odyssey publication ( googled) the rating for a PC680 battery for aviation use is quoted at 12.7ah, hmmm, a little confusing but we will test using both figures and see what we get. I wonder why the label on the top of the battery says 16ah