Concorde Battery Expected Life

[Marauder]

2 hours ago, cliffy said:

Any of you with long term batteries ever do a capacity check at annual time?

You might be surprised at what you find. 

Remember, that batteries capacity is your lifeline if the alternator dies-especially at night!

Just because it starts the engine doesn't make it usable for keeping things going when needed. 

Day VFR no problemo, night or IFR (or both) way different story. Your life may depend on it. 

Absolutely. Being a primary glass plane without a second alternator/battery, I take it's health pretty seriously.

[RobertGary1]

Always do a capacity check at annual but I own a tester. The battery already has to come out to inspect the box for corrosion. 

After 3 years an aircraft battery should be replaced at first sign of trouble. Unless you're a betting man. 

-Robert 

[Aviationinfo]

Can someone describe how they do the capacity check?  I understand the requirement but I'd like to know the logistics---how do you come up with an amperage for it?   Do you just turn on a known combo of amperage draw users like landing lights and leave them on for a certain period, and then check the battery voltage?  The problem with that is that the amperage changes as the battery drains.    Are there machines that do this?

[PTK]

13 minutes ago, Aviationinfo said:

Can someone describe how they do the capacity check?  I understand the requirement but I'd like to know the logistics---how do you come up with an amperage for it?   Do you just turn on a known combo of amperage draw users like landing lights and leave them on for a certain period, and then check the battery voltage?  The problem with that is that the amperage changes as the battery drains.    Are there machines that do this?

http://www.concordebattery.com/otherpdf/5-0171.pdf

pg 1502.

[DonMuncy]

4 hours ago, Aviationinfo said:

Can someone describe how they do the capacity check?  I understand the requirement but I'd like to know the logistics---how do you come up with an amperage for it?   Do you just turn on a known combo of amperage draw users like landing lights and leave them on for a certain period, and then check the battery voltage?  The problem with that is that the amperage changes as the battery drains.    Are there machines that do this?

I built my own. It is not perfectly "constant amperage draw", but plenty close to determine the capacity.

[Jerry 5TJ]

5 hours ago, Aviationinfo said:

Can someone describe how they do the capacity check?  I understand the requirement but I'd like to know the logistics---how do you come up with an amperage for it?   Do you just turn on a known combo of amperage draw users like landing lights and leave them on for a certain period, and then check the battery voltage?  The problem with that is that the amperage changes as the battery drains.    Are there machines that do this?

The test calls for a constant current load at the 1 hour rate.  To pass the battery must source that current at above the minimum voltage for 80% of 1 hour, or 48 minutes.  

My 24 volt battery is rated at 12 amp-hour capacity.  That's termed the 1 hour rate.  So the test load is 12 amperes.

Yes, there are electronic active loads built for the purpose.  Here's one. http://m.aircraftspruce.com/catalog/elpages/gilltct1000.php?clickkey=135734

More info in an easier thread on this topic. 

 

Edited February 14, 2017 by Jerry 5TJ

[Raptor05121]

I have a year-old RG-35AXC and it's also slow to turn over. The battery is 14.3v in flight, and 12.9 on the ground, so I think I have a bad ground on the starter. You might have the same. Mine flies 3x a week, hangared in Florida.

[Marauder]

On 2/13/2017 at 7:56 PM, Jerry 5TJ said:

The test calls for a constant current load at the 1 hour rate.  To pass the battery must source that current at above the minimum voltage for 80% of 1 hour, or 48 minutes.  

My 24 volt battery is rated at 12 amp-hour capacity.  That's termed the 1 hour rate.  So the test load is 12 amperes.

Yes, there are electronic active loads built for the purpose.  Here's one. http://m.aircraftspruce.com/catalog/elpages/gilltct1000.php?clickkey=135734

More info in an easier thread on this topic. 

 

Hey Jerry! Maybe you and Don could go into business and build us a "Cheap Bast$#d Battery Test Box"? 

[Marauder]

1 hour ago, bluehighwayflyer said:

I'm ordering a new Concorde RG35A battery tonight. On my flight this morning she turned over slowly, which is unusual, but fired on the first blade or two, which is typical.  I'll take the hint.  This RG35A was installed 5 1/2 years ago and has received no maintenance, but it has also never been fully depleted and has been flown regularly.  The plane is hangared in Florida.  Just another data point. 

I just hooked up my 12 year Concorde RG-35 to the BatteryMinder (its getting cold here again!). I think it helps, but I also sweet talk my battery and massage her terminals to let her know she is loved.

[MBDiagMan]

I went through Gil's fast on my 140.  I put in a Concorde Sealed three annuals ago and it is till very strong.

 

[mike_elliott]

11 hours ago, bluehighwayflyer said:

Hi, Chris. Yes, after reading this thread it looks like you guys with battery minders are getting better life out of your Concordes than are those of us without.  I have always been skeptical of them but am reconsidering. RG35As have gone up $100 in price since the last time I bought one. Maybe it is time to get onboard. 

Jim, take Sept 29th - Oct 1 off this year, come to the Mooney Summit and win a concorde and a batteryminder to boot!

[rbridges]

my concorde is 5 years old.  I've kept a float charger on it, and it's doing great.  My IA left the master switch on last year and drained it to nothing.  Charged it back up a few days later, and it hasn't missed a beat.  Keeping my fingers crossed.

[Mooneymite]

I have access to a battery capacity tester which can be used at annual time, but I'm  wondering why one couldn't  turn on all the typical load items (radios, lights, etc) that would be used in a loss-of-alternator-at-night scenario and see if the battery can carry it for 30 minutes without significant voltage drop.

Wouldn't this be a practical way to ascertain battery health?

Even a caveman could do it, right?

[MBDiagMan]

Yes, some calculation could be done and you could measure battery capacity if you have a way to measure current that high, but as long as the battery will hold a charge and get the job done, the exact capacity is what it is and you won't change it.  If it won't hold enough charge to start the engine after sitting a few days, replace it as long as you know that there is no parasitic drain.

battery life depends on a number of things, over voltage charging will shorten battery life and is easy to check.  Simply check the voltage across the battery before start up.  Charge it if you need to such that the battery with no load is measuring about 12.6 volts or thereabouts.  Then start the engine with the voltmeter across the battery.  With engine running and heavy loads turned off, you should see something on the order of 13.5 to 14.5 volts.  If the voltage is much more than 14.5 the battery is being fried from excessive charging voltage.

These voltages are not exact, but general, rather than specific to the aircraft, but you should be able to tell from these numbers if you are over charging thus decreasing battery life.

hope this helps.