Alternator CB popped

Hcsims

Filing Flight Plan
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Hcsims
I am looking for info/advise for my alternator CB popping situation.
The day before I was to leave for KOSH I was taking my AA5B out for a 1 hr flight. It started normally and during the run up I noticed the battery discharging. I cycled the alternator switch and then saw the alternator CB popped. I reset it and noted the battery charging rapidly and then winding down to a normal rate. I flew a 1.2 with no issues and a charged battery. I put the plane up and loaded for a 4am dep to KOSH. At 4 am when I tried to start, the starter engaged and after 2 blades stopped. After that I could just hear the bendix spinning and no engagement. This is a Sky Tec Starter that is 14 hrs old. The battery is a Concord that is 8 months old.
So my question is this, could the start the day before have been the batteries last gasp and the alternator breaker tripped during start? Or could there be a worn out starter that spiked the alternator? I have been starting with both masters switches on. I did find out the battery under load failed the test.
So I will replace the battery. What does anyone else think about the starter or alternator?
 
Replacing the battery may be all that's required but I agree with Doug that confirmation of the alternator charging is necessary.
 
Which alternator breaker? The 5-amp field breaker or the 60-amp output breaker?
 
The battery's purpose is to crank the engine. The alternator charges the battery and supplies electrical power while the engine is running. If your battery failed the load test, it likely has a bad cell or two. Be sure to monitor the voltage after the engine starts to confirm the alternator is charging.

I accidentally deleted my previous post...sorry.
 
Pretty unusual for a Concorde to go bad that soon unless there is something killing it (ghost loads in your electrical system, forgetting to kill the master, dropping it, over-servicing, etc.) Concorde has very specific instructions for maintaining and servicing the battery in the cmm that should've come with your battery. A recovery charge may be in order.

Also, if you leave the motorcycle trickle charger you snagged online for a song on your aircraft battery every night even in the summer...you're going to spend a lot of money on batteries
 
We did have a very harsh winter in Texas this year. 3 days of 0 degrees.
 
I can see I am charging. I have a Dynon SkyView with engine monitor
Pretty unusual for a Concorde to go bad that soon unless there is something killing it (ghost loads in your electrical system, forgetting to kill the master, dropping it, over-servicing, etc.) Concorde has very specific instructions for maintaining and servicing the battery in the cmm that should've come with your battery. A recovery charge may be in order.

Also, if you leave the motorcycle trickle charger you snagged online for a song on your aircraft battery every night even in the summer...you're going to spend a lot of money on batteries
i don’t do the trickle charger anymore other than a very short period.
 
Could be the voltage regulator going out as well. Have your A&P check that, we recently replaced ours.
 
It takes a really flat battery to make the alternator pop that breaker. Normally, a badly sulfated battery that has had the sulfate break off the plates and settle to the bottom of the cells and short the battery. That will show up as a pegged ammeter right after startup. Very rare. A bad voltage regulator that lets the alternator overcharge will also show up as a pegged ammeter.

So you either have an intermittent short somewhere between the alternator and its 60-amp breaker, or the breaker is bad. A short could be the output cable chafing on something and shorting to ground. Doesn't do the alternator any good, either. A bad breaker is usually an old breaker with oxidized contacts. Oxidation represents resistance, and resistance causes heating. Since the breaker measures current by running it though a slightly resistive bimetal strip, which bends when it gets too hot and pops the breaker, oxidational resistance leads to heating at lower current flows and a breaker that pops off too easily. A new breaker is the fix.
 
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