Electrical problem

[DonMuncy]

This is on my 231, but I believe the system is the same for both vintage and modern planes.

On getting ready to start me last flight, my starter would not engage. I thought the battery was down. I got the FBO to boost my battery, and the engine started. But even with the engine running, no other electrical equipment came on. Just as I was about to get out and check out the problem, I heard a "snap" and all the electrical came on line. Since it was VFR, I took off and flew home. 

Today I went out to the hangar to check out the problem. With the master switch on, nothing happens. I found the negative battery terminal pretty corroded, so I took the battery out and cleaned it up. The voltage was 12.5v. I put the battery back in, hoping it was just corrosion. Still nothing. I jumped into the battery connection with my car battery and could hear the relay click (the one which allows the boost power to reach the battery). 

Still nothing when I turned the master on.

While tinkering with it with the master turned on, I can hear a sound kinda like a hum, coming from the area of the main relay (the one which allows the battery power to activate all the electrical equipment). This convinces me that relay is trying to pull in, but doesn't. I take the relay off, figuring it is almost certainly bad. On the bench, it works when the same battery is hooked directly to it. I try it a dozen times and it works every time.

At this point, (before I pull out the wiring diagram), I figure either the relay is bad, but sporadic or whatever gives it its power is defective. Without knowledge, it would seem that the master switch must receive power independent of that relay and send it back to the relay to activate everything. 

Is this thought process correct? Anyone seen this before? Should I suspect the master switch? Any help before I start tracing out how the system works.

 

  

[N601RX]

If its like the older models, master relay coil is supplied +12VDC via a short wire that loops back to the relay post that connects to the battery.  The Master switch is connected to the other side of the coil and pulls it down to ground to make the relay come on.

[N201MKTurbo]

Measure the voltage to ground on both coil terminals of the master relay with the master switch on. One terminal should be near zero and the other should be near 12V.

 

If the ground side is higher than ground then there is a problem in your master switch. If the other side is lower than 12V then there is a problem in the battery side.

[DonMuncy]

And I assume if one side is close to 12 and the other close to zero, then it is the relay?

[MB65E]

Hi Don!! Have the battery load tested. Mine would charge to 12.5 but would fall on its ass when a load was put on it. Most 12v aircraft batts should always measure 12.5 or greater when fully charged. More like 12.7 is a good number. I spent a better part of a week trying to diagnose mine. Tricky electrical things would happen that made me think it was the realy too. Exact senario, my relay would close and work properly with out a load on it. As soon as any load was put on it, it would fall off line...

Another thing you can do if the relay does stay closed is pull all the CB's. Then turn the master on, systemically turn on each CB and switch on. Then get ready to watch the voltage fall off rapidly.

Finally put a new RG-35xC in solved my issue. But not after I spent $200 on a new master relay. Good news is I have both now.

-Matt

[DonMuncy]

Thanks for all the help. As it turned out, it was/is a defective battery. The thing that threw me off was when I jumped it from the car battery and it still did not work. Apparently i didn't have a good connection somewhere.

[carusoam]

For the record, Don...

How old was the battery?

Who was the manufacturer?

Best regards,

-a-

[DonMuncy]

It is a Concorde 35AXC. It was installed 4 years and 5 months ago. I have kept it on a BatteryMinder continuously, except for a few "out of town for a few days" trips. I am in Dallas where the temperatures are pretty high, and always hangared.

I am a little disappointed as I anticipated that constant BatteryMinder and Concorde would have gone longer. It is likely the BatteryMinder folks are going to tell me I should have had their Concorde specific unit, rather than the older unit I used.

[Marauder]

One thing that kills these batteries is sulfation. There are several good articles on what it is and what to do about it. Here is one:

http://www.batteryminders.com/avoid-battery-sulfation/

[DonMuncy]

That's what I thought I was using the BatteryMinder to avoid.

[Marauder]

That's what I thought I was using the BatteryMinder to avoid.

Depends, many of the older BatteryMinder units don't have the desulfation feature.

[M20JFlyer]

I would be interested if any one learns or knows:

What features does the Concorde specific ( BatteryMinder) provide.?.

VDC ELECTRONICS, INC brochure lists the model I list below to be a maintenance battery charger- De-Sulfator

This was the unit aviation consumer praised as the "best " approx four years ago.

Like Matt I hangar my 24V J in TEXAS where summer heat plays havoc with batteries.

My Concorde AGM IS FOUR YEARS AND three months as I write and has had the BatteryMinder attached when I am not traveling.

For four years I have owned and used the first generation 24 volt Plug 'n Run model 24041-AA-S2 VDC BATTERYMINDER

To date I am a Concorde fan but .. NOW .. New price of C AGM IS 0ver $ 550amu

pat 832.655.4203

[ArtVandelay]

The Concorde version uses different voltage settings for charging. If you are flying regularly I would not use any supplemental charging, some say it's not good for the battery to always be under charge, but it also masks a bad battery

[M20JFlyer]

Has anyone else probed around the .. battery stuff.com site?

I am on an I-pad an I can't make it friendly to copy and paste the link

this site has some very insiteful stuff on aviation batteries and all types of batteries.

The comments section has some good stuff also.... if you weed thru the weeds!!

[M20JFlyer]

Teejay

Yes I have also read the comments on constant maintenance being damaging.

The rock an hard place is can you harvest sulfation if you use a very low pulsing technology. VDC indicates theirs is using a pulsed source. Above my pay grade to decipher the technology

I must admit how does one commit to SOO many

Thanks for the feedback

Pat

[Guest]

It is a Concorde 35AXC. It was installed 4 years and 5 months ago. I have kept it on a BatteryMinder continuously, except for a few "out of town for a few days" trips. I am in Dallas where the temperatures are pretty high, and always hangared.

I am a little disappointed as I anticipated that constant BatteryMinder and Concorde would have gone longer. It is likely the BatteryMinder folks are going to tell me I should have had their Concorde specific unit, rather than the older unit I used.

Did you every have a capacity check carried out during annual inspections?

Clarence

[mike_elliott]

It is a Concorde 35AXC. It was installed 4 years and 5 months ago. I have kept it on a BatteryMinder continuously, except for a few "out of town for a few days" trips. I am in Dallas where the temperatures are pretty high, and always hangared.

I am a little disappointed as I anticipated that constant BatteryMinder and Concorde would have gone longer. It is likely the BatteryMinder folks are going to tell me I should have had their Concorde specific unit, rather than the older unit I used.

Don that's probably true. They make specific models for specific batteries, because of the charging voltage of the batteries. Chances are your older unit overcooked your concorde. Nice thing about these VDC electronics is if you have an aviation specific charger for a Gill battery and later replace it with a concord, they will trade them in no charge

[Marauder]

Don that's probably true. They make specific models for specific batteries, because of the charging voltage of the batteries. Chances are your older unit overcooked your concorde. Nice thing about these VDC electronics is if you have an aviation specific charger for a Gill battery and later replace it with a concord, they will trade them in no charge

I own one of the Concorde specific chargers. Another thing it has is a temperature probe to help determine what level of charge is needed based on ambient temperatures. The technology has come a long way since throwing an old Die Hard charger on things.

[DonMuncy]

Clarence,

I don't think the battery was ever capacity checked. I never saw it on a log book entry or an invoice, and I assume if they did it they would have noted it. 

[drbob]

Don:

     Concord:

   When these 1st came out they were/are highly regarded (compared to what they replaced) so I got one.

Eventually it failed --too soon I thought, so  opened it up, completely dry inside.

Added distilled and it came back.

Don't think in it's location near the cylinder head, it was ever very happy --very hot enviorment.

    Might be worth a look, probably dry inside.

   2C's worth.    drbob

[DonMuncy]

I asked Concorde about what they recommended for extended life on their RG batteries, telling them mine failed at a little over 4 years.  Their answer didn't address the question but said they recommend replacing their batteries at 4 years and that the real enemy of the batteries is vibration, from flight and landings. 

[drbob]

Open it up'

                  if it's dry inside vibration didn't cause that.

[larryb]

I have a boat. I used to have to replace the battery every year. Then I got an Optima, which is the same technology as a Concorde. It lasted 10 years. I just replaced it. Not because it didn't work. But because I was worried it was too old. Moral of the story: flooded batteries do die in high vibration environments.

Sent from my iPad using Tapatalk

[drbob]

Don:

  My bad,

     I thought this was a sealed  RG [Recombinant gas] battery, not flooded.

Concord sells (RG)  as Aerobatic, mountable in any positionand & vibration resistant, due to fatigue resistant plates.

    My faiure was due to recombinant catalyst not returning the H & O2 back to thecells,

    solar recombinants also have this problem, which Hyra-caps help to solve. 

Adding water reversed this.

                                                           drb