Arthur Posted October 29, 2022 Report Posted October 29, 2022 Replaced the ships battery with the Concorde RG 35AXC. Eight days later when the pitot static test was to be done the battery was dead flat.There was no activity for the plane and the master was off as was the interior light. Mechanic charged over night and tested no charge. Two separate multimeter tests revealed reverse polarity 12.5 Volts. Any thoughts? Their warranty procedure is a real pain. Quote
Ragsf15e Posted October 29, 2022 Report Posted October 29, 2022 25 minutes ago, Arthur said: Replaced the ships battery with the Concorde RG 35AXC. Eight days later when the pitot static test was to be done the battery was dead flat.There was no activity for the plane and the master was off as was the interior light. Mechanic charged over night and tested no charge. Two separate multimeter tests revealed reverse polarity 12.5 Volts. Any thoughts? Their warranty procedure is a real pain. Try calling them. Maybe get better results. Quote
1980Mooney Posted October 29, 2022 Report Posted October 29, 2022 (edited) 1 hour ago, Arthur said: Replaced the ships battery with the Concorde RG 35AXC. Eight days later when the pitot static test was to be done the battery was dead flat.There was no activity for the plane and the master was off as was the interior light. Mechanic charged over night and tested no charge. Two separate multimeter tests revealed reverse polarity 12.5 Volts. Any thoughts? Their warranty procedure is a real pain. Can you clarify: Did you test or start your plane after you (or mechanic) replaced the battery in order to verify it was functioning properly post installation? (right after install or some time before the static test) Did you verify voltage drop and amperage discharge when turning on anything electrical prior to engine start? Did the engine turn over strongly? Did you verify the alternator was charging after start showing positive amps as well as voltage of about 13.5 or more? You say the mechanic charged it and it tested "no charge" after charging overnight but also said 2 tests reveal "reverse" charge of 12.5 volts. "No charge" usually means dead flat zero "0". The 2 statements are in conflict. Did you turn on the Avionics Master when the battery was "reverse charged"? (Was the battery out of the plane when your mechanic charged it and when you tested reverse polarity? - or was it wired in the plane battery box?) Edited October 29, 2022 by 1980Mooney 1 Quote
EricJ Posted October 29, 2022 Report Posted October 29, 2022 3 hours ago, Arthur said: Replaced the ships battery with the Concorde RG 35AXC. Eight days later when the pitot static test was to be done the battery was dead flat.There was no activity for the plane and the master was off as was the interior light. Mechanic charged over night and tested no charge. Two separate multimeter tests revealed reverse polarity 12.5 Volts. Any thoughts? Their warranty procedure is a real pain. What does "reverse polarity 12.5 Volts" mean? Lead-acid batteries won't reverse polarity like a NiCd can, and even when NiCd batteries do it it's usually only one cell rather than the whole battery. I'm also not sure what "no charge" means after charging it over night, especially with the "reverse polarity" assessment. I'd be more suspicious that it was hooked up backwards than the battery has a problem. Either the battery or the charger and/or the multimeter may have been hooked up backwards. Either way, it may be an indication that you may want a different set of eyes on it. What part of the country are you in? 1 1 Quote
1980Mooney Posted October 29, 2022 Report Posted October 29, 2022 (edited) 1 hour ago, EricJ said: What does "reverse polarity 12.5 Volts" mean? Lead-acid batteries won't reverse polarity like a NiCd can, and even when NiCd batteries do it it's usually only one cell rather than the whole battery. I'm also not sure what "no charge" means after charging it over night, especially with the "reverse polarity" assessment. I'd be more suspicious that it was hooked up backwards than the battery has a problem. Either the battery or the charger and/or the multimeter may have been hooked up backwards. Either way, it may be an indication that you may want a different set of eyes on it. Battery sites say it is possible for a lead-acid battery to have a reverse charge but it can't do it by itself. It takes 2 things to happen with human intervention. "The only way for a battery that has a positive charge, to reverse itself, is for the battery to be completely discharged, and then reversed charged." That would mean after the battery was somehow fully drained the mechanic, while hooking up the charger, reversed the polarity when charging. Battery Myth | Can a Battery ‘Reverse’ its Polarity? (batterystuff.com) Battery Glossary – Reverse Polarity – BatteryGuy.com Knowledge Base I have a hard time seeing how a mechanic may have installed the battery backwards (hooked the battery cables up reversed) - the cables are not long enough to switch sides and the battery only fits towards the cables one way. If it was in fact reversed and fully charged at 12.5 volts when they powered the avionics on for the pitot static test (when the OP says it was discovered) then some of the avionics may be fried. Edited October 29, 2022 by 1980Mooney Quote
Arthur Posted October 30, 2022 Author Report Posted October 30, 2022 18 hours ago, 1980Mooney said: Can you clarify: Did you test or start your plane after you (or mechanic) replaced the battery in order to verify it was functioning properly post installation? (right after install or some time before the static test) Did you verify voltage drop and amperage discharge when turning on anything electrical prior to engine start? Did the engine turn over strongly? Did you verify the alternator was charging after start showing positive amps as well as voltage of about 13.5 or more? You say the mechanic charged it and it tested "no charge" after charging overnight but also said 2 tests reveal "reverse" charge of 12.5 volts. "No charge" usually means dead flat zero "0". The 2 statements are in conflict. Did you turn on the Avionics Master when the battery was "reverse charged"? (Was the battery out of the plane when your mechanic charged it and when you tested reverse polarity? - or was it wired in the plane battery box?) 1 New battery placed in aircraft 2 Starter would not turn over. 3 starter removed and failed test sent for warranty repair. 4.battery was tested for voltage and load at this time. 5. Decided to have pitot static test while waiting for starter return 7 days after battery installed 6. Battery would not supply power to transponder for test 7. Battery removed and charged by mechanic overnight. 8. mechanic said battery would not charge and would not operate his tester.. He demonstrated the tester on two other batteries and it worked properly. 9.Took battery and after leaving I decided to test on multi meter. Showed -12.5 10 . Talked to person who did the pitot test. He didn’t believe reversed polarity. Used his multimeter and got the same result. 11. based on my search and. Comments below I now believe the mechanic accidentally reversed the positive leads on his charger. 12 Still doesn’t explain how or why battery discharged. Master off and all other switches as well. Quote
Arthur Posted October 30, 2022 Author Report Posted October 30, 2022 1 hour ago, Arthur said: 1 New battery placed in aircraft 2 Starter would not turn over. 3 starter removed and failed test sent for warranty repair. 4.battery was tested for voltage and load at this time. 5. Decided to have pitot static test while waiting for starter return 7 days after battery installed 6. Battery would not supply power to transponder for test 7. Battery removed and charged by mechanic overnight. 8. mechanic said battery would not charge and would not operate his tester.. He demonstrated the tester on two other batteries and it worked properly. 9.Took battery and after leaving I decided to test on multi meter. Showed -12.5 10 . Talked to person who did the pitot test. He didn’t believe reversed polarity. Used his multimeter and got the same result. 11. based on my search and. Comments below I now believe the mechanic accidentally reversed the positive leads on his charger. 12 Still doesn’t explain how or why battery discharged. Master off and all other switches as well. On further tests this morning I am now the proud owner of a fully charged battery with reverse polarity. Quote
LANCECASPER Posted October 30, 2022 Report Posted October 30, 2022 14 minutes ago, Arthur said: On further tests this morning I am now the proud owner of a fully charged battery with reverse polarity. If you run it all the way down and charge it properly would it go back to correct polarity? Quote
1980Mooney Posted October 30, 2022 Report Posted October 30, 2022 1 hour ago, Arthur said: On further tests this morning I am now the proud owner of a fully charged battery with reverse polarity. 1 hour ago, LANCECASPER said: If you run it all the way down and charge it properly would it go back to correct polarity? Yes but the battery is permanently damaged. Battery Myth | Can a Battery ‘Reverse’ its Polarity? (batterystuff.com) For all intents and purposes, the battery will be ruined. You could technically charge it up, negatively, and continue to use it, but your plates are designed with the positive plates being lead dioxide, and the negative being composed of a sponge lead, which would now be reversed. Because the reversed battery is no longer formatted correctly, it will only work to a limited degree. The fact of the matter is, a lead acid battery cannot reverse its own polarity without an external stimulus. It is just not possible. Also Battery Glossary – Reverse Polarity – BatteryGuy.com Knowledge Base Correcting reverse polarity in a battery Where a battery has reverse polarity by error the following can correct it. Discharge the battery completely – connecting a low amp rated light bulb with no cut out circuitry should do this. Correctly connect a charger If the battery refuses to take the charge try a stronger charger for a few seconds (e.g. a 24 volt charger on a 12 volt battery) and then use the correct charger at its lowest settings. Note in all cases the life span of the battery will have been reduced as deep discharges damage internal components. 1 Quote
A64Pilot Posted October 30, 2022 Report Posted October 30, 2022 Just when you thought you had heard everything Quote
EricJ Posted October 30, 2022 Report Posted October 30, 2022 2 hours ago, LANCECASPER said: If you run it all the way down and charge it properly would it go back to correct polarity? No, it's damaged. Lead-acid batteries won't do this on their own and reverse-charging them damages them. It's no bueno, trash. Edit: To clarify, you can probably rehab a Lead-acid battery that has been damaged this way back to proper polarity, but it is damaged. When NiCd cells do this there is often a procedure to fix it and return it to service, usually by removing the reversed cell, discharging it, and then at least starting a charge in the proper polarity. Lead-acid batteries don't survive this without damage. Quote
LANCECASPER Posted October 30, 2022 Report Posted October 30, 2022 22 hours ago, Arthur said: Replaced the ships battery with the Concorde RG 35AXC. Eight days later when the pitot static test was to be done the battery was dead flat.There was no activity for the plane and the master was off as was the interior light. Mechanic charged over night and tested no charge. Two separate multimeter tests revealed reverse polarity 12.5 Volts. Any thoughts? Their warranty procedure is a real pain. I don't think this would be a warranty issue, since it's not a defect in materials or workmanship. Looks like just a mistake by the mechanic. Maybe he can cut you a break on labor. Sounds like originally though something drained the battery in the first week, hence the need for the charge. I would make sure once you get a good battery that you track that down or you'll be right back where you started. (Maybe a stuck relay?) 2 Quote
1980Mooney Posted October 30, 2022 Report Posted October 30, 2022 (edited) On 10/29/2022 at 12:08 PM, Arthur said: .... Mechanic charged over night and tested no charge. Two separate multimeter tests revealed reverse polarity 12.5 Volts. Any thoughts? Their warranty procedure is a real pain. 2 hours ago, EricJ said: No, it's damaged. Lead-acid batteries won't do this on their own and reverse-charging them damages them. It's no bueno, trash. And not covered by the Concorde Warranty. This will be a difficult conversation with your mechanic. BTW - you seem to be experiencing a lot of electrical problems. You said above "1 New battery placed in aircraft 2 Starter would not turn over. 3 starter removed and failed test sent for warranty repair." Sounds like you had a new starter since you sent it back for "warranty repair". Did your starter kill your previous battery due to excessive starting/current draw to begin this chain of events? - is that why you put in a new Concorde battery? Was your previous starter bad and what did they find wrong with your new starter repaired under warranty? It also raises the question how the new battery got fully discharged to begin with - what was the source of leak? Edited October 30, 2022 by 1980Mooney 1 Quote
David Lloyd Posted October 30, 2022 Report Posted October 30, 2022 If the battery was reverse charged prior to install, a Skytech starter would not energize leading one to think defective starter. Would the master or starter relays even pull in with the wrong polarity? More stuff to keep us awake at night! Quote
Arthur Posted October 30, 2022 Author Report Posted October 30, 2022 3 hours ago, 1980Mooney said: And not covered by the Concorde Warranty. This will be a difficult conversation with your mechanic. BTW - you seem to be experiencing a lot of electrical problems. You said above "1 New battery placed in aircraft 2 Starter would not turn over. 3 starter removed and failed test sent for warranty repair." Sounds like you had a new starter since you sent it back for "warranty repair". Did your starter kill your previous battery due to excessive starting/current draw to begin this chain of events? - is that why you put in a new Concorde battery? Was your previous starter bad and what did they find wrong with your new starter repaired under warranty? It also raises the question how the new battery got fully discharged to begin with - what was the source of leak? The starter was rebuilt in December at engine overhaul The repair on the starter stated found screw attaching the fields to the battery post was loose. The battery exchange was started when another mechanic tested the original battery trying to diagnose the starter problem and said it tested at 56%. I now have the envious task of finding the leak that ran this battery down in 8 days will all switches off. 1 Quote
A64Pilot Posted October 31, 2022 Report Posted October 31, 2022 5 hours ago, Arthur said: The starter was rebuilt in December at engine overhaul The repair on the starter stated found screw attaching the fields to the battery post was loose. The battery exchange was started when another mechanic tested the original battery trying to diagnose the starter problem and said it tested at 56%. I now have the envious task of finding the leak that ran this battery down in 8 days will all switches off. Where is the old, bad battery? perhaps you could use it just for testing, don’t ruin another new battery. I’m not saying fly with it, it’s not Airworthy with a capacity that low, but if it’s a Concorde can’t hurt trying their capacity recovery procedure, I’ve seen it work. https://www.concordebattery.com/component/yendifvideoshare/video/4-deep-discharge-recovery-yes-you-can-resurrect-a-dead-battery.html It won’t open for me, maybe an Ipad thing? ”dark current” is easy to measure, disconnect a battery cable and put the multimeter in series, the multimeter should be fuse protected if the dark current is too high. There is also the Jim Bob method of disconnecting a battery cable then touching it back to the post and look for a spark, there shouldn’t be one of course. If there is, somethings drawing power. I believe though with a Master switch only the interior lights and possibly the clock are powered? Quote
1980Mooney Posted October 31, 2022 Report Posted October 31, 2022 (edited) 1 hour ago, A64Pilot said: ”dark current” is easy to measure, disconnect a battery cable and put the multimeter in series, the multimeter should be fuse protected if the dark current is too high. There is also the Jim Bob method of disconnecting a battery cable then touching it back to the post and look for a spark, there shouldn’t be one of course. If there is, somethings drawing power. I believe though with a Master switch only the interior lights and possibly the clock are powered? Basically correct. There is a fused line running directly from the battery to the headliner lights and to the clock (bypassing the Master Switch). It has a single inline 5 amp fuse located in the tailcone near the battery box. On some early J and K there was an optional memory fuel flow meter totalizer (Aerosonic Floscan) that required power to retain its memory. It had a switch which you turned off during long idle periods. So there could be a third "always hot" wire stuffed in the panel even if the archaic flow scan totalizer meter had been removed. From the K POH BTW - I can't open the Concorde article on recovering a dead battery either Edited October 31, 2022 by 1980Mooney Quote
1980Mooney Posted October 31, 2022 Report Posted October 31, 2022 Check this out - more detail on the old style fuel totalizer draining battery. Quote
Pinecone Posted October 31, 2022 Report Posted October 31, 2022 6 hours ago, 1980Mooney said: On some early J and K there was an optional memory fuel flow meter totalizer (Aerosonic Floscan) that required power to retain its memory. It had a switch which you turned off during long idle periods. My 252 has a Shadin with this same switch. Quote
LANCECASPER Posted October 31, 2022 Report Posted October 31, 2022 4 hours ago, Pinecone said: My 252 has a Shadin with this same switch. I'd bet that if you look through the 337's that the Shadin was put in later in the 90's. K models backs then came with a Hoskins FT101 fuel flow indicator with a memory switch. I've never seen a new Shadin install that had the memory switch - they probably just used the same wiring to put in the Shadin and left the switch. Picture of the Hoskins FT101 (https://3.bp.blogspot.com/_Xmn_7p1x-IM/RqVj58AEnwI/AAAAAAAAAAs/vkbfw2ZGGMw/s1600-h/n5236g+panel.jpg) - Far right just under the MP gauge. Quote
Pinecone Posted October 31, 2022 Report Posted October 31, 2022 Not near the airplane to check. Not sure why I was thinking it was a Shadin. Quote
A64Pilot Posted October 31, 2022 Report Posted October 31, 2022 The capacity recovery procedure is in the MM too https://batterymanagement.concordebattery.com/BatteryDocs/5-0171.pdf In other batteries it’s called “equalization” it is nothing more than an intentional over charge, this can remove some of the sulphation from the plates and sulphation is what cause capacity loss and eventual death in a lead acid battery. Biggest cause of sulphation is a battery sitting at less than full charge, that’s how tenders work, they keep a battery fully charged, greatly slowing sulphation. Article on equalization, good AKA expensive chargers are programmable and an equalization / recovery charge can be programmed. https://batteryuniversity.com/article/bu-404-what-is-equalizing-charge But all you need is a good adjustable power supply, which also comes in handy as an APU for doing avionics work, so it’s not wasted money Quote
Fly Boomer Posted October 31, 2022 Report Posted October 31, 2022 18 hours ago, 1980Mooney said: So there could be a third "always hot" wire stuffed in the panel even if the archaic flow scan totalizer meter had been removed I was looking at my POH, and I see the verbiage you referred to, but I’m not near the airplane right now, so not sure if I have the switch. Was the idea that for an en route fuel stop, you would leave it on, but turn it off at journey’s end? Quote
1980Mooney Posted October 31, 2022 Report Posted October 31, 2022 5 minutes ago, Fly Boomer said: I was looking at my POH, and I see the verbiage you referred to, but I’m not near the airplane right now, so not sure if I have the switch. Was the idea that for an en route fuel stop, you would leave it on, but turn it off at journey’s end? I think that was the idea. I don't know the current draw but I bet you could leave it on for it on for more than a day. Quote
Arthur Posted November 2, 2022 Author Report Posted November 2, 2022 First I’d like to thank everyone for their response. I still haven’t figured out the problem, but I did find a floating switch behind the panel and I have the fuel flow system referred to in some replies. This has been like this since I bought the plane 3 years ago and never had a problem even if I didn’t fly to 2 or 3 weeks. At the present time I have found a 9.Mili amp parasitic drain no matter what I do. All switches off. All breakers off doesn’t change anything. I’m going to try mounting the found switch and remove the dalton clock to see if that changes the draw. Does anyone know what an acceptable parasitic draw would be? Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.