milotron Posted March 21, 2018 Report Posted March 21, 2018 So, I have now joined the club of those illustrious few who have drained their batteries by leaving the cabin lights on. Went out today for a CPL lesson and found it dead to the world. Battery volts down to 1.8v once i opened it up. Looked around and found the little cabin light at the back in the 'Dim' position. I never use them, so I never check them for being off but i must have bumped it with baggage from the trip to Port Hardy last week. Add something else to the 'put the plane to bed' list. i was a little surprised to see a Concorde sealed battery in there, dated from 2014. I suppose that is a reasonable lifespan. I know my AME suggested it was due for replacement next year. After an overnight charging attempt, it is showing only 8 volts. I know these glass mat batteries really don't like a deep discharge, so not totally surprised by this. I have a new Concorde coming in from Spruce, so hopefully can get back up and running for the rest of spring break. So, after dealing with some other charging issues that were likely hard on the previous battery, ( broken alternator battery lead, bad voltage regulator on Alt #2 ), and knowing these batteries are a little more sensitive to charging voltages, here is the question: Do any of you change your regulators to summer/winter voltage settings based on operating temperatures? Quote
Hank Posted March 21, 2018 Report Posted March 21, 2018 I've never touched my regulator. Concord #1 went in Fall '10, replaced Fall '16 since it was cranking slowly and I was headed into the boonies. Otherwise I'd have waited a little longer. Quote
RobertGary1 Posted March 21, 2018 Report Posted March 21, 2018 (edited) Make sure to buy the sealed battery and not the one you add acid to. The local shops like to carry the flood batteries you add acid to because they have a longer shelf life before selling but the selled glass mat battteries last far longer. -Robert Edited March 21, 2018 by RobertGary1 Quote
milotron Posted March 21, 2018 Author Report Posted March 21, 2018 Thanks, I ordered another Concorde RG 35 AXC from aircraft spruce to replace the one that was installed. I can wait a couple of days for it. I'll try again with a different charging technique to get it up to voltage again, but I am planning a cross country trip for the summer and don't want to have to worry about the battery condition grounding me. iain 1 Quote
DonMuncy Posted March 21, 2018 Report Posted March 21, 2018 As I have posted before, I developed a timer that an A&P or reasonably proficient hangar elf can easily install, that will absolutely prevent a cabin or luggage light from running a battery down. It keeps the light(s) on for 10 to 12 minutes after the master is turned off. I will share the circuit diagram or I can build you one for $30. (Sorry, it won't keep you from leaving the master on ) 2 Quote
milotron Posted March 21, 2018 Author Report Posted March 21, 2018 Thanks Don. I was thinking of the exact same thing! That or some other indicator, or red marks on the switches that are only visible in the 'on' mode. iain Quote
skydvrboy Posted March 21, 2018 Report Posted March 21, 2018 I was taught to leave the beacon on at all times for this reason. When you walk away, that flashing light reminds you that the master switch is still on. It has saved my butt a time or two. 2 Quote
milotron Posted March 21, 2018 Author Report Posted March 21, 2018 That is a good idea. Unfortunately the cabin lights are operational regardless the position of the master switch. I would have to be deaf to leave my master on for the number of fans/gyros etc screaming away. iain Quote
jaylw314 Posted March 21, 2018 Report Posted March 21, 2018 2 hours ago, milotron said: So, after dealing with some other charging issues that were likely hard on the previous battery, ( broken alternator battery lead, bad voltage regulator on Alt #2 ), and knowing these batteries are a little more sensitive to charging voltages, here is the question: Do any of you change your regulators to summer/winter voltage settings based on operating temperatures? I don't think it's worth adjusting. If you have your regulator at the lower summer voltage, it will still charge the battery to 90% or more during the winter during flight. Then just use a battery charger to get it to 100% once every month or two (or leave it on a float charger all year). Having an AGM battery at 90% isn't going to cause problems in the short term, and you'd much rather ensure they don't get overcharged during a long flight. And while starting the plane might take a lot of current, the total charge used is very small, since you only crank for 5-10 seconds. Quote
Mark89114 Posted March 21, 2018 Report Posted March 21, 2018 36 minutes ago, milotron said: That is a good idea. Unfortunately the cabin lights are operational regardless the position of the master switch. I would have to be deaf to leave my master on for the number of fans/gyros etc screaming away. iain Ha!!! I used to have a turn coordinator that sounded like a garbage disposal....just replaced it, now i am not even sure it is working it is so quiet. Quote
FBCK Posted March 21, 2018 Report Posted March 21, 2018 You should invest in a battery minder charger that is specific to you battery as well. 1 Quote
skydvrboy Posted March 21, 2018 Report Posted March 21, 2018 3 hours ago, milotron said: That is a good idea. Unfortunately the cabin lights are operational regardless the position of the master switch. I would have to be deaf to leave my master on for the number of fans/gyros etc screaming away. iain I see. My master switch kills everything. As much as I fly at night, I can see how that would be handy though. I always wear a headlight so I can still see to get stuff out of the plane after the master is killed. Quote
jaylw314 Posted March 21, 2018 Report Posted March 21, 2018 (edited) 2 minutes ago, skydvrboy said: I see. My master switch kills everything. As much as I fly at night, I can see how that would be handy though. I always wear a headlight so I can still see to get stuff out of the plane after the master is killed. I discovered the previous owner had disconnected the cabin lights entirely. Really the only thing they missed on the pre-purchase inspection that I've found. You could, of course, semi-illegally replace the cabin light bulbs with LED's. I forget the bulb size, but they are common in automotive lighting. Then your battery would survive longer with the lights left on... Edited March 21, 2018 by jaylw314 Quote
milotron Posted March 21, 2018 Author Report Posted March 21, 2018 Looking at the schematics now, it looks like the cabin lights, clock and OEM fuel flow memory is connected direct to the battery, but isolated using the 'fuel mem' switch, if you have one. i looked at the Shadin miniflo manual and it has non-volatile memory not requiring constant power. Since I also do not have the clock, it looks like i can use t his switch as an override to shutdown these lights completely. I don't want to make this $600 mistake again. Battery is starting to come back up, but i don' trust it now. Once it is up to 12v again, I'll do a load test and see how it does. I am not expecting much from it at this point. Getting it down less than 2V is a pretty deep discharge. iain 1 Quote
Guitarmaster Posted March 21, 2018 Report Posted March 21, 2018 As I have posted before, I developed a timer that an A&P or reasonably proficient hangar elf can easily install, that will absolutely prevent a cabin or luggage light from running a battery down. It keeps the light(s) on for 10 to 12 minutes after the master is turned off. I will share the circuit diagram or I can build you one for $30. (Sorry, it won't keep you from leaving the master on ) Could I get a copy of the circuit?Sent from my XT1585 using Tapatalk Quote
DonMuncy Posted March 21, 2018 Report Posted March 21, 2018 41 minutes ago, Guitarmaster said: Could I get a copy of the circuit? Sent from my XT1585 using Tapatalk I can't get it to attach here. If you will PM me your email address, I will send it to you. Quote
Guitarmaster Posted March 21, 2018 Report Posted March 21, 2018 I can't get it to attach here. If you will PM me your email address, I will send it to you. Sent. Sent from my XT1585 using Tapatalk Quote
mooniac15u Posted March 22, 2018 Report Posted March 22, 2018 4 hours ago, milotron said: Looking at the schematics now, it looks like the cabin lights, clock and OEM fuel flow memory is connected direct to the battery, but isolated using the 'fuel mem' switch, if you have one. i looked at the Shadin miniflo manual and it has non-volatile memory not requiring constant power. Since I also do not have the clock, it looks like i can use t his switch as an override to shutdown these lights completely. I don't want to make this $600 mistake again. Battery is starting to come back up, but i don' trust it now. Once it is up to 12v again, I'll do a load test and see how it does. I am not expecting much from it at this point. Getting it down less than 2V is a pretty deep discharge. iain You don't have a clock at all or you don't have one that needs constant power? Quote
Steve W Posted March 22, 2018 Report Posted March 22, 2018 If it's down at 8v it might not recover, but the Concorde ICA manual on their batteries has a procedure that may resolve it for batteries that fail the capacity test. I thought mine was having issues and was going to do the capacity test and possible recovery procedure(in conjunction with my A&P) since I have the gear needed... but then I broke the plane so I don't have to worry about the battery for a while. Quote
milotron Posted March 22, 2018 Author Report Posted March 22, 2018 46 minutes ago, mooniac15u said: You don't have a clock at all or you don't have one that needs constant power? No clock at all. This was a discussion on another thread also.....Someone replaced the clock with an EDM 700 many moons ago. I do need/want to put one in later this year. The one I am considering has a built in backup battery. iain Quote
milotron Posted March 22, 2018 Author Report Posted March 22, 2018 23 minutes ago, Steve W said: If it's down at 8v it might not recover, but the Concorde ICA manual on their batteries has a procedure that may resolve it for batteries that fail the capacity test. I thought mine was having issues and was going to do the capacity test and possible recovery procedure(in conjunction with my A&P) since I have the gear needed... but then I broke the plane so I don't have to worry about the battery for a while. I goosed it back up to 11.45V using another battery on the charger to get the charger working again. I just pulled it off an hour ago. Will see what the stabilized voltage is in the morning, but it is not looking good. I learned a whole lot about charging AGM batteries this morning and used some ad hoc methods to replicate the fancier charging procedures. New one will be here on Friday; I'll use the old with a PV panel, inverter and charge controller for a camera power supply in the yard. iain Quote
Piloto Posted March 22, 2018 Report Posted March 22, 2018 The problem with the cabin lights is that they are connected directly to the battery bypassing the master switch. I connected mine to the stall warning buzzer +line at the front ceiling switch. This only allows the lights to be turned on when the master is on. José Quote
carusoam Posted March 22, 2018 Report Posted March 22, 2018 The battery Minder might do a good job of bringing the battery back to life... But, it may have gotten damaged by the deep discharge... the damage would be noticeable by the battery load test.... It charges up and passes the load test that would be a Concorde miracle! The killer of my batteries has been the name on the side of the battery... and any portable device left plugged in the cigarette lighter socket. interior lights left on will drain an early O’s battery, as will all the memories of the avionics, clock, fuel totalizer, radio frequencies, JPI memory?.... Pp Thinking out loud... best regards, -a- Quote
N231BN Posted March 22, 2018 Report Posted March 22, 2018 An 8-amp battery minder will overcharge a dead battery, hence the minimum voltage for charging. With a dead Concorde, the slower you can charge it the better. It will still boil off and lose water, you just can't add it back like a Gill(actually you can, just not approved by Concorde).A typical sign of an overcharged Concorde is one with the sides "sucked" in. It gets hot and allows gas to escape as the pressure rises then seals up when it cools down. Quote
N201MKTurbo Posted March 22, 2018 Report Posted March 22, 2018 It doesn't boil off the water. The chemical reaction produces an excess of hydrogen. The battery has a safety vent to release the hydrogen if the pressure gets to high. When you over charge it you lose some hydrogen. When the charge state tries to get back in balance there isn't enough hydrogen and it sucks the sides in. Water isn't what it is lacking, it is hydrogen. That's why they are called recombinant gas batteries. http://www.tms.org/pubs/journals/JOM/0101/Nelson-0101.html Quote
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