Myron Beaumont Posted November 9, 2008 Author Share Posted November 9, 2008 Timbo & PhilOne LED on the charger kept flashing 8 minutes longer than the one that remained steady ie not blinking. Have now discharged with a 12V 21 W car bulb (flasher) through the wattage meter .To summarise;It took 5 hrs to go from 8.29V down to 7.7V in 5 hrs connected to Rx & 5 ser vos -Followed by discharging on the bulb for 45 minutes -then checked off load voltage after 5 mins rest to be 6.4 V The battery is now back on the balance charger at 1000mA. Should be "cooked" in about another hour .It's a bit dodgy checking cell voltages off a balance plug isnt it ! Dont like it . Just hope the end voltage has increased slightly again .Fingers crossed .Quite enjoying it all actually ! PS dont know what I'd do without my lipo charge level sheet .Thanks again Timbo & thanks a lot to you all with your suggestions for my resistor .I bet we know the resistance of just about everything in the house ! I know I do.including 'er indoors' hair drier .I must add that ,theoretically ,my bulb doesnt seem to have been a likely candidate but once I'd made a few leads up & adopted the "suck it and see" approach .I just looked at the wattage meter and decided that at a 1.3 A reading was near enough to 1C .Thanks again to you all .f you're interested I'll post the results of the recharge in a while . This must be very boring to ic enthusiasts ! Then again I'm not going off thread (as is usual) now you experts can tell me I've got it all Wrong ! Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted November 9, 2008 Share Posted November 9, 2008 The flashing LED is only indicating balancing action NOT charging.Yes checking potential across those tiny pins of a balance plug needs to be done with care ! Of course the better balancer chargers these days display individual cell voltages on the screendont be afraid to charge at 1C..which should take around an hour or slightly longer. Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted November 9, 2008 Author Share Posted November 9, 2008 I reckon you want me to spend even more money on equipment I'm saving up for a nice big 4st actually & a silencer that is efficient to go with it and---and---and However I do like the idea of the Rx lipo so i dont have to keep switching on & off to conserve power .I suppose the next "must have" is a LED battery indicator on the model ? By the way -I can only charge at 500mA ,1000 mA or 2000mA so exactly 1C is impossible .Its still charging by the way after 1 hr 10 mins --Now I have the job of mixing Xmas cake ingredients for 'er indoors whilst watching all my meters etc ! Quote Link to comment Share on other sites More sharing options...
Former Member Posted November 9, 2008 Share Posted November 9, 2008 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted November 9, 2008 Author Share Posted November 9, 2008 Eric NO She said use brandy & its been mixed with all the fruit overnight HHmm Tastes lovely even raw ! Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted November 9, 2008 Author Share Posted November 9, 2008 PS Am discharging again- Hoping for a good result (I'm talking about my bl---y lipo ) I should know its mAh's Available when I use it .as its being monitored by my new fangled wattmeter whose readings I dont trust (plus or minus 5 to ten percent ;Now where did I put the rum . Quote Link to comment Share on other sites More sharing options...
John Bunting Posted November 12, 2008 Share Posted November 12, 2008 Myron, a very useful high-current variable resistor that I've used for years is just a 1 Kilowatt electric fire element: the wire-wound bar type, about half an inch thick. In normal 240v operation these take about 4 amps, so the resistance is about 60 ohms, but varies a bit with current and temperature. If you can find a large croc. clip, the type with rounded jaws that fits on a car battery terminal, you can clip it onto the bar and move it along to get any resistance you want up to the maximum. Then all you need is a cheap digital multimeter, £5 or less from Maplins, which has a 10 amp current range, adjust the clip to set your discharge current to whatever you want, and off you go. Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted November 12, 2008 Author Share Posted November 12, 2008 John Thanks for tips I do have all the gear & more you mention .I have found a 21W/12V bulb which gives a 1C discharge (near as damn it according to my calcs ) Have run the lipo down & up three times now .All seemed to go well til the last cycle ,the capacity being 1100 mAh -not bad for a "dead" 2s lipo rated at 1345 mAh ! (discharges were run down from 8.25 V (90% charge according to Timbos chart) to 6V off load ie 10 minutes after disconnecting from discharge -in other words I found I had to carefully discharge the last 2 mins to get it right down to the 6 V figure.(about 5V UNDER load) Only concern is that a bead of grey "stuff" appeared on one corner about 3 mm dia which I / she picked off easity Should I do another cycling or not .I must admit I'm a bit p----d off with the whole business .Any tips gratefully received as long as I dont have to waste any more money (Just before I go back to proper engines etc full time) Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted November 12, 2008 Share Posted November 12, 2008 I did say that you would be unlikely to get them back to as new condition, and 1100+ from a 1350 pack is not bad really. I would be a little bothered about the grey matter leaking out - sure its from the Lipo Myron Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted November 12, 2008 Author Share Posted November 12, 2008 Timbo It definately oosed out the lipo. I dont have any grey matter (not where it matters anyway ) Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted November 12, 2008 Share Posted November 12, 2008 I dont think I would like to trust this to a radio set anymore. I would keep it for non critical applications such as lighting and sound effect circuits - also, might fit in the indooor chopper type things. Quote Link to comment Share on other sites More sharing options...
Myron Beaumont Posted November 12, 2008 Author Share Posted November 12, 2008 I'll put it on Swap Shop then Eric might be interested Quote Link to comment Share on other sites More sharing options...
Former Member Posted November 12, 2008 Share Posted November 12, 2008 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
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