fly boy3 Posted March 12, 2012 Share Posted March 12, 2012 Hi all , this w/e I experienced the so called ni -cad "memory syndrome" with my Futaba Tx . Easily solved by cycling same battery. I am told cycling should ony be carried out sparingly. As I may have only 3 /or 4, 10min. flights during a session ,what would be best practice to prevent this occurence again. Should I run battery down low after every flying session. ? Quote Link to comment Share on other sites More sharing options...
John Cole Posted March 12, 2012 Share Posted March 12, 2012 If you have a NiCd in your Tx then it must be old as they have been banned in Eu for several years. So I would advise changing it for a NIMH battery. Old NiCds can fail unexpectedly. NiMH batteries do not suffer from this memory problem. While you are at it I recommend switching to a low-loss one. These do not need charging "the night before you fly". Eneloop is the premium brand but I find Vapex Instant good (and cheap). Buy a made-up pack, of course. Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted March 12, 2012 Share Posted March 12, 2012 Or maybe try one of these....I have had one in my Fuby 10C for about a year & its brilliant....I tend to recharge it after 3 hours (mainly because I can't believe I've not charged the battery after so long) & put around 500mAh back...theoretically I reckon its good for about 9 hours use..... Note you will need to change the plug on the pack to a Fuby one....10 minute job.... Quote Link to comment Share on other sites More sharing options...
John Cole Posted March 12, 2012 Share Posted March 12, 2012 VAPEX packs have the correct plug and are £12.50 post free. They are higher capacity that the Zippy LiFePO4 packs (2500 vs 1800) and retain their charge well enough for me to charge AFTER flying not before. See the link below. Make sure you look up the details for the GREEN NiMH+ pack, not the RED NiMH pack. The red ones have higher capacity but are not low-loss. I use packs from VapexTech both in my Tx and for ALL my Rx packs. Vapex Batteries Edited to correct link.... Edited By Steve Hargreaves - Moderator on 12/03/2012 17:11:01 Quote Link to comment Share on other sites More sharing options...
Seamus O'Leprosy Posted March 12, 2012 Share Posted March 12, 2012 John has broken the Internet Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted March 12, 2012 Share Posted March 12, 2012 Steve has fixed it again..... John...please take a look here......adding URLs to a post can distort the pages for others... Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted March 12, 2012 Share Posted March 12, 2012 John wrote If you have a NiCd in your Tx then it must be old as they have been banned in Eu for several years. Not necessarily - Ripmax/Futaba were supplying new transmitters with NiCds up untill a couple of years ago. A new NiCd should last indefinitely in its storage condition and good quality ones can last for decades. Certainly not always the case for NiMHs... I will admit to using an Eneloop pack in my transmitter where I believe it is adequate for the relatively low current drain. Edited By Martin Harris on 12/03/2012 17:22:03 Quote Link to comment Share on other sites More sharing options...
John Cole Posted March 12, 2012 Share Posted March 12, 2012 Steve: Thanks for fixing. But... I used the link-insert process, as I have always done. Just click on the link-insert button and paste the URL in the box. If a long displayed-text messes up the display, why does the link-insert code not truncate it? Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted March 12, 2012 Share Posted March 12, 2012 H'mmm...not sure John....you need to highlight the text you want to use as the link & then click on the link button & paste the link.....I guess without any highlighted text to attach the URL to it will just paste the URL as it is...... Quote Link to comment Share on other sites More sharing options...
Peter Beeney Posted March 12, 2012 Share Posted March 12, 2012 I’m not quite sure about nicads being banned, you can still buy them quite legally. Or I presume legally, they are definitely sold by one reputable company, and I think by some others. flyboy 3, can I ask you how you managed to get your batteries to develop a memory? I’ve tried a few times, once in a fairly serious manner, and I’ve never been able to get anything like a memory effect. In fact, almost an opposite sort of result. This was under carefully controlled conditions with accurate monitoring; and they were the standard sintered type, AA size. And may I ask how you recognised it as a memory effect, rather than perhaps the charger just not recognising the state of charge of the pack? I only ask because I’ve been given cells that have been suffering from memory effect and in every case it was something else. One classic example of a new rx pack for a helicopter was black wire corrosion; a quick re-wire and it was soon back in action. Think I could do with some memory effect now, mine seems to be disappearing fast these days…… PB Quote Link to comment Share on other sites More sharing options...
John Cole Posted March 12, 2012 Share Posted March 12, 2012 Apart from some specialised uses, the import or manufacture of NiCd cells in the UK is banned under the Eu Batteries Directive of 2006, as implemented in UK law in 2009. Quote Link to comment Share on other sites More sharing options...
John Cole Posted March 12, 2012 Share Posted March 12, 2012 Steve: I entered the text of my comment, and then I clicked the button to insert a link. I then pasted the link into the box, and clicked OK. That's what you do on all Forum-type sites. If that doesn't work then blame the guy who wrote the script that is behind the link-button. Don't blame the user! If "it will just paste the URL as it is......" and that doesn't work correctly on this website, then that's an exception-condition the programmer should have handled. If the guy worked for me he would have fixed it. If the guy failed to fix it, he would no longer be working for me. Quote Link to comment Share on other sites More sharing options...
fly boy3 Posted March 12, 2012 Author Share Posted March 12, 2012 Hi Peter, I think it went like this, Charge up, bad weather, no flights, this went on for a week or so. Being a bit lazy did not check with v/tester first. Charged up flew one flight , then rain. 2 days later charged up. flew 3 mins. than Tx alarm went of f. 8.5volts. Landed safely. Charged up once again, then put it on discharge. At the end of cycle, battery was charged up to 10.1 volts. Left Tx on to see how long charge would last . Nearly 2 hours elapsed before low volt alarm sounded at 8.5volts. I assumed this was so called "memory effect". Could be well off the mark Peter. Cheers Quote Link to comment Share on other sites More sharing options...
fly boy3 Posted March 12, 2012 Author Share Posted March 12, 2012 Hi John, thanks again for the info re Vapex. NiMH's are the way forward for me, as it is quite possible I will not be able to buy Nicads any more, re Johns post. There again, Lipos are one step ahead also. Thanks all for your help. Quote Link to comment Share on other sites More sharing options...
Peter Beeney Posted March 12, 2012 Share Posted March 12, 2012 fly boy 3, thanks for the reply. I’m certainly not convinced that what you describe is a memory effect. As I’ve understood this from way back, this ‘memory’ account arose from the use of nicads in the early telecommunications satellites, these were doing many charge/discharge cycles, all of exactly the same duration and in low temperatures. After a long time it was found that the cells ‘remembered’ this level and wouldn’t perform beyond this; and although they worked well within these limits they were reluctant to recover their full capacity, too. In very general terms, I’d have thought that 2 hours is not very long for your tx pack to last. Whenever I’ve had any dealings with transmitters the capacity always seems to be at least about 4 hours, or more, but of course your’s may be different. I’d be inclined to have a careful look at all this, is it possible you can do a capacity check? I’m very much guessing here, but if your battery is say 700 mAh then for two hours that’s saying that the current consumption rate is around 350 mA, I’d say that is a bit unusual, in the sense that it seems pretty high. If the pack appears flat, say at 8.5V, then see how much goes in to take it to fully charged, if it’s anything much less than the capacity of the pack then you might have a problem. Anyway, at least with a low volt alarm on the tx you should be able to land before it stops transmitting, but in some cases that can be a bit quick so you don’t want to go there to often! Good Luck with it. PB Quote Link to comment Share on other sites More sharing options...
PatMc Posted March 12, 2012 Share Posted March 12, 2012 I'd just look on it as a battery good for 2 hours solid Tx time. If the capacity is a lot less than that stated it doesn't really matter. Quote Link to comment Share on other sites More sharing options...
ZigZag Posted March 12, 2012 Share Posted March 12, 2012 Regular cycling and deep discharging would appear not to be good for any battery according to this view: www.dansdata.com/gz011.htm I am inclined to agree. Back in the good old, bad old days of nickel cadmium flight power I regularly cycled flight packs to avoid "memory effect". The cycling did nothing for the performance or life of the cells and I frequently experienced cell polarity reversal in packs of NiCD cells. Typically the pack would not last a summer season without one or two cells dying Interestingly, I have two JR X-388 TXs that came standard with 600 mAh NiCD packs back in, I think, 1993 or 1994. They're getting on for 20 years old and both NiCD packs still work well. I have replaced one pack in my field/power flying TX purely for more flying time (with Vapex Instant pack as suggested above) but still using original NiCD in my gliding TX. The packs have not been cycled and are never completely flattened - both TXs have low battery warning set at 9.3V - and are never charged at more than 0.1C. So, I subscribe to the old idea that being gentle with rechargeable batteries, regardless of the chemistry, pays greater dividends than cycling packs . Edited By ZigZag on 12/03/2012 22:54:26 Edited By ZigZag on 12/03/2012 22:55:11 Quote Link to comment Share on other sites More sharing options...
PatMc Posted March 12, 2012 Share Posted March 12, 2012 I always recharge Tx batteries to a delta peak at about 800mA - 1A (any more isn't good for the wiring) IMO cycling using a charger is pointless. If I want to know how long a battery will last I leave it switched on within earshot whilst I'm watching tele or whatever then see how long it takes before the LVA sounds. Quote Link to comment Share on other sites More sharing options...
fly boy3 Posted March 13, 2012 Author Share Posted March 13, 2012 Hi all , thanks for the interest. For Peter, you are correct it is a 700 mah batt. I only have an overnight type charger ( 70ma) , so there is no problem with fast charging,as Zig Zag says be gentle. LoL like Pat's suggestion of just listening for lv alarm to give some idea of transmitting time. Cheers. I probably will have to bite the bullet ,and buy new NiMH for peace of mind. Cheers Quote Link to comment Share on other sites More sharing options...
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