I have two receiver batteries that have not been charged in at least three months and when I plugged one into the duralite charger, the green light came on and started charging, after an hour I turned the switch on and had no power to the recever/servos. I put it back on the charger.

Then after two hours I got power to servos etc and stuff moved via transmitter and then for giggles I stuck my duralite voltmeter on the pack and to my surprise NOTHING. Stuck it back on the charger.

On the other pack I stuck it first on the volt meter and nothing, then stuck it on the charger and the green light blinked a few times (which I've never seen the charger do that before) and then it turned off with no green light indicating charging (blinking stopped somewhere between 5 and 15 minutes, I wasn't looking).

Any ideas what the blinking is for? And is there some voltage that the receiver pack has to reach before the duralite voltmeter will read it?

Thanks,

Sean

Probably a fault but I don't have your equipment so don't take my word for it.

I'm concerned that the packs were dead after 3 months - is that right? This should not happen with Lipo's or Lion's which is what Duralites are. Some of the older ones were tadirans. In any case if the voltage is allowed to get too low they die. These chemistries have excellent charge retention over time - like a % or 2 loss per month. If they are dead after 3 months storage you may have a problem with the way things are wired - there is a current leak somewhere such as having the switch between the regulator and the Rx instead of between the battery and regulator. The regulator would draw some small amount of current even with no load on the output side. Flying and charging every week or two or three might be fine but aft a month or more the pack gets discharged to far.

Again, I don't use this stuff for Rx power. I do know a lot about batteries though - been flying electrics for a long time...

Chris, I hope your wrong, but I'm giving the two receiver packs a good charge all day long. We'll see tonight. Interestingly, the ECU packs for the turbine which would not be connected to a regulator are both in tip top shape. That would seem to support your statement.

That being said, the battery that was blinking on the charger was not connected to anything (it was in a drawer) and I know it was charged when I put it there.

If setting these batteries aside for a few months can cause this problem, I might go back to Nicads as these batteries are too expensive to have them go bad by simply setting an airplane aside for a couple of months.

Hmmmmmmmmmmmm.

Maybe call The good folks at Duralite and ask them? ...........

what would they know? besides if it's posted here it's got to be the truth. LOL

hey Mark just made a pylon for the king. hopefully when I leave Fresno the "fat boyz" will help me bring home a pair of the Snakes!!!

c'ya in a month

buck

It's very important that the regulator is not plugged in between the battery packs and the switch. If it is, the regulator will pull a small current out of the battery until it is dead. If the pack gets below a certain voltage it will be damaged.

The voltage regulator must be installed between the switch and the RX. That way when you turn off the switch the battery pack is isolated.

Hope this helps!

Another tip I picked up on the RCU Battery Forum is that Liths are best stored for long time periods of no use in a partially discharged state......70% is about the best, as opposed to Nicads and Lead Acids that are best stored fully charged.....I did this with my Lith ECU and RX batts in my HS which hasn't flown since Lake Wales, last November.....ran a discharge cycle on them and both are good 9 months later......voltage was down to 7.2 volts with a 1 amp load .......

Don't know how to exactly discharge to 70% without a caibrated scope, but I charge fully, then discharged down to about 7.0 volts with a 1 amp load as a guesstimate.....

I know David Reid had his tranny pack go flat at MAB this year.....don't know what he found out about the pack after he sent it back to Duralite......

Liths are great, but still deserve regular capacity discharge checks for safety.....

Tom

Most regulators have a lot of lekage and will flatten a battery.

[8D]

im wondering if its not your charger. each charger has a chip built into it to regulate the charging. If the chip is going bad its not going to charge the battery to its maxium output no matter how many times you put it on the charger. Try using a different battery charger and see if thats the problem. My kids RC firetruck came with a really cheap charger and i charged the battery as per instructions. Well the truck ran for 30 seconds and the dead battery lite came on. Well to make a long story short. The processing chip or voltage chip was bad and had to buy a different charger..Charged the battery and the thing ran for over an hour on a single charge..havent had any problems with it. Another thing about rechargeable batteries is they can only be recharged a certain number of times before they become dead... Just a sugesstion.

well, after 24 hours on the charger one pack is at 4.08 volts and the other appears to be working. My regulator is wired after the switch as I'd been told about the draining in the regulator when I bought the batteries.

The one that was on the blinking light is the one that appears to be working (with a 1 amp load I'm at 7.5 volts.

That passes my tests here, So I'm gonna fly today and send the other pack in for a check.

Tom, and others, thanks for the input.

Lost a great day of flying yesterday over this. Bummer.