Eagletree with A123 Butt saver setup!!!!!!

[Kiwi]

Guys

Thought I would share my findings over the past week setting up my 260 with a DA85 and A123 packs everywhere.

I installed one pack on ignition and its wired to a heavy duty switch directly to the ignition module. No reg, no kill system etc (yet) The whole idea of this build was to keep everything as simple as humanly possible and light as can be.

The plane is an old SD 260 35% ARF. Servos are HITEC 5945's all round. Two each on ailerons, two on rudder and one on each elevator half.

Receiver is a FUTABA 2048 PCM for the 14MZ. Again all the servos are set from the radio. No power system installed at all. Just two A123 2300 MaH packs direct to the receiver. Yes, no switches or anything in the middle. Pop the canopy to turn it on and off. As I had four empty slots in the Rx I made up some heavy duty leads so I feed power to four pin sets in the Rx. Theory says thats good for 12 amps cont. and 28 amps burst. If I use that much I figure I am in deep pooh anyway.

Now all this is temporary but the reason for doing all this was to fly the buggery out of this thing fitted with twin EagleTree data recorders. I purchased two of them off Bill so I could do both packs. That is see voltage, Mah draw per flight etc and also download the inflight data to see what sort of current the setup draws doing all sorts of crazy stuff.

Well the setting up was a learning experience and I feel the information I got should not just be lost on me. I burnt two new servos out setting this thing up and have a new way to setup my planes for A123 systems in the future.

DO NOT THROW THOSE OLD 4.8 VOLT PACKS AWAY!!!!!!!!!!!!!!!!

When I went to gang my rudder servos I set one up, unplugged the other and set it up then fine tuned it so there was no servo fighting. But on my 14MZ when you push the tab to advance the end points it can often go haywire and run away 30 to 40 percent with no warning. Well with a 4.8 volt pack that wont hurt much as the servo stalls, but with a twin A123 system feeding the fire there's no shortage of amperes. It smoked that servo in a flash. I had a spare one out of another plane so I fitted it but !!!!!! it had been programmed with a shorter end point. So when I put that little bugger in and went to set the end points up SMOKE!!!!! again. I was super peeved off by this time. But lesson learned with A123 systems is there is no room for a short circuit or a servo jam up. If your wired direct your going to melt stuff with them.

OK second lesson from the week was how fast these packs turn from working wonders to dead. Doing all this setting up etc over the week took its toll and as there is no easy way to tell how good your pack is you really need some way to see what sort of consumption you have. Well during the setup, many times I might add, I was tinkering away and poof.!!!!! The lights went out. I mean I was adjusting nicely and everything seemed perfect, gave the rudder a twitch and nothing. I mean zero, not a murmur. I unplugged the packs, put a volt meter on them and got 3.2 volts. Thats low enough to turn off the Rx, and it did.

Now its highly likely if I had been flying it there would have been some indication with sluggish servos etc, well I hope so but guys these things just turn off when they are done with.

OK more of the saga, Today I took the old girl out for a test flight. It was windier than a football stadium full of Irishmen after a night on the stout, but still flyable. Everything in the power department on this is new. Batteries, motor etc etc. Plus I had the twin Eagle tree setup.

When I purchased them I also got the little LCD displays and man they are the ducks nuts when it comes to A123 systems I'm sure. I got in two 11 minute flights and each flight used up 200 MaH of juice. Given that I have 2300 available x 2 of which 85% is usable. That works out to about 3600 usable Mah or safely 3 hours flying on a charge Now there's not a snowballs chance in hell that I will ever get that amount of airtime in on any given day. But that little LCD panel and data recorder device to me is worth every durned cent of the $70 they cost. Add $40 for the little panel and you have the best insurance ever as it allows you to see what you have used after each flight. You also get a live readout of pack voltage along with temperature of the motor etc etc. I have the rpm sensor fitted to mine, another $10 but its all worth it to me.

No more guess work on what went on, no more thoughts on just one last flight on a dead pack. Guys I'm sold on Bills devices. They weigh nothing, they give you facts and not opinions.

Now all I need to do is reconfigure my setup to go for a single 4600 MaH pack, I dont see a need for two or reserve if your going directly to a receiver. Two packs in parallel does the same thing and it will let me leave one on board data logger permanently fitted inside the plane. So once again in the future I will access to facts and not fiction.

For $110 bucks guys it the best bucks I have spent in a long time.

[brn2fly]

Kiwi, is the only way to check these batteries with the eagle tree data logger? I don't think trying to remeber how many flight I have flown for the day before I charge a good method. What was the cost of your packs and the data logger?

I have some A123 on the way to do some testing on. My hold up with them is there is no way to sure figure out when they need to be charged. Any information would be helpful. Thanks

[dick hanson]

I bet when that batt quit - you sat there ,blinkin like a frog in a hailstorm-
frozen like a deer in the headlights - anyway - when I was checkin out my servos I watched the litle meter in th eplane -and saw that a couple of blips of extra servo travel (into stalled position ) threw the meter faster than Tom Mix can draw his pistol- - so the cells arre a mixed blessing - and may leave one feeling farmished ( like seeing your mother in law go over a cliff in your new car ).
Personally, I won't have a servo programmer in the shop!- those things are as dangerous as a wife at a stag party --
I do use a little thing from JR called a Matchmaker -and a 4.8 batt- to setup center and throws as I assemble a model
these are truly ,handy as a pocket in a shirt.

[dick hanson]

	Quote: Originally Posted by brn2fly
	Kiwi, is the only way to check these batteries with the eagle tree data logger? I don't think trying to remeber how many flight I have flown for the day before I charge a good method. What was the cost of your packs and the data logger? I have some A123 on the way to do some testing on. My hold up with them is there is no way to sure figure out when they need to be charged. Any information would be helpful. Thanks

One sure fire setup: use a CellPro 4 charger -these show voltage and condition of each cell (balance) - and if you can fill your gas tank and go take a p- , in the meantime, the charger will refill your pack and let you know how many amps you just used . Absolutely the safest check out procedure I have seen
there is NFW a loaded meter will tell you how well these cells are charged.
Why?
The voltage output is very flat until th pack runs dry -even under loads
so forget the old technologies -

[brn2fly]

	Quote: Originally Posted by dick hanson
	One sure fire setup: use a CellPro 4 charger -these show voltage and condition of each cell (balance) - and if you can fill your gas tank and go take a p- , in the meantime, the charger will refill your pack and let you know how many amps you just used . Absolutely the safest check out procedure I have seen there is NFW a loaded meter will tell you how well these cells are charged. Why? The voltage output is very flat until th pack runs dry -even under loads so forget the old technologies -

I was asking Kiwi not you, I have already heard what you have said on the subject. Then I guess th 1000 or 2000 cycles dosen't mean anything. Lets see; I charge every few flights (A123) that means I have to charge 4 times when it took only one charge for my current Li-Ion packs for the same flights. So in effect thay last the same amount of time. No benfit and I have to bring extra equipment to charge the batteries.

[BTerry]

	Quote: Originally Posted by brn2fly
	Kiwi, is the only way to check these batteries with the eagle tree data logger? I don't think trying to remeber how many flight I have flown for the day before I charge a good method. What was the cost of your packs and the data logger?

Andy, I don't know what charger you are using but the Cellpro will calculate the remaining charge in your batteries and is moderately accurate. The beneficial thing is the A123 cells charge so fast we shouldn't be too concerned. Just plug it in after a few flights when taking a leak, talking with your buddy, etc, and it is topped off and ready to go again.

[Edge 540]

AHAHAHA Kiwi
The duck nuts?!? LMAO

[BTerry]

Kiwi, those are truly words of wisdom.

One of the problems with this battery type is they will not roll over and quit under high current loads. This is of course one of their strengths too. They will EASILY burn your electronic gear, break pushrods, or strip gears if the setup isn't correct.

[dick hanson]

	Quote: Originally Posted by brn2fly
	I was asking Kiwi not you, I have already heard what you have said on the subject. Then I guess th 1000 or 2000 cycles dosen't mean anything. Lets see; I charge every few flights (A123) that means I have to charge 4 times when it took only one charge for my current Li-Ion packs for the same flights. So in effect thay last the same amount of time. No benfit and I have to bring extra equipment to charge the batteries.

Apparantly you did not care for that answer --
signed
Quick Study

[wildhare]

	Quote:
	I got in two 11 minute flights and each flight used up 200 MaH of juice. Given that I have 2300 available x 2 of which 85% is usable. That works out to about 3600 usable Mah or safely 3 hours flying on a charge Now there's not a snowballs chance in hell that I will ever get that amount of airtime in on any given day.

OK so I have a question.

How long will you fly in a day? What is the average and maximum time that any of you folks will fly in a day?

If 2 2300mah packs will fly for 3 hours, then 1 pack will safely fly 1 1/2 hours. How many people on here think that they fly more than 1 1/2 hours in a typical flying day. That would be 9 10 minute flights, realistically lets call it 8 flights to allow some time for startup and taxiing.

Anybody out there fly more than 8 flights in a normal day?


TF

[Pale Rider]

[superdh]

brn2fly,
1 "cycle" on a lithium based cell is = to a complete charge/discharge

if you only drain the pack half way, then recharge it that is only 1/2 of a cycle, not 1 cycle, drain it 1/4 of the way then recharge it = 1/4 of a full cycle

this is the same for all lithium based cells, li-ion,li-poly and li-fe

recharge as often as you feel neccesary on all types of lithium cells, it doesn't shorten their lifespan or use up the # of cycles you may get