Definitely do not use a 3 cell pack on any Jet Central ECU. I use a 6.6 volt 4600 on the F-15. Ton of starts before a recharge. This combination is a winner for any Jet Central turbine. I have used this battery all summer with fantastic results!

Just for those that don't know, a 6.6 4600 A123 is a 2S2P A123 pack. It's a great way to go, especially if you are running Kero start. The only down side is the pack weighs about 10-12oz's.

Chad

With the modified JetCat ECU you can get four Kero starts and runs easy with a 2300Mah three cell A123, I have not tried to get any more as I have always recharged after four flights, it takes about 10mins to put 90% of the power drained back into the A123's its the last 10% that takes the time to put back in, so you can fly all day with a 10 min re-charge between each four flights.

Mike

Do I understand correctly that any servo made to operate at 6v can handle the 6.6v from a fully charged 2s A123?

Most of the new HD digital servos from JR and Hitec have operated with no problems. I do not have any personal experience with Futaba servos, although I have not heard anyone state they have had problems. I know Futaba has some designated 4.8 volts that can NOT be used.

Chad

Thank you Chad. I was planning to run Hitec:

7955tg
5645mg
645mg

I noticed in some further reading today that Mike Mayberry from Hitec says he only suggests using 2s A123 w/o a regulator on Hitec's coreless servos only. Sounds like the 5645 and 645 are a no go?

.

I have personally used 645's with no problems at all.

Chad

645`s worked fine for me too.
V..

Good to hear. Thank you both.

Just a comment. I have observed that fully charged A123 batteries (2 cell 4600 mah) start out at 7.0 volts then drop back shortly to 6.67 volts.

That's correct. They actually peak at 7.2v fresh off the charge, but drop down to their nominal voltage quickly.

Chad

Ken,
They will stay at 6.6v for a long time...

V..

Can you use the new Triton EQ to charge these A123 packs?

Good information Chad. My reason for mentioning the peak voltage is that if someone has servos that are above the maximum voltage at 6.66 volts then the 7.2 volts might cook them. I am using all Futaba digital servos tied to a Smart Fly power expander in our 42% Super Decathlon and have encountered no problem. Of course, the Smart Fly provides regulated voltage for the receiver. The ailerons are fed through a Futaba MSA-10 equalizer.

Chad,

A couple Noob questions: Iam eventually going to dump the L-ions that I have been flying for the last few years for A123's. I would like to move to the spektrum powersafe rx's to utilize the larger batt leads. Is it possible to run 123's with just one lead coming out (deans or EC3) plug it into the rx leads for power on, unplug for power off and charging (through a single HD lead.... i.e. no balancing?) My other question is have they discontinued the simple Enerland charger that will charge at 8amp unbalanced?

TIA,

Smitty

Big Bird,

Don't sweat the voltage, a 5 cell nimh pack fresh off the charge is about 7 volts too!


Smitty,

Yes, although I would go ahead and get the balancing connector too! I don't know anything about the charger you mentioned. Personally, I use and sell the CellPro Multi-4. IMO it is the best charger on the market, especially for the price.

Chad

Ifound them - not discontinued - have you seen these?<a href="http://www.bphobbies.com/view.asp?id=C2116942&amp;pid=C2320006">

http://www.bphobbies.com/view.asp?id=C2116942&amp;pid=C2320006</a>

Smitty,

I've seen them, but never used them. I'm just not familiar with them to comment. Sorry [&o]

Chad

No worries!

Hey.... so can you use the "dapter" and a Triton Jr to charge the 2 cell A123's? If so, what setting would you use on the triton? nicd?

Smitty,

I don't know if they still sell the Dapter anymore. That was made back when there weren't any A123 chargers out. Now, with the Multi 4, Thunder Power, the new Triton, and many others, I wouldn't mess around with jimmy-riggin' something up to charge these batteries. Get yourself a good A123 charger if you're going to make the switch.

Chad

Thinking about going a123's instead of lith ion for the new flash I am finishing.
I would like a charger that could do 2 batteries at a time. How is the cellpro 10s compared to the multi 4?
OR is there something better out there?
What would be the average time frame for a normal charge?

Pete

Bantam do a dual charger which I have and it charges two 2cell A123's at 10amps if you wish to do this, but Robbe have just brought out a tripple charger which will also do this, personally on the field I use a three small chargers from Flightpower that fit in my flight box if I need to field charge as I find the convenience of being able to put them in the field box outweighs the inconvenience of having to carry yet another box to the field, I only ballance charge when I get the aircraft back to the workshop this seems to be sufficient for A123's.

Mike

Pete,

I would go with 2 Multi 4's over a 10's. Why? The Multi 4's charge everything under the sun, whereas the 10S only charge A123's and Lipos. Not to mention a 10S is about the same price as 2 Multi 4's.

Just my .02. I really believe the Multi 4 is the best charger out, especially for the money. Where they lose their value os for someone looking to charge high cell count lipos at high rates. If you only charge 4S's or less, you can't go wrong.

Chad

Thank I will probally go with the Multi 4.
One question. Say I fully charged went to the field flew 3 flights. About how long would it take to re-charge.

That all accords how much power you have taken out of the packs, I work on about 150Mah per flight and it all accords how much you charge at, all obvious rearly, 500Mah will take half an hour at 1amp, but the beauty of the A123's is you can charge them at way over that if you are in a hurry, I generally charge at 5amps so it takes about 6 mins to put 500Mah back in, just put the charger on the batteries whilst you re-fuel.

Mike