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Jun 11, 2017, 08:16 AM
Proverbs 12:15
dougbo's Avatar
Bummer, perhaps time for a call to Hobby Services? The price of the OEM replacement battery is quite high so one would expect a quality pack.

Doug B.
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Jun 11, 2017, 10:35 AM
Some.. call him Tim...
Ducati Mechanic's Avatar
Quote:
Originally Posted by dougbo
Bummer, perhaps time for a call to Hobby Services? The price of the OEM replacement battery is quite high so one would expect a quality pack.

Doug B.
It's cycles,balances and works fine if you use a proper charger. I've never had a battery I didn't have to balance. I would think the majority of them will do the same thing if you don't balance it from time to time. The aftermarket life pack I purchased for my other Tx is even worse
Jun 11, 2017, 02:17 PM
S.A.D. member
ivanc's Avatar
Quote:
Originally Posted by Ducati Mechanic
The pack that came with mine is not paired that well. If I charge it three times with the wall charger? it gets out of balance by around .035 The IR is not great. My Groupner charger balances it every time.
If this is 0.035V cell voltage difference then it is negligible.

Ivan
Jun 11, 2017, 04:46 PM
Registered User
HotRod34a's Avatar
I have had my 18SZ for almost a year and a half. and I have never used anything but the wall charger on it. After all of the discussion about the cell imbalance, etc., I decided to check my battery today. It was perfectly balanced. Again, it has never seen my balance charger, nothing but the wall charger. Go figure...
Jun 11, 2017, 05:37 PM
S.A.D. member
ivanc's Avatar
Whoever makes the packs for Futaba obviously uses very well matched cells. You get what you pay for! (can go either way though )

Ivan
Jun 11, 2017, 09:01 PM
"Get off the runway!"
Da Big_G's Avatar
I'll bet the built in charge circuit balance charges the pack.
Jun 11, 2017, 09:12 PM
S.A.D. member
ivanc's Avatar
Quote:
Originally Posted by Da Big_G
I'll bet the built in charge circuit balance charges the pack.
Big G,

You lost the bet - the balancing connector is not hooked to the internal circuit. Only the 2-wire servo type connector is and there's no way to balance a 2-cell pack using only 2 wires.

Ivan
Jun 11, 2017, 10:30 PM
Proverbs 12:15
dougbo's Avatar
Quote:
Originally Posted by Ducati Mechanic
It's cycles,balances and works fine if you use a proper charger. I've never had a battery I didn't have to balance. I would think the majority of them will do the same thing if you don't balance it from time to time. The aftermarket life pack I purchased for my other Tx is even worse
I'm assuming Futaba is matching the cells and not worrying about balancing yet provides a tap for those that want to? Back in the day A123 cells were used and abused by RCers with no balancing.

Doug B.
Jun 12, 2017, 01:40 AM
Bo Edstrom, Sweden
Lets assume one cell in a Futaba 18SZ LiFe battery gets weak and You charge with the standard charger that comes with the 18SZ. The charger "sense" when the LiFe pack has reached voltage for the pack that is considered "full". If one cell in the LiFe pack is weak there is a risk the other cell gets overcharged (to high voltage).
As far as I know LiFe packs are safe in that way that they do not catch fire like LiPo cell can if it gets overcharged (to high voltage).
But in the long run how do one detect if a cell gets weak in the LiFe pack in this situation when not balance charge the pack?
I have used many small 2 cell LiPo packs (for indoor flying) that has no balance connector and it has never been any problem despite the packs lack balance connector but it is more dangerous to charge LiPo without balancing since if one cell get weak the other cell may be overcharged and that cell could catch fire because of that.

Just curious in general about charging LiFe without balancing.
Jun 12, 2017, 02:51 AM
Julian T
I almost returned the pack that came with my 18sz. I first charged using the supplied Futaba charger and then thought I would just check cell balance. I wish I had done so before charging as the cells were wildly out of balance by about 0.2v. I have subsequently only charged with a good balancing charger and the pack has slowly recovered its equilibrium, but I suspect that first charge did nothing for the pack's long term health. Other than that I have been very happy with the tx!

Julian
Jun 12, 2017, 10:03 PM
Proverbs 12:15
dougbo's Avatar
I'm assuming the lack of balance charging technology in the radio is a cost savings thing. Certainly LiFE batteries can be abused without the flames of their LiPo cousins.

The 18mz uses a LiPo and has a built in balance charger so ...

Doug B.
Jun 13, 2017, 12:20 AM
Team Futaba
Silent-AV8R's Avatar
I balance charge mine every couple of months. Never seen more than 0.01 volts difference between cells.
Jun 14, 2017, 08:26 AM
"Get off the runway!"
Da Big_G's Avatar
Quote:
Originally Posted by ivanc
Big G,

You lost the bet - the balancing connector is not hooked to the internal circuit. Only the 2-wire servo type connector is and there's no way to balance a 2-cell pack using only 2 wires.

Ivan
Oh well...lol. I did check the cells last night. Both cells are within .01 volts of each other. Not too shabby after 3 charges using the supplied charger. I'll check it every now and then.
Jun 14, 2017, 02:02 PM
Registered User
Hey guys, finally got around to picking up one of these radios and very pleased with it overall.

I've noticed something that may well be present in a lot of radios and is likely a simple programming function I need to learn, but on this radio it's very obvious and I haven't figured it out quite yet. Seems like servo movement only occurs within about 80% of stick movement - that is, the last 20% or so of stick movement does not affect servo travel. Sound familiar to anyone?

Maybe something with AFR? Figure it's probably something simple or common, but my searching skills are letting me down.
Jun 15, 2017, 03:29 AM
Registered User
Quote:
Originally Posted by Cobra99
Hey guys, finally got around to picking up one of these radios and very pleased with it overall.

I've noticed something that may well be present in a lot of radios and is likely a simple programming function I need to learn, but on this radio it's very obvious and I haven't figured it out quite yet. Seems like servo movement only occurs within about 80% of stick movement - that is, the last 20% or so of stick movement does not affect servo travel. Sound familiar to anyone?

Maybe something with AFR? Figure it's probably something simple or common, but my searching skills are letting me down.
That doesn't sound right, I get servo movement across the full range of stick travel, despite whatever mix or afr I have set , have a look on the monitor screen you can see if the stick travel corresponds to the movement on the screen. Have you tried calibrating the sticks go into to the System menu then to H/W setting where you can calibrate the sticks, page 61 of the manual.

Rob


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