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View Full Version : ATTENTION LIPO PACKS


Loheswaran
21-12-2012, 12:06 AM
Dear all!!!!!!!!!!!!!!!!!!

BE WARY OF USING LIPO PACKS AS REPLACEMENTS FOR NIHM PACKS!!!!!!!!!!!!

I HAVE HAD THE MISFORTUNE OF BLOWING SOME IC'S IN MY TRANSMITTER RECENTLY, AND HAVE NOW HAD TO MISS A FEW RACE MEETINGS THAT I WAS REALLY LOOKING FORWARD TO:cry::cry::cry:

The problem is that on full charge the voltage can easily overload and blow a circuit.

take care

bigred5765
21-12-2012, 12:59 AM
the voltage a full charge lipo should if charged properly be below that of a set of nimh's/nicads battery pack and shouldn't be a problem, what happened and how did it happen

tomtom
21-12-2012, 01:12 AM
I asked someone at KO when I bought RClazy lipo for my Esprit III and he told me not to fully charge it so I stop the charging at around 4.00/4.10 for each cells.
I noticed the module was hot when fully charged so yes it is safer not to fully charge a lipo for a transmitter, you don't want to burn that one !

bigred5765
21-12-2012, 01:18 AM
crazy but good to know

mattr
21-12-2012, 07:34 AM
Use a LiFe instead.
6.6v fully charged, not 8.4v.
(and cheap as chips)

Loheswaran
21-12-2012, 07:43 AM
I will admit that i am an architect of my own downfall- although the shop i bought from gave some truly idiotic advice.

I wanted to go lipo and asked the uk based shop where I got my radio from if he sold such an item. He said 'no - ur better of going onto ebay'. So i did just that and looked for a tx lipo for my ko ex 10 helios.

I simply balanced charged the damn thing as i could any lipo. I then plugged it on - no whizz no pop - simply drove up 80 miles to silverstone having got up at 5.30 - hey presto - no radio :cry:

I writing this coz o don't want anyone else to have the same experience.

DCM
21-12-2012, 07:48 AM
I run LiPo in my Futaba 3VC for the last 2 years without one issue, balance charged it is only 0.6v more than 8 AA dry cells, I would assume that the voltage is regulated within the radio.

mark christopher
21-12-2012, 08:54 AM
Use a LiFe instead.
6.6v fully charged, not 8.4v.
(and cheap as chips)
????? Cracking sugestion when the low voltage cut off on ko is 9 volts... You use a 3s in ko transmitters.

mark christopher
21-12-2012, 08:56 AM
Same as dcm but over 3 years in a ko Helios running spektrum. Not one problem, but allways been balance charged.

Lonestar
21-12-2012, 09:05 AM
Been using a $9.99 3S lipo pack in my helios for, what, 5 years now??? the same pack, I mean...

Fully charged is 3x4.2V=12.6V (Reality is more like 3x4.12V or so)... 8 brand spanking new alcalines is even more voltage.

Lipos don't kill radios... People do.

Paul

jasond43
21-12-2012, 09:39 AM
been using a 3s in my ko es3 goes to 12.1v on tranny when fully charged been running my lipo for about 3 years now and no probs i have a 3s 2200mah must of had a faulty tranny as 8 1.5 AA's are 12v prob more when new like all nimah's and fully charged lipo's

mattr
21-12-2012, 09:54 AM
????? Cracking sugestion when the low voltage cut off on ko is 9 volts... You use a 3s in ko transmitters.Could just use a 3s LiFe then, 9.9v As opposed to a 3s LiPo with 12.6v.
Mine (2s/1600mAh in a Spektrum) took about 10 to 12 visits to the track to drop from 6.6v to 6v.

Loheswaran
21-12-2012, 10:45 AM
Been using a $9.99 3S lipo pack in my helios for, what, 5 years now??? the same pack, I mean...

Fully charged is 3x4.2V=12.6V (Reality is more like 3x4.12V or so)... 8 brand spanking new alcalines is even more voltage.

Lipos don't kill radios... People do.

Paul

I was told by my radio repairer Mike Ripley that the problem was the LIPO - I assume he knows what he is doing as SMD use his services.

knighthawk
21-12-2012, 10:58 AM
I been running Lipo 3s 2200mah in our four Futaba Transmitters for years
My sons 2 x Futaba 3VC and my Futaba 3VCS and Futaba 3PKS
I personally have never had a problem, as above when balanced my packs show 12.6v and run around 12.2v for a month, I then normally re-balance charge when the voltage drops below 10.5v.

I have heard of this issue from reading a couple other forums

You could try this to solve the over voltage issue

http://www.ebay.co.uk/itm/3s-Lipo-Step-Down-Voltage-Regulator-Radio-TX-Transmitter-Futaba-Hitec-/220865616114

Chequered Flag Racing
21-12-2012, 11:14 AM
Mine (2s/1600mAh in a Spektrum) took about 10 to 12 visits to the track to drop from 6.6v to 6v.

Is this in a DX3s which is four cell nimh?

Link to battery if it is please

mattr
21-12-2012, 12:00 PM
Is this in a DX3s which is four cell nimh?

Link to battery if it is pleaseDX3C, unfortunately, i've recently sold the Tx, and I got the battery from someone else in the first place (OneKiwi). So don't have the specs to hand :confused:
I'll see what i can dig out.

cigbunt
21-12-2012, 12:04 PM
its ott using lipo in a tx, NiCad last months anyways and they dont blow up!
wouldn't advise it unless you know what your doing

metalmickey0
21-12-2012, 12:41 PM
its ott using lipo in a tx, NiCad last months
I agree as been using NiHms in mine for ages and they last for months before even thinking of recharging them.

Northy
21-12-2012, 12:57 PM
You could try this to solve the over voltage issue

http://www.ebay.co.uk/itm/3s-Lipo-Step-Down-Voltage-Regulator-Radio-TX-Transmitter-Futaba-Hitec-/220865616114

Haha, love it, $10 for a big diode :lol:

fidspeed
22-12-2012, 06:56 AM
if its in a ko i have always had to reverse pins in the plug so that the live pin is the pin to the right not the centre as you plug it in to the radio this puts the negative is in the centre

most lipo packs with RX type plugs come with centre pin live this may have caused your failure if you were unaware

no intention of trying to be clever just a possible explanation

i have 5 ko helios currently all lipo 3s powered never had a problem

also if you switch on with aerial down (40 mhz) the tx module will get hot

if i remember correctly a long while ago in the good old days i knew of people who linked in a extra 9th cell to get extra oomph of tx power

regards fid

CrashBangWallop
23-12-2012, 05:36 PM
if i remember correctly a long while ago in the good old days i knew of people who linked in a extra 9th cell to get extra oomph of tx power

regards fid

Guilty, 'as charged' on the 9th cell !

I swapped from using Ni-Mh to Li-po about two years ago in a Futaba 3VCS as I was fed up of having to charge TX packs every other week.
Using 2200Mah Li-Po's with no trouble and they last for about 2 months before they need charging again.

knighthawk
23-12-2012, 05:59 PM
Haha, love it, $10 for a big diode :lol:

It's a option and you could easily make one yourself I'm sure or find a cheaper alternative,

but I think the main point here is that many many racers use lipo in their TX and don't have issue's, maybe there was another problem, not the power source