View Full Version : Lipo + ESC = ..............HELP
TBRC1 07-31-2008, 10:45 PM With the changes going on in the racing world, I am left wondering what ESC's will work woth the new lipo batteries. I am thinking of going this direction with a Tekin 3400 lipo, but I am concerned that a GTB 4 cell is not going to work.
If anyone can fill in the blanks and let me know any info on this it would be great :confused:
pmsimkins 07-31-2008, 11:04 PM Any ESC will be fine. The only thing the 4 cell lacks is a LiPO cutoff. If you simply don't run your car until it dumps there will never be an issue. If you are still concerned you can get an external cutoff for ~$20.
Tommygun43 08-01-2008, 01:05 AM Just curious...what's happens if you do run a LiPo until it dumps? Damage to the battery? Would the pack be unsafe? ruined? or just run flat? (Just wondering)
TBRC1 08-01-2008, 12:36 PM THANKS 20 bucks is waaaaaaaaaaaaay cheaper than getting all new speedos. Now all I need is a check point charger or the lipo upgrade to the GFX and 2 lipo packs.
OH would you happen to know the part number for the external lipo cut off ???? That and is it a Novak product ???
signman501 08-01-2008, 01:21 PM THANKS 20 bucks is waaaaaaaaaaaaay cheaper than getting all new speedos. Now all I need is a check point charger or the lipo upgrade to the GFX and 2 lipo packs.
OH would you happen to know the part number for the external lipo cut off ???? That and is it a Novak product ???
Yes, Novak makes a voltage cutoff. I don't know the number but it's on their website. Why you need two lipos, one for each car? Heck I never take the mine out of the car.
98Ron 08-01-2008, 02:20 PM Her is a link to Novaks cutoff switch
http://www.teamnovak.com/products/lipo_cutoff_module/index.html
TBRC1 08-01-2008, 02:48 PM One for each car .......................one in case of POOF. Never take it out :D man this is going to be great for my lazy racer.
98 thanks for the link.
TBRC1 08-01-2008, 09:52 PM So if I'm looking at a teking 3400 lipo pack whhich lipo cutoff module should I get. It has a 2c charge rate and a 23c discharge rate. If my guess is right it would be the 2c cut off module ???
2c in this case if referring to 2 cells 7.4 volts, it may also have a 2 c charge rate, but that means you can charge at 6.8 amps. Novak makes a 1 cell, a 2 cell and a 3 cell lipo cutoff switch.
swtour 08-04-2008, 01:52 AM Just curious...what's happens if you do run a LiPo until it dumps? Damage to the battery? Would the pack be unsafe? ruined? or just run flat? (Just wondering)
Tommy,
I've been told unreversable damage can occur to the track, and the voltage may stay low/flat. I've also been told that batteries like the ORION can and have been able to sustain this w/o damage in many cases. I've also heard the TEKIN 3400 pack is comprable to the SMC in OUTPUT/PERFORMANCE yet closer to ORION in Durability.
(I haven't run either the Tekin or SMC, nor had any issues w/ the ORION by not using a LIPO cutoff) My son and I's LIPOS are now roughly a year old (or a year in MY possession) I bought ALL but ONE of them used...so WHO KNOWS what kind of abuse they suffered before I got them...
They were both a FLYIN today - man I love this LIPO deal so far...
Better than ROUND CELLS? Nah - probably not...
EASIER than ROUND CELLS? So Far...YES!!!
drdsanders 08-04-2008, 02:25 AM I can't say enough positive things about SMC products and their customer support. I had NIMHs batteries from several companies until I got a SMC. The power far surpassed all other companies NIMHs I had prior. I've emailed them with questions a few times and always got a quick reply. My SMC 28c 5000mah is the only Lipo I've used and I love it so much I'm becoming a walking advertisement them. (FYI..I dont work for SMC nor do I recieve any financial/monetary gain from them)
Just a happy customer
pup1970 08-04-2008, 10:29 AM I have ran a lipo until it dumped once. It ruins the battery and wil not charge back up if you uce an ice charger. DO NOT leave the battery plugged into the esc because it will drain the battery very slowly and ruin it too. I have done both and learned my lesson. If it is possible, get more mah than you will use to be safe. I do not run hard case batteries and have had 0 probelms with damage from wrecks, and I have been in some real hard hits.
nutz4rc 08-04-2008, 01:27 PM If you are racing at a track, check the rules to see if they limit Lipos to certain types (like hard case) or certain brands (like Orion, Peak, SMC). Some tracks don't allow them in certain classes. I have run them in every class I run except Legend (Spec batt req'd) and for over a year have had no trouble. All were used Orion batts. Still in balance even though never used on a balancing charger. Cells are .0001 volt difference according to volt meter so not enough variance to be a concern.
TBRC1 08-05-2008, 07:30 PM AJS I guess this means that the tekin lipo battery would be 2 cells and could be charged the way you said at 6.8. I also guess that teh 2 cell cut off from novak would be the way to go with the tekin pack as well.
Man talk about your new learning curves
badoty 08-05-2008, 11:37 PM I still have a question about that 4 Cell Gtb can it be used with the Lipo or will it over heat the controller with the extra volts??.........:confused:
BRhodes 08-06-2008, 12:02 PM With the changes going on in the racing world, I am left wondering what ESC's will work woth the new lipo batteries. I am thinking of going this direction with a Tekin 3400 lipo, but I am concerned that a GTB 4 cell is not going to work.
If anyone can fill in the blanks and let me know any info on this it would be great :confused:
Toby why the Tekin 3400 over the SMC 3200? Just curious. It seems like some of the big races may put 3200 max for 21.5. Ovalmasters has already done this.
TBRC1 08-06-2008, 10:29 PM Just going with what I was at the Mushroom Bowl a few saturdays ago. Any word on what a limit might be for 13.5 or 17.5 ????
BRhodes 08-06-2008, 11:01 PM Just going with what I was at the Mushroom Bowl a few saturdays ago. Any word on what a limit might be for 13.5 or 17.5 ????
Looks like for Ovalmasters the 17.5 Lipo class will be 5000mah max. Boy do I wish everybody would just agree on something and move forward. I guess that is fantasy land.
swtour 08-06-2008, 11:39 PM There is virtually NO difference in the 4 cell GTB and the 6 cell GTB...most guys run the 6 cell (In Oval) w/ NO Heat Sink or Fan - which is how the 4 cell is offered.
The four cell GTB doesn't have removable esc to receiver wires...
badoty 08-07-2008, 10:50 AM Thanks swtour for that info I thought that might be the case but haven't tried it thinking it would not like the voltage difference........:rolleyes:......
TBRC1 08-07-2008, 11:29 PM MAn this lipo thing is sounding confusing :confused:
swtour 08-07-2008, 11:45 PM what's confusing about it?
Charge it - plug it IN - RACE - recharge - repete
TBRC1 08-08-2008, 10:46 AM It's more the 2c 3c so on and so forth as well as the selection of MHA ratings. I just think NmH was alot easier. Choose a pack by numbers or a matcher you trust and go race. I understand that the lipos are suspossed to be more reliable and longer lasting, but it seems the whole MaH thing is still settling into place.
drdsanders 08-13-2008, 07:55 PM With both lipo and nimh you have cell #'s, and mah's. Some local clubs and ROAR are a little slow to approve various lipos, while other organizations such as the RCProSeries are more progressive. One of the benefits of limitations is that it prevents racers from needing to buy, buy, buy everytime something new comes out.
swtour 08-13-2008, 08:21 PM TBRC1
You have mAh w/ LIPO too, but a 3200 mAh LIPO runs "on track" probably closer to a 4200 NIMH. and a 5000 mAh LIPO runs, and runs and runs....
The 1c, 2c, 3c is pretty easy too..and I'll try to simplify some of it to the best of my ability.
Each lipo pack is made up in cells (Like a NiMh pack is)
With a 4 cell NiMh pack it would be a 4c pack (4 CELL)
a 2c LIPO pack is a 2 cell pack
The difference come in here...
A NiMh CELL is rated at 1.2v per cell
A LIPO CELL is rated at 3.7v per cell
So in order to make a LIPO battery 7.4 volts, you need to CELLS hooked in SERIES (The same way we make voltage w/ NiMh's, using 4 1.2v cells to make 4.8v's)
The Difference comes in in making the Mah ratings you see.
A ORION type 3200 is made up of 2 - 3200 mAh 3.7 cells, hooked in Series to create ONE Pack rated at 7.4 volts, and 3200 mahs. (This is referred to as a 2s1p)
A ORION type 4800 pack is what is known as a 2s2p pack. These packs have (4) 3.7v Cells.
The cells are grouped together in (2) pairs of SERIES packs (to get the 7.4v) then each of those are hooked together in Parallel (to DOUBLE the mAh rating of the cell)
The cells in the ORION 4800 pack are actually 2400 mAh cells, but when you group them in parallel, they become 4800 mAh's.
Confused? It's actually pretty simple...and really not any difference in the old NiMh's except we're using a cell that is about 3 x's the voltage of a NiMh cell. (MAN It would have been cool if they would have been made as 5.0v CELLS instead of 3.7.
One of the benefits of limitations is that it prevents racers from needing to buy, buy, buy everytime something new comes out.
Exactly why we went with Orion 3200's, and while we haven't made rules for '09 yet, and still plan more testing, we're hoping the NEW Orion 3400's will perform REALLY CLOSE to the current legal cell. If they do - we will probably be staying with THOSE for our programs.
TBRC1 08-13-2008, 09:02 PM Sw thanks for the info......................I'll print it out and read it when I have time to really let it sink into the ole brain :D
kevinm 08-14-2008, 07:10 PM .... The 1c, 2c, 3c is pretty easy too..and I'll try to simplify some of it to the best of my ability.
Each lipo pack is made up in cells (Like a NiMh pack is)
With a 4 cell NiMh pack it would be a 4c pack (4 CELL)
a 2c LIPO pack is a 2 cell pack
...
I think you meant to say a 2S lipo is 2-cell, not 2C. The "C" stands for capacity (in amp-hours) and a 2C rating means you can charge it at 2 times it's capacity rating. Most LiPos have a charge rating of 1C, so if it's a 3200mAh then charge it at 3.2 amps. 2C would be up to 6.4 amps charging.
swtour 08-14-2008, 07:24 PM Kevin, CORRECT Thank You
98Ron 08-15-2008, 11:33 AM Back to badoty's question, on GTB 4 cell, Mike Boylan ha a photo on his conference board, of Johnny Bryoles 17.5 car he ran at last weeks oval nats, he has a GTB 4 cell in the car with a SMC 5000 battery. I believe he has been runnning that way all year.
philo 08-16-2008, 09:48 AM I have been running my 4-cell GTB 4-cell in 21-5 lipo without a cutoff switch for several months without any problems.
Phillip
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