SMC 4000/25C/3.7V single cell Hardcase pack.
11-26-2008, 05:44 PM
#181
I don't think it will be very hard to get them to work. Im down to adding only 40g to the lipo and it is just as fast as it was with the big 4600's.
11-26-2008, 05:49 PM
#182
It might be nice if proper manufacturer reps would post suggestions on this thread related to optimizing their current equipment to this battery configuration. An honest "this won't work", or "this and this will work" would be nice. Who knows their hardware better then themselves? Maybe it would help motivate them to have a real feasible answer for us.
11-26-2008, 05:57 PM
#183
Very good info. I would like to dig deaper into this and make some changes if needed to see if i can even improve over what we have now with our 4 cell packs. Lipo has seemed to really take off in TC and offroad. If it can happen in 1/12th, i would like to find out.
11-26-2008, 06:14 PM
#184
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Like I said, Tekin told me to do it the way I described, so that's what I'll be doing. I would suggest, if a manufacturer says to do it a particular way...probalby good idea to do it that way. I was doing it the way you described until I had that conversation with Jim (tekin prez). And it did act "normal" but though that conversation, I changed the way I was doing it.
Read this,
http://www.teamtekin.com/forums/topic.asp?TOPIC_ID=1642
The thread is in reference to RS use in 1/8 off road, but if you read the 5th paragraph it describes the use of a separate BEC(receiver pack) and what to do with the receiver plug on the RS. Which is the same method in any vehicle where a separate BEC(receiver pack) is used with a Tekin RS. BTW I know who Jim is. I have spoke to him as well.
11-26-2008, 06:35 PM
#186
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I spoke to Tekin about RX packs and the RS and this was what I got from the conversation.
If you don't remove the red wire from the "J" connector on the RS when running a receiver pack what happens is the RS will try to run the whole car, including the motor, off of the receiver pack. On top of this, since the voltage of the receiver pack is higher than either a 4 cell or a 1 cell LiPo, the current will also flow from the receiver pack and try to charge the main battery. These things will drain the receiver pack very quickly. Causing the dumping feeling. I actually had it happen with 4 cell 1/12. I ran the RX pack to get maximum voltage to my receiver, servo, and transponder. When I removed the red wire from the "J" connector the problem went away. Just gotta remember to turn on both switches, the one on the RX pack and the one on the RS.
If you don't remove the red wire from the "J" connector on the RS when running a receiver pack what happens is the RS will try to run the whole car, including the motor, off of the receiver pack. On top of this, since the voltage of the receiver pack is higher than either a 4 cell or a 1 cell LiPo, the current will also flow from the receiver pack and try to charge the main battery. These things will drain the receiver pack very quickly. Causing the dumping feeling. I actually had it happen with 4 cell 1/12. I ran the RX pack to get maximum voltage to my receiver, servo, and transponder. When I removed the red wire from the "J" connector the problem went away. Just gotta remember to turn on both switches, the one on the RX pack and the one on the RS.
11-26-2008, 06:42 PM
#189
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Worked for me in 4 cell. 
Just remember to tape the end off the wire will go live when the switch is on. Questions for ya Danny, how did lowering the capacity on this new LiPo slow down the mod cars? Is this pack a single 4000MaH LiPo or two 2000MaH cells in parallel?
Just remember to tape the end off the wire will go live when the switch is on. Questions for ya Danny, how did lowering the capacity on this new LiPo slow down the mod cars? Is this pack a single 4000MaH LiPo or two 2000MaH cells in parallel?
11-26-2008, 06:43 PM
#190
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11-26-2008, 07:11 PM
#191
Try this, it's a trick used sometimes in modified, for those times when the Rx browns out from voltage dips.
Place a single 1.2v 800mah or similar small cell in series with the red wire from the speed control to the Rx. Charge it as a single cell and when the speedo is turned on it will complete the circuit and put out ~3.7 volts from the internal bec +1.2 from the single cell in series, giving you about 4.9v and only 1 switch. Since there is only the single source connector to the Rx and not another in parrell the ESC will not even know the other cell is there and will not use it to run the motor or charge the battery
Place a single 1.2v 800mah or similar small cell in series with the red wire from the speed control to the Rx. Charge it as a single cell and when the speedo is turned on it will complete the circuit and put out ~3.7 volts from the internal bec +1.2 from the single cell in series, giving you about 4.9v and only 1 switch. Since there is only the single source connector to the Rx and not another in parrell the ESC will not even know the other cell is there and will not use it to run the motor or charge the battery
11-26-2008, 08:00 PM
#192
Worked for me in 4 cell. Just remember to tape the end off the wire will go live when the switch is on. Questions for ya Danny, how did lowering the capacity on this new LiPo slow down the mod cars? Is this pack a single 4000MaH LiPo or two 2000MaH cells in parallel?
Just remember to tape the end off the wire will go live when the switch is on. Questions for ya Danny, how did lowering the capacity on this new LiPo slow down the mod cars? Is this pack a single 4000MaH LiPo or two 2000MaH cells in parallel?It's 2 cells in paralell. We hope by having less capacity that the mod guys won't be able to use 2.5 , 3.5 motors and make runtime. So if they have to use 4.5 and up it will slow them down.
11-26-2008, 09:26 PM
#193
I've seen others refer to using the LOSI micro lipo battery as a receiver pack... I don't want to hijack this thread, but is there a thread with instructions on doing this? Isn't the voltage on this pack high for a receiver pack without an external voltage regulator?
11-26-2008, 10:57 PM
#195
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Putting the mod guys on a short leash, so to speak. 