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Old 03-02-2010, 08:04 AM   #1
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Default 1S setups with 2s receiver packs… Bad!

DO NOT USE A 2S LIPO RECEIVER PACK WITH THE TEKIN RS AND RSPRO.

The move to 1s lipo for some race classes was not very well thought out by the manufacturers of the electronics. In fact it was not thought out at all and one day there were just people using 1S, and it worked… sort of.

To make 1S run strong for the entire run the esc’s need a receiver pack or booster to help power the esc brains, receiver and servo. With this extra voltage source we can get full power from the 1S battery for the entire run.

Most users understood that the BEC is a 6V line and the receiver pack or booster should also be around 6V. 5 cell, 2S with a regulator and boosters were common. Recently many have started using a 2s lipo battery with no regulator which supplies 8.4V when fully charged. The circuits are not designed to accept over 8V backwards thru the BEC and it appears this is causing a number of failures.

Normally we would remove the red wire from the esc receiver plug and we would not care what voltage the receiver pack is, but in this case we are leaving the red wire in place so we can use the receiver pack voltage.

We understand using a 2s lipo is convenient, although we are not really in favor of another battery in the car to hassle with. Since this was never an intended setup we are deciding how much longer we will warranty these user caused failures. I cannot speak for our competitors, but it is likely not a good idea with any esc.

We are making some changes in the software that may allow safe use of a 2s lipo as a receiver pack. We are not sure yet since the unit is simply not designed to handle that much voltage in those circuits. Until then we are asking everyone to not use a 2s lipo as a receiver pack with the Tekin RS esc’s unless you have a regulator.

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Old 03-02-2010, 08:17 AM   #2
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i have been using a Life 2s pack with mine with no issue at all they are 6.6v nominal. how do you feel about these being used as reciever pack? they have worked well for me so far.
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Old 03-02-2010, 12:24 PM   #3
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Quote:
Originally Posted by kawirider View Post
i have been using a Life 2s pack with mine with no issue at all they are 6.6v nominal. how do you feel about these being used as reciever pack? they have worked well for me so far.

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Old 03-02-2010, 01:02 PM   #4
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Anybody have a part# for a regulator?

and/or

a LiFe pack with it's own plug-in charger?
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Old 03-02-2010, 01:12 PM   #5
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I'm really getting tired of my 1s setup on my 1/12. Not only all these hassles of running a reciever pack or boosters. But just the inconsistent speeds I get from the begginning of the run to the end of the run. To me there is absolutely no reason why we can't run 2s 7.4v setup now the we have 21.5 and the new 25.5 brushless motors.
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Old 03-02-2010, 01:13 PM   #6
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I'm a battery maker and I've had these very same discussions with people day after day who decide that to save a few $$ they are going to subject 200$+ worth of their electronics to voltages they are not intended to handle.

In my experience, Lipo w/o regulator is bad news for anything but the newest receivers and high voltage servos, even then I really wouldn't recommend it. Lipo with a regulator is o.k. but you MUST keep a close watch on your regulator. These little devices are not indestructable and if they take a hit in the wrong way they can fail, I've seen a bad regulator fry 2x JR 9100 servos in back to back heats.

The Tekin RS has proven to be pretty durable, I've been running mine for more than 2 seasons now with no issues but I don't use Lipo RX packs. I always steer people away from Lipo in a receiver pack because it's just not worth the risk. What exactly are you gaining by using lipo? Use LiFe (Trinity, Muchmore, et al), or a micro NiMh from me or IRS, you get similar MAH they don't take any special charging or maintenance other than what you are already used to and the risks of frying something are almost non-existent.

Jim I'm really happy you brought this up. Lipo's are great but they aren't meant for every application, I use them and they've made my pit bag much lighter but use the right battery for the right application, LiFe or NiMh for receiver and Lipo for powering the motor. Keeps your electronics healthier longer.
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Old 03-02-2010, 01:20 PM   #7
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Quote:
Originally Posted by acyrier View Post
Anybody have a part# for a regulator?

and/or

a LiFe pack with it's own plug-in charger?
http://www.xceedrc.com/product/105002

I've found this to be the smallest lightest most durable 2s regulator. It is NOT fuel proof (it IS resistant not proof) however so put it in a balloon.

http://www.nexusracing.com/product_i...64d096f37d72e7

You can use most modern chargers to charge lifepo4 chemistry.

My 5 cell micro nimh pack
http://www.skyrocketbatteries.com/pr...products_id=92

I can't find a link to the IRS pack but I'll call Dave and ask him for it.
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Old 03-02-2010, 03:13 PM   #8
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Default using 8.4v

Hey, if 6v is ok, how come you can't use 8.4v? You seriously can't expect the r/c community to follow any rules with their equipment, can you?

Anyway, a regulator is $20. Come on, you expect us to spend $20 to protect a $200 esc and an $80 servo. Wow, that is just too expensive!!!

Plus, if I do damage my esc, can I send it back and have you fix it for free?
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Old 03-02-2010, 06:12 PM   #9
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I've had 3 of these baby lipos take a dive on me this year.. I had enough and went back to a 4 cel nimh rec pack 4.8v. End of problems for me anyways. Thanks for the update Jim. Keep up the good work out there..
P.S tell TY to get some work done..
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Old 03-02-2010, 06:51 PM   #10
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Quote:
Originally Posted by TeamTekin View Post
Normally we would remove the red wire from the esc receiver plug and we would not care what voltage the receiver pack is, but in this case we are leaving the red wire in place so we can use the receiver pack voltage.
I'm not clear on this sentence.

I am planning on trying a 1S Lipo system on Wednesday. My intent was to tape the ESC Power Switch in the OFF position and plug a 6 volt 5 cell receiver pack right into the receiver BATT plug.

Will this work OK, or should I be doing something more?

Thanks!
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Old 03-02-2010, 06:52 PM   #11
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The Losi Micro T battery pack works perfectly. And I can still use my old charger.

https://www.ssl-stormerhobbies.com/c...ns&pn=LOSB0848
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Old 03-02-2010, 08:09 PM   #12
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Quote:
Originally Posted by TeamTekin View Post
DO NOT USE A 2S LIPO RECEIVER PACK WITH THE TEKIN RS AND RSPRO.

The move to 1s lipo for some race classes was not very well thought out by the manufacturers of the electronics. In fact it was not thought out at all and one day there were just people using 1S, and it worked… sort of.

To make 1S run strong for the entire run the esc’s need a receiver pack or booster to help power the esc brains, receiver and servo. With this extra voltage source we can get full power from the 1S battery for the entire run.

Most users understood that the BEC is a 6V line and the receiver pack or booster should also be around 6V. 5 cell, 2S with a regulator and boosters were common. Recently many have started using a 2s lipo battery with no regulator which supplies 8.4V when fully charged. The circuits are not designed to accept over 8V backwards thru the BEC and it appears this is causing a number of failures.

Normally we would remove the red wire from the esc receiver plug and we would not care what voltage the receiver pack is, but in this case we are leaving the red wire in place so we can use the receiver pack voltage.

We understand using a 2s lipo is convenient, although we are not really in favor of another battery in the car to hassle with. Since this was never an intended setup we are deciding how much longer we will warranty these user caused failures. I cannot speak for our competitors, but it is likely not a good idea with any esc.

We are making some changes in the software that may allow safe use of a 2s lipo as a receiver pack. We are not sure yet since the unit is simply not designed to handle that much voltage in those circuits. Until then we are asking everyone to not use a 2s lipo as a receiver pack with the Tekin RS esc’s unless you have a regulator.

Tekin Prez
Can this Mini LiFE 6.6V Receiver Battery - 220mah be used? If not Lipo 2s needs to be the norm in all races.

http://www.nexusracing.com/product_i...64d096f37d72e7
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Old 03-02-2010, 08:28 PM   #13
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Quote:
Originally Posted by gonzo416 View Post
Can this Mini LiFE 6.6V Receiver Battery - 220mah be used? If not Lipo 2s needs to be the norm in all races.

http://www.nexusracing.com/product_i...64d096f37d72e7
Jim's post clearly says "2S lipo receiver packs" and that is how I understand it.

I have been using the Trinity/Epic Mini LiFE 6.6V 220mah Receiver Pack with the RS ESC in my WGT for 3 months now. No issues; except, I had to replace the Mickey Mouse on/off switch on it.

Leaves me with max power from 1S to the motor.
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Old 03-02-2010, 08:32 PM   #14
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What is the fully charge voltage of LiFe packs?
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Old 03-02-2010, 08:39 PM   #15
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you charge life packs to 3.6 volts per cell. These would actually be a very ideal pack to run. You would get the same voltage as 4cell nimh pretty much, but they are more robust then lipos. A 2s a123 pack would get you the 10 minute 17.5 heat & weigh in at 150 grams.
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