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Old 07-11-2008, 02:40 AM   #1
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Default FlightPower - Trackpower Saddle Pack Voltage?



What is the voltage of the individual packs? Are they 7.4V/2 = 3.7V?
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Old 07-11-2008, 02:56 AM   #2
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1 piece of a Trakpower saddle is 3.7 Volt nominal.

the 2 in series then becomes 7.4V.
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Old 07-11-2008, 02:59 AM   #3
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Thanks UK, that's what I figured since this pack is hooked up in series.

I'm considering to buy this for my BJ4WE and for use on my Robot, which uses Hitec HSR5990TG servos. I'm trying to keep the voltage down, below the rated 7.2V.

Do you know of any LiPos that comes in 6.0V nominal? Equivalent to a 5-cell sub-C NiMH? All I see is 7.4V LiPos and 11V LiPos...
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Old 07-11-2008, 03:21 AM   #4
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Quote:
Originally Posted by tom_chang79 View Post
Thanks UK, that's what I figured since this pack is hooked up in series.

I'm considering to buy this for my BJ4WE and for use on my Robot, which uses Hitec HSR5990TG servos. I'm trying to keep the voltage down, below the rated 7.2V.

Do you know of any LiPos that comes in 6.0V nominal? Equivalent to a 5-cell sub-C NiMH? All I see is 7.4V LiPos and 11V LiPos...
5 cell sub-c will peak at over 6.0v but what you could use is a regulator...
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Old 07-11-2008, 05:32 AM   #5
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Thats 7.4 nominal. After a full charge they will be 8.4. So if you're real worried about your electronics you can go one of two routes, either way poke your head in over at the 1/8 scale electric conversion thread because this is about the most common issue they deal with. They have to drop voltages of 5 and 6 cell lipo's down to a useable level, so..
One option is get a new Hitec servo like they're using in those 1/8 scales that is made specifically for high voltage. Option two is get a voltage regulator like was said earlier.
But to be honest with you I have never heard of anyone doing either one of those for 2 cell lipo? I only use Futaba BLS451 servo's and they handle the voltage fine.

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Old 07-11-2008, 06:33 AM   #6
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Use a Switching BEC for bringing down 7V or more to 5.5V or so for radio parts.
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Old 07-11-2008, 07:15 AM   #7
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In the BJ4 your speed control will use it's internal BEC to regulate the proper voltage out to your receiver so it and your servo will have the proper voltage.


As for your robot, If all of your servos are hitec I believe they will handle the voltage straight out of the lipo with no problem. Check with Tony of Tony's Screws on here. He has been doing a lot of "testing" of the hitec servos with a 2 cell lipo in his 1/8th electric stuff. He could tell you if they will handle the voltage or not.
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