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Lipo Vs Life RX Batteries

Lipo Vs Life RX Batteries

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Old 03-12-2013, 07:44 PM
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Default Lipo Vs Life RX Batteries

Hey Guys,

I have a Kyosho Mp9 however I still don't know whether to use Lipo or Life rx batteries. I'm just scared that the lipo's volt will go under 3.3 and it'll be dead or even worse. If I run Lipo, how do I run it or should I not care, and also if I should get Life instead??

Thanks
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Old 03-12-2013, 07:45 PM
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run LIPO and use the KO propo switch in LIPO mode.
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Old 03-12-2013, 08:07 PM
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DO NOT USE LIPO MODE( LIPO CUTOFF)

think about this, when your driving not knowing your lipo is about to drop , then lipo cutoff kicks in... whats there to put your throttle back to neutral?(and even some servos gears wont allow a throttle return spring etc to pull back)

you can easily tell when your lipo goes flat as steering becomes slow etc just stop an go get your car.
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Old 03-12-2013, 08:08 PM
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but use lipo... i've just made the switch to lipo an hv servos... totaly worth it
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Old 03-12-2013, 08:10 PM
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Alright, thanks alot guys, I definitely switch to lipo!
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Old 03-12-2013, 08:17 PM
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Somehow the lipo cutoff should be in or talk to the rx so that the servos go into fail safe upon power loss. Maybe some sort of capacitor there or in the servo.
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Old 03-12-2013, 08:37 PM
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I still can't understand how racers let their batteries get that low to ever have to worry about it. I can calculate within 10 minutes when my pack needs to be swapped or charged. Unless you battery is failing there should never be any question how long you can run your car before you need to worry. Here's a little tip: Hitech 7955 servos are not rated for HV so they dont draw HV voltage, however they take HV with no problems at all. I can safely run my car for 1.5 hours on a 2000mah Lipo without even coming close to dipping below the danger line. I have in occasion put a screw through a few wires though.... POOF!
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Old 03-12-2013, 08:48 PM
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Originally Posted by Jaz240 View Post
I still can't understand how racers let their batteries get that low to ever have to worry about it. I can calculate within 10 minutes when my pack needs to be swapped or charged. Unless you battery is failing there should never be any question how long you can run your car before you need to worry. Here's a little tip: Hitech 7955 servos are not rated for HV so they dont draw HV voltage, however they take HV with no problems at all. I can safely run my car for 1.5 hours on a 2000mah Lipo without even coming close to dipping below the danger line. I have in occasion put a screw through a few wires though.... POOF!
I don't disagree with anything you said. I run those servos on lipo and their great. I plugged in a battery backwards and told them how I did it and they fixed them both fo free. But, I did have a battery ejected once leaving my truggy on the lid on the far side of the track running wide open. Another POOF!
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Old 03-12-2013, 09:14 PM
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Originally Posted by Jaz240 View Post
Here's a little tip: Hitech 7955 servos are not rated for HV so they dont draw HV voltage, however they take HV with no problems at all. I can safely run my car for 1.5 hours on a 2000mah Lipo without even coming close to dipping below the danger line.
Never knew that the 7955 can handle lipos. By chance do you know if the 5645 can handle lipo as well.
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Old 03-12-2013, 09:23 PM
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Originally Posted by BlueStreakOne View Post
I don't disagree with anything you said. I run those servos on lipo and their great. I plugged in a battery backwards and told them how I did it and they fixed them both fo free. But, I did have a battery ejected once leaving my truggy on the lid on the far side of the track running wide open. Another POOF!
Hitec has the BEST customer service out there. Someone in the electronics forum said another company did, but when I looked up the other company's warranty policy (as I needed to send a switch in) it was 90 days.

I've had friends send year-old servos into Hitec and they fixed them no questions asked, free of charge. What is funny is that someone posted in the other forum that this other company had "the best warranty service around." Funny at best.

Hitec has fixed an amplifier in one of my servos after about 6 months and even paid for shipping!
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Old 03-12-2013, 09:51 PM
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Originally Posted by Jaz240 View Post
Hitech 7955 servos are not rated for HV so they dont draw HV voltage, however they take HV with no problems at all.
Picky maybe, but that is incorrect. Voltage going through an electrical system is dictated by the supply side, not the consumer. Rest assured the full 7.4V is flowing through the 7955. It's just that it's circuitry can withstand 7.4v without damage.

Only reason i'm pointing that out is so someone else doesn't read it and think that any 6v rated servo will work on lipo because "they're only rated for 6v so will only draw 6v".
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Old 03-12-2013, 10:06 PM
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Originally Posted by mdchris View Post
Picky maybe, but that is incorrect. Voltage going through an electrical system is dictated by the supply side, not the consumer. Rest assured the full 7.4V is flowing through the 7955. It's just that it's circuitry can withstand 7.4v without damage.

Only reason i'm pointing that out is so someone else doesn't read it and think that any 6v rated servo will work on lipo because "they're only rated for 6v so will only draw 6v".
Very good point. High voltage is high voltage. Guys running standard stuff on high voltage should expect less life out of there servos and then, you will need that good customer service to fix you EFF up. If your running lipo, get HV servos and save yourself the grief.
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Old 03-12-2013, 10:09 PM
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Originally Posted by mdchris View Post
Picky maybe, but that is incorrect. Voltage going through an electrical system is dictated by the supply side, not the consumer. Rest assured the full 7.4V is flowing through the 7955. It's just that it's circuitry can withstand 7.4v without damage.

Only reason i'm pointing that out is so someone else doesn't read it and think that any 6v rated servo will work on lipo because "they're only rated for 6v so will only draw 6v".
That's not what I meant but I am by no means an electrical guy nor do I have a clue what I'm talking about in terms of technical data but in laymans terms this is the point I was trying to get across; the 7955 servo may be drawing the same voltage as a HV servo but for some reason unbeknownst to me (that's a great word by the way) it does not seem to drain the battery anywhere near as fast as any HV rated servo on the market. Like I said I have no clue why but do a little test if you run HV and have someone you know who runs 7955's.
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Old 03-12-2013, 10:10 PM
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Also for the record I am going on my forth year of racing with 7955 servos and direct Lipo.
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Old 03-12-2013, 10:34 PM
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For sure Jaz, I wasn't trying to call you out or anything, you're completely correct that the 7955 works just fine on 7.4v as has been proven by many people who run them like that. I've done it as well. I've also run a savox 1268tg on 7.4v as well, although only for probably about 2 or 3 hours of run time, this season it will be a backup but at least it didn't insta-poof

I just wanted to clarify the electrical bit so nobody else who happens to find this in a search later or something misunderstood, if you supply 7.4v then the servo gets 7.4v regardless of it's rating.
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