higher voltage electronics and servos

[jay2006]

can anyone give me a little insight and knowledge on some electronic questions? i recently upgraded the servos in one of my nitro trucks. i upgraded the steering servos to dual spektrum S601H high voltage servos rated at 7.4volts, and i installed 2 spektrum S6170 digital servos for throttle and reverse/forward shift. (that ones rated at 6.0volts) I'm looking at upgrading my receiver babttery pack to either LiPo or LIFE battery. my question is...will that S6170 servo handle 7.4volts from a LiPo recaiver pack? or maybe even a 6.6volt LIFE receiver pack? or will i need to buy a regulator? i know my steering servos will handle the 7.4volts no issues. one would think that a 6volt servo would be okay with a 6.6LIFE battery pack. of course that 6.6 volts is more like 7.2 volts fully charged. so IDK thanks guys

 

[Jam Racing 1]

you are aware that most receivers are designed to use 6.0 volts so you will need a regulator to keep your system alive.....

 

[bifftit]

I don't know how it happened but its a very complicated process!!!!
A couple months ago i switched the servos in all 4 of my rc's(1 electric and 3 nitro) to 6.0/7.4v servos thinking it would be an easy switch over.......NOT
in an electric, IF your speed controler cannot be switched to 7.4 servo voltage, you either need to buy one thats capable OR wire in a BEC(voltage regulator)I use Tekin power. the version of the RX8 i have is not capable so i am either going to send both motor and esc in to tekin on a tradein for the newer versions o or install a bc. Castle makes a couple BEC's that you can adjust servo voltages with the castle-link. I own no castle products so castle-link would be a waste of $30 just to set a BEC, BUT your local hobbyshop probably has one and would set the servo voltages for you for little or nothing.

nitro........pretty much the only options are "high voltage" radio gear. a voltage regulator really isnt a viable option as i could not find one that would serve my purpose. A full 2s LiPo puts out 8+ Volts with a full charge and drops to under 6v when near depleted, i could not find one that would handle those extremes
I use flysky radio gear. from my investigations, people have successfully hooked the GR3b(they are listed as 6.0v capable only) recievers to 7.4V and had success, some have not. The GR3B is cheap and i have a few spares, but just have not purchased a 7.4v LiPo battery to test with. The other option is to switch your radio gear to a 7.4v setup. Spectrum make a fairly inexpensive transmitter that handles the voltage fine otherwise, BIG money on the other Radio gear manufacturers.

Now as far as 6.0v(non-highvoltage) servos getting fed 7.4V. I have read up on this a bit and my observation is that its 'a horserace a piece. some may handle the voltage and some may just fry out right away. If the servos do happen to work on high voltage, you can expect their life expectancy to be shortened as that is not their intended power voltage.
I wouldnt suggest hooking your 6v servos to 7.4v unless you really don't care what happens either way. just take the plunge and switch over to all high voltage servos

 

[jay2006]

I don't know how it happened but its a very complicated process!!!!
A couple months ago i switched the servos in all 4 of my rc's(1 electric and 3 nitro) to 6.0/7.4v servos thinking it would be an easy switch over.......NOT
in an electric, IF your speed controler cannot be switched to 7.4 servo voltage, you either need to buy one thats capable OR wire in a BEC(voltage regulator)I use Tekin power. the version of the RX8 i have is not capable so i am either going to send both motor and esc in to tekin on a tradein for the newer versions o or install a bc. Castle makes a couple BEC's that you can adjust servo voltages with the castle-link. I own no castle products so castle-link would be a waste of $30 just to set a BEC, BUT your local hobbyshop probably has one and would set the servo voltages for you for little or nothing.

nitro........pretty much the only options are "high voltage" radio gear. a voltage regulator really isnt a viable option as i could not find one that would serve my purpose. A full 2s LiPo puts out 8+ Volts with a full charge and drops to under 6v when near depleted, i could not find one that would handle those extremes
I use flysky radio gear. from my investigations, people have successfully hooked the GR3b(they are listed as 6.0v capable only) recievers to 7.4V and had success, some have not. The GR3B is cheap and i have a few spares, but just have not purchased a 7.4v LiPo battery to test with. The other option is to switch your radio gear to a 7.4v setup. Spectrum make a fairly inexpensive transmitter that handles the voltage fine otherwise, BIG money on the other Radio gear manufacturers.

Now as far as 6.0v(non-highvoltage) servos getting fed 7.4V. I have read up on this a bit and my observation is that its 'a horserace a piece. some may handle the voltage and some may just fry out right away. If the servos do happen to work on high voltage, you can expect their life expectancy to be shortened as that is not their intended power voltage.
I wouldnt suggest hooking your 6v servos to 7.4v unless you really don't care what happens either way. just take the plunge and switch over to all high voltage servos

all my 1/10th scale electrics have the castle mamba max esc..(4 of them) which the bec is switchable. but i was actually refering to my LST. i bout the speltrum metal gear high voltahge hybrid servos for the steering and just simple digital 6volt servos for throttle/brake and forward/rev shiftservo. i decided to get the 2 cell LIFE battery pack its 6.6 volts and dosnt really go much higher than that at fully charged like LiPo and NiMH does. fully charged its 6.9 volts and stays pretty steady around 6.6volts untill depleted around 5.0volts (so ive read) but i just charged it and its reading 6.9volts. i hooked it up to my LST today and i havnt ran it yet but just playing around with the servos and stuff it seems to be okay. all my RCs have spektrum radio gear.i have a spektrum DX3Rpro radio (50model memory,abs,traction control,idle up,mixing,backlite,telemetry) has all the goodies. and all the spektrum receivers are rated at 3.2-9.6 volts. so I'm really sitting good there.and my steering servos are rated at 163oz torque @7.4volts. so I'm good there. only concern is the other 2 servos rated at only 6.0volts.

 

[jay2006]

actually i should be in really good shape becuase i just measured the voltage on the NiMH pack i have for my LST and its putting out 6.54volts and i don't think its fully charged. so its about the same voltage as the LIFE 6.6 volt pack.

 

[jay2006]

OH and encase you guys are wondering... i picked up one of thoes new castle 1410 sensored motors today from my LHS when i picked up the LIFE battery. its the 3800kv 4 pole.i put it in my rc10t4.2 with my sensored capible mamba max pro esc..and let me tell you....that motor is amazing!!! i have another 1410 motor thats sensorless i have it in one of my traxxas stampede 2wds and its about the same power..maybe the sensored has a little more but man it is smooth as butter!!!! big time!its the first sensored system ive ever played around with .i had a castle 1406 5700kv in the rc10t4.2 but switched it out for the 3800 sensored. that truck is a monster with the 5700kv but its really a little beast now with that 3800. i love the top end and mid range speed of the 5700.and it wheelies all day long dosnt matter how high you gear it.but the 3800 is a more torquey motor..and you can control the torque better.but don't get me wrong my 5700kv is a torque monster also. really the only diffrence in power you can tell is the top speed is much better in the 5700kv. other than that the take off power is about the same in a 2wd application. put the 3800kv in a 4wd application I'm sure it will shine!! A PLUS FOR CASTLE FINALLY GETTING WITH THE PROGRAM LOL

 

[bifftit]

lower the KV more torgue and less top end
higher the Kv more top end less torque

I run a Tekin T8 1900kv in my savage flux