hitec 7950 getting too hot
 

Iam running novak m2 dig and a traxxas tq3 radio and reciever with a 1600 nimh 7.2 volt battery in my xr 10 and my hitec 7950 servo is getting so hot you and even hold a finger aon it, Running same set up on my bodiles bully mod and every thing is running alot cooler any suggestions

Re: hitec 7950 getting too hot
 

Are you running a BEC? I am running a BEC directly to my 7950 servo at 7.4 volts. Sounds crazy but once I cranked the volts it started running cooler. Also try to pay attention to when your crawler is sitting idle with the power on, is the servo buzzing? Wiggle the steering if it is just sitting and buzzing. That is the servo trying to center and heating up then.

Re: hitec 7950 getting too hot
 

My servo is constanly buzzing unless you pick it up off the ground Iam not running a bec on either set up How would i center my servo or keep it from buzzing

Re: hitec 7950 getting too hot
 

Check for anything binding in the steering components,and turn your steering EPA'S down so your not over working the servo.

Re: hitec 7950 getting too hot
 

I definitely recommend a BEC. $25 isn't a big investment to properly power a $150+ servo. Definitely check for binding. It doesn't take much. Disconnect and make sure the steering cycles very easily. Picking it up is good or sometimes you can give the controller wheel a quick jiggle. Its fine to buzz when cycling during driving just be sure not to let it buzz constantly when just sitting still. that sound is it trying to center itself. Also like said before check your endpoints. I usually set my endpoints by picking up the front of my crawler and turning the wheels with the controller. I then adjust the endpoints on the controller until the steering starts to bottom and I hear the servo buzz. Then I back it off a bit that way the servo never reaches the binding point after its set.
Hope this make some kind of sense I have a habit of explaining things the hard way.

-Trent

Re: hitec 7950 getting too hot
 

A little less of a tech answer, How long of a servo horn do you have? Remember servo power goes out the longer you have the link mounted to the horn. Causing a tough time to center and aiding in heat build up.

Re: hitec 7950 getting too hot
 

Buzzing (to a bit) is normal for digital servos.
-Make sure the steering linkage is not binding
-Make sure the servo horn is not binding on the top of the servo case (I had a chaep aluminum horn bind)
-Get a 10A BEC once you up the pack voltage (add a cell, go to 3S LiPO)

Your starting pack voltage is about what the servo wants, it quickly drops thus running it to a low voltage. This will be too low for a external BEC to work properly.

Re: hitec 7950 getting too hot
 

With a TQ3 you dont have end point adjustment so that's probably generating a lot of heat as well as ruining your servo.

Re: hitec 7950 getting too hot
 

End points are a must to keep the servo alive among other parts.And I would also add a adjustable bec and jack the voltage up.

Re: hitec 7950 getting too hot
 

One major feature most guys forget about is the deadband width on the servo. What that is, the servo has a center, that center is the deadband zone, think of the deadband zone has a dimesion. If that dimension is tight/small the then servo will cycle left and right very fast to acheive center, kinda "bouncing" left and right, creating heat and using battery power. The deadband width can adjusted to open it up just a touch so it wont "bounce" as much creating less heat. However, you will need a servo programmer to access that feature. Check with your hobby shop or you may want to look at ordering one. Then you will have it to program your friends servos as well as most of you other servos as well.

PM me if you need more info

Re: HiTec 7950 getting too hot
 

If he is only running 7.2 volts from the pack, he CAN'T jack the voltage up. Sorta what I stated in my earlier post.:roll:
The BEC can only supply up to (actually a little short of) whatever voltage is from the pack.

Maybe running the servo power (red & black wires) direct from the input wiring to the ESC will help, it gets the ESC BEC out of the circuit.
The 7950 is a power hog (my son & I both run them), it really WANTS in the low to mid 7 volt range."thumbsup""thumbsup"

Re: hitec 7950 getting too hot
 

Old thread but I'm having the same issue. Hooked up both a 7950 and 7954 directly to my bec running 7.4v and after about 10minutes it gets scorching hot. I've adjusted the epa, checked for binding at the horn or in the steering but still can't determine the problem. I'm gonna tear it down at my next available opportunity and do process of elimination but thought I'd check here in the meantime to see if anybody has been down this road before.

Re: hitec 7950 getting too hot
 

Did you check clearance between the bottom of the horn and the top of the case? I had a cheap servo arm with a deep spline pocket, the bottom of the arm was against the servo case.

Yup, it looked like a snug fit even though it is a hitec horn as well. Trimmed the top of the servo down thinking that had to be the problem. No dice though.

Re: hitec 7950 getting too hot
 

Are you running the stock steering?
If you, look in to a longer arm for the stock steering knuckle, can be found here. TowerHobbies.com | Axial High Leverage Steering Arm
Second, ditch the stock steering linkage, go with a solid rod. Chaotic Crawlers was making titanium rods in lengths for the stock and vanquish knuckles.
I had the exact same problem you are describing with my XR10 when it was stock, but was using a S9157 Futaba servo. After a 5 minute run the servo was just about smoking hot.
Made these two changes, problem went away.

Re: hitec 7950 getting too hot
 

Here's my setup:
VP hubs and knuckles. VP drag link and tie rod. Here's a pic if it will help. Seems to me that for it to get that hot that quick there would need to be some major friction somewhere.

http://i1096.photobucket.com/albums/...-08-37_963.jpg