Shop our Airplanes Products Drone Products Sales
Thread Tools
Old Aug 23, 2009, 12:37 PM
Joel K. Scholz is offline
Find More Posts by Joel K. Scholz
Registered User
Joel K. Scholz's Avatar

Can running too many servos (4) on a speed control and 3s battery, damage the speed c

I am running into something I have never encountered before. I have added a moveable CG system to my Hawkeye utilizing a Dualsky 40 amp speed control. This control has a 3 amp BEC rated for 4 micro servos on a 3s lipoly. I have 3 micro servos and a high torgue servo on the system. When hooked up, the motor refuses to turn and makes a screeching sound. I hook up another speed control ESkY 25 amp control with dual BEC and motor runs normally. I disconnect all servos and use original 40 amp on motor alone. Motor screeches and will not run. I put the same speed control on a different motor and it operates normally? I am afraid to hook up a new 40 amp controller to the setup as I am afraid too many servos could damage the controller. any ideas as to the problem?
Sign up now
to remove ads between posts
Old Aug 23, 2009, 12:55 PM
Xpress.. is offline
Find More Posts by Xpress..
Team Hitec, Customer Support
Xpress..'s Avatar
High torque servos can draw more current, so theoretically you could be over running the ESCs BESC, causing it to shut down or refuse to work properly.

Use a seperate BEC and you won't have problems
Old Aug 23, 2009, 12:56 PM
matttay is offline
Find More Posts by matttay
Registered User
An ESC will have one or two thermally protected regulator for your servos. If you draw too much, it shuts down until it cools a bit, then it turns back on.

Most likely you haven't broken your ESC with the load, but something else is going on.
Old Aug 23, 2009, 12:57 PM
pilotpete2 is offline
Find More Posts by pilotpete2
Registered User
pilotpete2's Avatar
I would not use the built in 3A BEC with that high torque servo for the CG in the mix with three micro servos, that servo for the CG will pull some real current while shifting things, I would think
The issue with the motor screeching and not turning sounds like either a timing issue, or one motor wire connection is bad.
Good luck,
Old Aug 23, 2009, 01:00 PM
Xpress.. is offline
Find More Posts by Xpress..
Team Hitec, Customer Support
Xpress..'s Avatar
Also, potentially you could fry the servo if the loads on the CG mechanism are too great. Hitec has some new digital servos that draw significantly less current than previous models but put out MORE torque
Old Aug 23, 2009, 02:32 PM
keyman923 is offline
Find More Posts by keyman923
Former Futaba employee
Sounds like a motor timing problem?
Old Aug 23, 2009, 02:47 PM
gyrocptr is online now
Find More Posts by gyrocptr
Registered User
Motor "screeching" is discussed in following thread:

See post #1090
Old Aug 23, 2009, 09:29 PM
highflier is offline
Find More Posts by highflier
Speed cost money.
highflier's Avatar
Yes to many servos can damage the ESC. If the ESC has a linear bec the rating or 3 amps is likely to not be with a 11.1 volt battery. More like 2 amps. If you have a switching bec built in then it most likely will handle 3 amps with an voltage you use.

Old Aug 23, 2009, 09:45 PM
Ron van Sommeren is offline
Find More Posts by Ron van Sommeren
homo ludens modellisticus
Ron van Sommeren's Avatar
About BECs, #servos and battery voltage:

About de-rating controllers and motors, starting at 'for everyone else':

Vriendelijke groeten Ron

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Too many Servos for BEC? damiens75 Electric Sailplanes 5 Jan 21, 2005 06:14 AM
oops!, too many servos? Griffin Aerial Photography 12 Dec 29, 2004 07:14 AM
Anyone running Mega 22-20-4 on 10 cells ? Al P Power Systems 1 Jun 11, 2004 01:18 PM
Crazy Max too many servos. Please read aireze Parkflyers 7 Jan 27, 2002 08:28 PM
Too many Amps out on AA NIMH, 4/5A NIMH? sammy Parkflyers 2 Jan 27, 2002 12:52 PM