servos at 4.4V?

[BrendanP]

I've checked around and it appears to be "doable" but I thought I'd run it by the forum.

Will garden variety RC servos run OK, albeit a bit slower, at 4.4V? I'm limited in V available on the board I have.

 

[premelec]

I don't think there's a simple answer - it depends on the servo and some may work and some don't - have you read the spec sheets of ones you are interested in? Note that when they run they can pull hard on the supply and further complicate things - or go for empirical result - just do it - and then add more juice if needed...

 

[John West]

It's not a matter of it running slower. It will run with lower torque (force.) Whether or not it will operate with sufficient power for your needs will depend on your application.

 

[John West]

OT: Happy holidays, P. I'm in MI. Will be back to CO on Jan 5th.

 

[premelec]

Ok John... no snow yet here!

With the servos the electronics may not work - not just motor torque failure..

 

[BrendanP]

Thanks guys.
I'm using the Hitec HS-311 to operate a pan tilt with a pcb on it. The data sheet says it requires 4.8V to 6V. I''l do some test and see if I stretch "push the friendship".

 

[John West]

Test the servos in their actual application, if you can. Changes in temperature and load and such may cause them to become unreliable. But the voltage you are running is close enough to spec that it's possible to likely they will work just fine.

 

[BeanieBots]

Most of the servos I have are quite happy down to ~3.5v.
They DO slow down and they DO get weak but they still function OK.
Many have their center position drift off with low volts which can be problem.
When used in regular RC equipment it's often the Rx unit that fails first on low voltage.

 

[BrendanP]

Thanks guys, the servos are for the same project as the FET hence (because of pcb space restrictions) if we can use the 4.4V supply we have it well help things with pcb layout.

 

[BrendanP]

These Hitecs will still operate at 2.3V.

 

[westaust55]

In terms of your initial intent to operate the servo's down to 4.4 Volts, seems it should not be a problem with the servo (but will reduce the speed and torque).

I found this:
[quote}
I only use Hitec servos. They'll also keep running down to 4.2 or 4.4v or so, and don't go bonkers [smash over to the end-stops] when the voltage drops too low.
{/quote]
at: http://dics.voicecontrol.ro/process_mails/arata_discutia/118969/7.2_Volts_for_Hobby_Servo's.html

so while the initial request was about operation at a higher voltage others have been looking at lower voltages as well.

 

[BrendanP]

Thanks Westaus.