Hi am making my first drone using Pixhawk 2.4.8, and I want to add a servo motor.I saw on the documentation that I have to power the servo rail with a 5v battery to do that and also to use a Zener diode to prevent any spikes that can harm the Pixhawk. Should I connect the components like in the scheme below?
-Servo model: Feetech FS90R
-Bec model: bec
I have never used a zener diode in any of my bec connections. but all other connections you have there are 100% correct. as long as your bec provides a stable reliable voltage I don’t see a need for a zener diode. just get a good quality bec.
Thanks for your reply ! Do you know how to choose a good bec ? I bought this one bec link do you recommend something else ?sorry for these questions but i am a complete begginer in all this.
Or don’t connect it to the servo rail and power the servo directly.
It all depends on many things but the one you have link I have one that looked identical to yours on a old pixhawk build never had any issues. If you are going to be hanging expensive equipment off of this keep in mine skimping on cost early on from unknown manufactures can lead to some very bad results. a lot of this depends on your over all goal and obviously budget. Mauch power supplies are some of the best out there and are reliable but some time shipping costs can be prohibitive depending on where you live looks like from your like is Greece? you could also as @dkemxr says create a separate rail that just powers the servos of you copter. That does add a level of difficulty. What will the servo be doing?
Yes I am from Greece and its a little difficult to find variety of products here, but I will look if there is any bec of this brand! I am buidling for my thesis an agricultural drone which will be able to fill with water its tank and I am trying to make a linear servo actuator which will lower the tube of a pump in order to suck water to fill the tank.
Yes. Can’t go wrong with that.
ok I will try it I hope it works! thanks for the help
can i ask you something else should i also connect the ground of the servo rail to the ground of the bec or is it ok in the scheme above?
I would say yes… but @dkemxr can tell you better… you need to warrant that you have a common ground somewhere, not exactly at the connection shown in the image
Often times you will need to keep a common ground you can try to hook it up like the photo you posted but if you see that it is not functioning it is more than likely you need to keep common ground between the two. it may also work considering you will probably share a common ground among the battery or another connection.
@dkemxr
Hi Dear
Can you help me in how to connect servo motor in 9,10 channels in pixhawk2.4.8 flight controller.
Power the servos from a BEC and connect the servo signal leads to Aux 1 & 2.
Hi Dave,
All signals need the same reference, therefor the GND of the BEC must be somewhere connected to the GND of the pixhawk.
I think, this should be added to your advice for better understanding
Hello.
Maybe an old topic but I’ll give it a try.
When the Aux rail isn’t powered it is possible to connect a servo directly to the receiver itself. Servo will work. Recever gets the power from the pixhawk so the servo also has power to work.
My question is this an alternative way to connect teh servo. I use rover in a boat and I want the pixhawk t do the steering only. Other functions directly from the receiver. Is this a good idea or better to power the powerrail on the pixhawk and let the servo work through the pixhawk?
If you want to control the servo by the FC you have to connect the signal line and GND of the servo to the FC. Servo power and GND can be connected seperate.
Controlling a servo from the FC through the RC receiver is not possible
Hi Juergen,
Thanks for your reaction. Do you mean that controlling a servo from the RC receiver is not possible or that it isn’t the prefered solution. When I connect left and right throttle to the FC and the servo to the RC recever it works. RC recever has power through the connection with the FC and it looks possible but I’m a bit worried if its relaible. I solved the issue by taking the power of one of the speed controllers and put it on the servo. Signal and ground of the servo will be connected to the FC aux
