Hi I'm somewhat new to building fixed wings. I have been using cheaper motor, esc kits fro Ali Express. I have started printing planes so figured I'd spend a bit more on electronics and picked up some Emax BlHeli ESCs. The ESCs I have been using were BEC the new ones are UBEC. If I hook up the UBEC ESCs to channel 3 like I am used to the servos power up but motor does nothing. I have a steady 5vdc on the FC. I have tried programming the ESC as the manual says with the transmitter but cant get anywhere. Do I need another module to go in parallel with the ESC now or what am I missing?
Help! Ubec vs bec
- Thread starter Rodpil
- Start date
Shurik-1960
Well-known member
BEC ESC has 3 wires: "+" "-" and a signal (the wire that controls the engine speed) . UBEC is a simple 5 volt receiver power supply, which is used for non-motorized models. I didn't quite understand your thoughts. Draw a diagram of what and where you want to connect and it will be easier for us to give advice.
Shurik-1960
Well-known member
This is the first time I see such a UBEC. Usually the output is 5 volts , your 3 A . Why there are 3 wires at the output - I don't know. Put the usual ESC and you will be happy.
Lol to many other RCs between mine and the kids. I have used up all the other ESCs in them and thought I would try something that would handle a bit bigger battery. The output is 5vdc, so thats proper but seems like the signal wire doesn't do anything. Been looking around and a bunch of ubec ESCs are a similar set up. Didn't think it would be much different then the traditional ones but I guess I am wrong lol.
Rhaps
Elite member
I think thats just regular esc - even if there is ubec written in it. Googling for 40 A UBEc gives a lot of esc:s that are advertised as esc with ubec . Makes no sense but who's gonna sue them 
The 3-color wire from the motor is weird tho, none of my morors have something like that. I'd actually guess its for voltage meter or such.
What happens if you just take the 3-color wire coming from motor and disconnect it from receiver?
The 3-color wire from the motor is weird tho, none of my morors have something like that. I'd actually guess its for voltage meter or such.
What happens if you just take the 3-color wire coming from motor and disconnect it from receiver?
Sorry its a confusing picture i guess. This one, which was easiest to take a picture of is for an airboat. The three colored wire going up to the motor is a servo that is mounted behind it gor the rudder. I've tried this exact motor and servo set up with older ESC i have and it works fine. Seems like im doing something wrong with these new ESCs I picked up.
Shurik-1960
Well-known member
Start by calibrating the ESC : the joystick is turned up on the switched- on transmitter all the way up , turn on the transmitter . Connect the battery to the ESC. The motor should make a sound-trills, music... set the joystick down. Calibration is complete. If the motor does not emit anything, then most likely the signal wire from the ESC on the board is not soldered.Start with calibration.
Ya I've tried calibrating based on the manual it came with and good old you tube. Esc makes no noises at all. With the old ESCs the motor will twitch when power it applied, but these EMAX ones nothing. I just think it is odd that both are doing the same thing, guess could be a bad batch? Also tried it with my radiomaster set up and got the same results.
Shurik-1960
Well-known member
ESC never makes any sounds.The sounds are made by the motor through the winding. You need to go to a phone repairman who will check for a breakage and will be able to see the control signal on the oscilloscope. If you were in Russia, I could watch it for free, but alas.You can check with a soldering iron (heating to desoldering) all the connectors from the motor and ESC .... I always connect the motor to the ESC only by soldering, because there were failures in flight due to poor contact.
Shurik-1960
Well-known member
ESC is disassembled very easily- the shrink is cut with a stationery knife and ...photos to the studio of both sides.
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