4 motor wiring?

[Den Moran]

Hi,everyone!

Does anyone know where I can get hold of a circuit diagram for a four motor setup, please?

I am also looking at differential thrust options, but would like the basics first! Cheers, and thanks, Den

[Former Member]

[This posting has been removed]

[Glenn Philbrick]

Depends on what model you are building. I have used a speed controller for drones to power 4 ducted fans, and also on my second lanc that I use individual controllers for each motor. In each case I have used a separate battery to power the Rx and retracts. There is a lot of discussion about which leads to lengthen which you will find on this forum somewhere. I have in all cases increased the leads to the ESC not from the ESC to the motor. Those with technical knowledge will tell you this is wrong but I have never has a failure yet.

Glenn

[andyh]

I don't have a diagram, but I'll try to describe it ...

split the power feed from the battery four ways to the four ESCs & bring the ESC servo leads back to the Rx. if you want differential thrust, you can Y the two port motors into one channel & the two starboard motors into another.

if you're using the BEC from one of the ESCs to power the Rx, disconnect the red cable from the other three. if you're using a separate BEC then disconnect the red cable on all four & connect the BEC to a spare Rx port, or Y it into an in-use channel if you're short of ports.

you don't say what radio you're using, but if you put "differential thrust mixing <radio type>" into youtube/google you should get some pointers.

I have differential thrust set up on my BushMule (just two motors, but same principle) for taxiing, mixed to the rudder & it will turn 180 in its own length which can be handy. I'm not brave enough to use it in flight though!

[Simon Chaddock]

Den

A wiring diagram for 4 brushless motors using an ESC BEC to power the Rx and servos.

Note only one red wire is connected. It is unwise to power anything from multiple BECs.

If the plane has many servos it would be better not to connect the ESC BECs at all and power everything from a separate UBEC.

Best of luck with differential thrust!

[Gary Manuel]

Den

I just have one thing to add, as you said you want to understand the basics.

Simon's circuit diagram is spot on and will give you independent control of all 4 motors using 4 radio channels, which allows you to programme differential throttles. I've used this arrangement on a Lancaster to great effect, but it does require that your transmitter is up to it. I had to use a few tricks to get mine to do what I wanted.

If you just want all 4 motors to run together over a single channel, just use 3 y-leads at the left hand end of Simon's circuit. i.e. two ESC leads into 1 Y-lead and two into another, then the two Y-leads onto the third Y-lead, the other end of the third Y-lead into the receiver throttle channel. Remember though, that only 1 red wire between the four ESC's and the first Y-lead should be left connected. Maybe you could try this first to check that all is working, then play around with throttle differential (rudder mixed with the four throttle outputs in varying degrees).

Out of interest, which transmitter are you using?

Edit - HERE's a link showing what I did with my transmitter to get differential throttle control of my Lancaster

Edit 2 - One important consideration if using differential throttles is your failsafe. It needs to work on all 4 throttle channels!

Edited By Gary Manuel on 25/08/2018 13:12:06

[PatMc]

Posted by Gary Manuel on 25/08/2018 12:59:27:

Simon's circuit diagram is spot on and will give you independent control of all 4 motors using 4 radio channels, which allows you to programme differential throttles.

AFAICS Simon's drawing shows all the ESC's on a single plug - i.e. combined control of all motors with no differential throttle control.

[Den Moran]

What a great response! Thank you ,everyone, it's certainly answered my question!

Gary, I have a marvelous Turnigy 9xPro that I am still finding out about - it's uses ErSky programming, and is used on lots of different 'makes' e.g. Taranis. I am used to mixing, and think this set-up'll be ok. Thanks also for your brilliant 'link'.

The plane I have in mind initially is a HK rudderless Lancaster. I am also planning a large Short Solent build, and would like the Differential Thrust for taxi-ing.

Thanks, again, everybody! Den.

[Gary Manuel]

Den

You should have no problem with the ErSky if it has similar capabilities to OpenTx.

Good luck with the HK Lancaster - they can be challenging to fly and everything that's been said about them is true. The key is to fly them quite fast with power applied all the time.

Pat

I interpreted the 4 cables (9 wires) into the receiver to be to 4 separate channels, but I can see how the 3 dots could be read as single terminals on one channel - with multiple wires on a dot representing Y leads. Either way, it works.

[Frank Skilbeck]

I'll just add another couple of notes

1) check the esc's will work if several are ganged together into one Rx port, sometimes splitting the position signal means it gets so weak the ESCs can't see the signal. This will be a function of the ESCs and the Rx.

2) I've used differential thrust on two twins, a twinstar and a Catalina, it works well for taxying and take off, don't mix too much in, I had the rudder input around 20% and it worked well. It made taxying the Catalina on water very easy.

[eflightray]

On my four motor models I use two battery packs, one driving the inner motors, the other the outer motors.

Two channels for differential motor steering on the ground.

There is recommended that the leads between battery and ESC are kept short, and the ESC to motor lengthened. Long battery leads need additional ESC capacitors.

B-17, Sunderland, and sadly now defunct Lancaster.

Ray.

http://www.eflightray.x10host.com/

 

Edited By eflightray on 26/08/2018 14:32:47