RC India

Can anyone please suggest whether we can run a brushless motor in reverse and forward through transmitter without changing the set terminals...?

I want to use this feature in a boat for forward and reverse....

The motor I am using is Turnigy 1000kv one...

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=12921 (http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=12921)

ESC used

http://www.hobbyking.com/hobbyking/store/__13429__HobbyKing_30A_BlueSeries_Brushless_Speed_Controller.html (http://www.hobbyking.com/hobbyking/store/__13429__HobbyKing_30A_BlueSeries_Brushless_Speed_Controller.html)

Thanks in advance...!

Dont think its possible!!!

Typically you would get an ESC that supports reverse functionality out of the box, like the ones used in RC cars. 

But I wonder if some of the regular ESC firmwares can be hacked into supporting reverse, like how the custom SimonK firmware is loaded onto ESCs used for multirotors. Comments ?

You'll need to hunt for readily available firmwares. There're many nowadays :SimonK, Wii-ESC, BLHeli....
Or write one on your own.

I think i have seen a tutorial post by our very own Roopesh sirjee how we can reverse motor with TX using 2 servos and a switch i guess.. Please search for Roopesh krishna Sirjee's post

As far as I remember that was an electromechanical setup. I don't think that is what Adiboy is looking for.

Why not, he had one servo if i rem, which triggers a switch which reverse the ESC connection to motor, if we connect that servo cable to a RX's AUX channel then this is possible, still i would suggest finding that tutorial by sirjee..

Adi, you need a different ESC for it. Lets talk tomorrow (this time, hopefully, successfully!).

Thankyou Everyone for replying...

@hyd_quads

Sir, as per my understanding change in the direction can be done by reversing the direction of current flow.

Let's say the brushless motor wires are A, B, and C and the rotor is at 0 degrees. Each time the sequence "steps" the rotor spins 1/3rd of a rotation or 120 degrees:
step #1: A-B (A is made positive and B is made negative, and C is left at nothing) becomes energized and rotor spins to 120 degrees,
step #2: B-C becomes energized and rotor spins to 240 degrees,
step #3: C-A becomes energized and rotor spins to 360 degrees (0 degrees)

So you can see each wire is positive for 120 degrees of a single rotation, negative for 120 degrees of a single rotation, and not energized for the remaining 120 degrees of the rotation.

So for reversal we need to change the sequence i.e. change the direction of current flow and the sequence of magnetic energising.

MORAL : It might not be possible by software changes though I am still not sure...

@Satyagupta Sir

I couldn't find Roopesh Sir's thread but as you are saying I get it what it might be.... He might have constructed an 'H' bridge circuit through switches which are in turn connected to servos and when operated, changes the direction of current flow....

@VC Sir

If there is any ESC like that with an inbuilt 'H' bridge... Please do tell me...

regards

Aditya

There are some ESCs by the brand name "Pentium" which can be reversed by a series of stick inputs. But this option serves a different purpose: when you have connected the motor to the ESC and want to change the direction of rotation without swapping any two wires.
This is just to say software changes are capable of doing what you require, but hey I am not sure about it too.
PS: Don't call me sir.

Vineet

 :giggle: :giggle: :giggle: Never mind... We shall rest our case in the hands of our senior members...!!

Exactly thats what he did...

And me no sir man please you can call me by my first name: Satya

Just make an interchanging option between any two motor terminal using DPDT relay triggered by an Servo on any extra channel.
Your purpose will be served.
But please Keep in Mind the relay contacts should be capable to handle of full motor current. However, this method is not suitable as any miscontacts in relay will blow out the motor windings. So must be limited with fuses too for safeguarding of windings.

 Best option is to use reversible ESC., No doubt.
They have no H bridge (for DC Motor), but they just changes the pulse sequence from micro controller. Hence phase shift and rotating torque direction reverse. Our BL motors are nothing but tiny 3 phase synchronous motor with very high power dencity (Achieved with Neo Magnets).

@ Kalyan Sir

Thanks a lot..

Now that you have talked about Neodymium Magnets... I need big size magnets around 10-15 for designing an alternator cum windmill setup... Do you have any idea Where can I get them..?

About BL ESC... can you suggest any good one on HK with programming card available in stock... I will straightaway order it.
I saw few car ESC's also compatible with boat and also dedicated boat water cooled ESC's... Can't decide...

Thanks..

Also just Neo Magic (irrelevant to the topic but fascinating for any age)

http://www.theneocube.com/ (http://www.theneocube.com/)

Greetings Everyone...

I have shortlisted these two ESC's among all... Everyone please share your views and help me to finalize one among these two...

http://www.hobbyking.com/hobbyking/store/__7188__Turnigy_Brushless_ESC_60A_w_Reverse_prog_v2_2_.html (http://www.hobbyking.com/hobbyking/store/__7188__Turnigy_Brushless_ESC_60A_w_Reverse_prog_v2_2_.html)

http://www.hobbyking.com/hobbyking/store/__7360__Turnigy_Marine_60A_Brushless_Boat_ESC.html (http://www.hobbyking.com/hobbyking/store/__7360__Turnigy_Marine_60A_Brushless_Boat_ESC.html)

This is the programming card compatible with both of them:

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=7187 (http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=7187)

There are a few cheap ESC's but their programming card is unavailable.

Thankyou...

can we control a brushless dc motors in both the directions through a 9 channel 2.4 GHz RF module?
if yes, then how?

[Admin Note] This post has been merged into an existing thread on the same topic.

@ Sudarshan

Yes we can do it... I haven't done it yet but found about Special ESC's which can help us achieve our goal. Those are Boat and Car ESC's available on HK..

@Adiboy:

Yes, firmware can make a normal ESC reverse throttle , etc. And you have a ready-made firmware for that. (from what I gather from this post): http://www.rcgroups.com/forums/showthread.php?t=1513678&page=412
(Pg 412, reply #6177 onwards) Enjoy! :thumbsup:

If i may ask .... why do you want to reverse the BL motor?

Hey,

To get the reversal of motor at an instant without changing its either wires.

Car ESC or a separately controlled relay which swaps two of the wires(not recommended though).

Greetings,

I have purchased the following ESC and also achieved the function of Forward and Reverse simultaneously...!

http://www.hobbyking.com/hobbyking/store/__24567__HobbyKing_30A_Boat_ESC_3A_UBEC.html (http://www.hobbyking.com/hobbyking/store/__24567__HobbyKing_30A_Boat_ESC_3A_UBEC.html)

Now just last doubt.

There are four brass pipes coming out of the same for Water cooling. Can anybody help exactly how can I achieve this feature...?

Thanks in Advance.  :salute:

may be you can use the similar cooling equipment used to cool CPU heatsink in computer. but this will add lot of weight to the model, not sure if you can use a water cooler in a plane or heli... :-). might be for some car and other other ground models u can use this ESC with water cooling