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Author Topic: twin motors off one speed controller  (Read 6333 times)

tugs62

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twin motors off one speed controller
« on: July 20, 2014, 07:16:41 pm »

Help needed can i run two brushless motors from one speed controller or do i have to use two controllers
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malcolmfrary

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Re: twin motors off one speed controller
« Reply #1 on: July 20, 2014, 09:42:13 pm »

A brushless motor is only half a motor.  The other half is the brushless ESC.  Just as there is no such thing as a brushed motor with two sets of windings and one commutator and set of brushes, you do need each brushless motor to have its own ESC.  Whether these ESCs are hooked into the same control channel or not is another question again.
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Time Bandit

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Re: twin motors off one speed controller
« Reply #2 on: July 20, 2014, 10:23:30 pm »

Theoretically itīs possible to run 2 unsensored BLDC motors with 1 ESC.
BUT,
itīs a matter of luck if it is working or not. So at the first startup it can work, at next startup not.
If you mechanically synchronize the 2 motors with a belt or something it will work.

So if you have no mechanical synchronisation use 1 ESC for each motor.

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regards

Tobias

tugs62

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Re: twin motors off one speed controller
« Reply #3 on: July 21, 2014, 09:27:54 am »

Can I still use one channel for both esc
Cheers Brian
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nick_75au

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Re: twin motors off one speed controller
« Reply #4 on: July 21, 2014, 09:38:53 am »

Yes, a Y harness is needed, both ESCs need to be programmed as a pair to ensure they are synchronized, that is program the throttle end points of the ESC.
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tugs62

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Re: twin motors off one speed controller
« Reply #5 on: July 21, 2014, 11:52:49 am »

Thanks  :-))
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mrlownotes

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Re: twin motors off one speed controller
« Reply #6 on: July 21, 2014, 06:43:58 pm »

Yes, a Y harness is needed, both ESCs need to be programmed as a pair to ensure they are synchronized, that is program the throttle end points of the ESC.
If both your ESCs have BECs then make sure to disable one of them from the RX. Maybe remove the red wire from the RX plug and tape it back to isolate from the RX.

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Bintur Ellenbach

wizard

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Re: twin motors off one speed controller
« Reply #7 on: August 28, 2014, 01:49:11 am »

I have done this on several of my models but don't really understand why it is necessary. Can someone tell me.
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mermod

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Re: twin motors off one speed controller
« Reply #8 on: August 28, 2014, 03:04:16 am »

Hi Wizard, the BEC or Battery Eliminator Circuit supplies power to your receiver, if you don't disconnect one of the red leads you are supplying 2 lots of power to the receiver.

Phill
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wizard

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Re: twin motors off one speed controller
« Reply #9 on: August 28, 2014, 04:51:19 am »

Thanks for that Phill. I still don't really understand. If both BEC supply say 5 volts through a y lead isn't that still 5 volts?
You can see by my questions that I don't really understand electrics, I usually just follow instructions and things seem to work.
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Plastic - RIP

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Re: twin motors off one speed controller
« Reply #10 on: August 28, 2014, 07:56:21 am »

Thanks for that Phill. I still don't really understand. If both BEC supply say 5 volts through a y lead isn't that still 5 volts?
You can see by my questions that I don't really understand electrics, I usually just follow instructions and things seem to work.

Each BEC is generating a nominal 5V but there will be a tiny difference in their '5V' voltages due to internal component tolerances. Each regulator circuit looks at its own '5V' output and adjusts itself to keep it constant regardless of load current up to its maximum output.

If you connect 2 together, each will fight the other trying to correct their individual outputs to what they think is 5V - they will push more and more current around the loop until they overload each other - things will get HOT! If you're lucky, one will shut down first because of good circuit design - if you're unlucky, one will blow up and the other may be damaged.

If you're really unlucky, both will be fried.  {:-{

This will happen in a couple of seconds - you won't be fast enough to stop it and the smoke and heat you see and feel on the outer case of the ESC is nothing compared to the destruction inside the unit.


Cut the wire - it's much cheaper!
 
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malcolmfrary

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Re: twin motors off one speed controller
« Reply #11 on: August 28, 2014, 09:22:37 am »

Rather than cut the wire, just winkle the connector out of the holder and tape it back in a tidy manner.  That way, you can always put it back where it came from to re-use it should the need ever arise.
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inertia

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Re: twin motors off one speed controller
« Reply #12 on: August 28, 2014, 09:45:51 am »

Like this:
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wizard

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Re: twin motors off one speed controller
« Reply #13 on: August 28, 2014, 10:48:05 am »

Thanks for the explanation. I always wondered about that.
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mermod

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Re: twin motors off one speed controller
« Reply #14 on: August 28, 2014, 10:56:01 am »

Nice graphic  :-))
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inertia

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Re: twin motors off one speed controller
« Reply #15 on: August 28, 2014, 12:25:22 pm »

Thanks. There's a few more of them here which you might find useful http://www.action-electronics.co.uk/wd.php
DM
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tugs62

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Re: twin motors off one speed controller
« Reply #16 on: August 29, 2014, 06:25:50 pm »

Thanks for all the help  :-)) :-))
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robw

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Re: twin motors off one speed controller
« Reply #17 on: August 29, 2014, 06:34:43 pm »

Help needed can i run two brushless motors from one speed controller or do i have to use two controllers
http://alienpowersystem.com/shop/boat-esc/alien-300a-3-16s-boat-esc-hv-twin/
this might help?
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tugs62

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Re: twin motors off one speed controller
« Reply #18 on: August 29, 2014, 09:13:54 pm »

thats a nice bit of kit but way out my price range  :-))
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