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Old Aug 03, 2004, 06:26 AM
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Brushless - 2 Motors from 1 ESC ?

Probably an easy question for those in the know - can I run 2 brushless motors from 1 brushless speed controller (amp rating permitting, obviously) ?

I suspect the answer is "no", cos doesn't the ESC do some back sensing from the motor ?

Thanks.
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Old Aug 03, 2004, 06:55 AM
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Usually no, but some motor/esc combinations do work ... for example Kontronik sell a "twin drive set" with two motors and a single (normal) ESC which works fine. If you run some searches this crops up fairly often ... you might find other examples of specific setups that have been tried.
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Old Aug 03, 2004, 06:58 AM
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You got it. The answer is "no" for just that reason. That's what was explained to me when I asked about it. I pretty much decided to use brushed motors at that point so I never really got into the wiring aspect of it --- so I'm not sure about BEC. I suspect that if you use a "Y" harness to connect 2 ESC's to your throttle channel they would be running parallel and the voltage would be safe for your radio, but I'll accept the word of someone who understands this better than I do.
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Old Aug 03, 2004, 01:04 PM
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Quote:
Originally Posted by zeuglodon
You got it. The answer is "no" for just that reason. That's what was explained to me when I asked about it. I pretty much decided to use brushed motors at that point so I never really got into the wiring aspect of it --- so I'm not sure about BEC. I suspect that if you use a "Y" harness to connect 2 ESC's to your throttle channel they would be running parallel and the voltage would be safe for your radio, but I'll accept the word of someone who understands this better than I do.
The wiring would be in parralel; it would not double voltage. So, you use the two ESC's w/ a Y harness.

--Alex
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Old Aug 03, 2004, 01:38 PM
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Some peple have got it to work, with identical motors. Others have had problems with one motor not starting properly.

There's a video here of it working really well, apparently the poster took no special precautions, it just worked for him.
http://www.rcgroups.com/forums/showt...7&page=2&pp=15

Once running, they should be OK if the motors are turning at the same speed. If one is slightly slower it should draw a bit more power to keep it in sync, but if they get wildly out of sync the controller will get confused.

Robin
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Old Aug 03, 2004, 02:33 PM
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Stavanger, Norway
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Two BL (sensorless) can operate on one ESC but what limit success is start-up of both motors. Once running they run in perfect sync and the ESC see only "one". The key is getting a ESC with appropriate (tolerant) start-up algorithms. Using two identical motors is important, also keeping the motorwires (the pair of three) identical in length.

Some combos work, others dont. By reports here on the Ezone Kontronik ESC's offer the greatest chance of success. Motorbrand is less important, ESC is the key.

One can only parallell such a system so your ESC need atleast 2x amp rating of one motor/load.
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Old Aug 03, 2004, 07:49 PM
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Who carries the Kontronic ESC's?
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Old Aug 03, 2004, 08:03 PM
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Greg,

You can get them from Perry at AeroMicro, although I have always bought mine used here on the 'zone.

My success rate for twins is 100% Kontronik, 0% other (CC, TMM, Jeti).

= Mike
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Old Aug 04, 2004, 05:27 AM
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It works! Just do it!
Scott
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Old Aug 04, 2004, 11:21 AM
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I made 2 CD motors for a friend and they start and run perfectly on a Tsunami 10 in its default 'mode3' setup. They both have the same number of turns and are connected in parallel (how else?!). I wanted him to connect the same winds together (A to A, B to B etc) but he forgot so we're not sure if he did this or if this is important or not. He now wants a 4 engined model on one ESC; oh no, my fingers are sore!
David.
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Old Aug 04, 2004, 02:45 PM
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According to Castle Creations it is not possible to run two brushless motors from one ESC ... well, theirs anyway

http://www.rcgroups.com/forums/showthread.php?t=259943
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Old Aug 04, 2004, 03:20 PM
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Arlington, TX
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My P10 and P25 work just fine with 2 motors and one controller. I know several others running them this way with no problems.

Tracy Hill
Conversion motor works
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Old Aug 04, 2004, 08:08 PM
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And I've tried both the P10 and P25 in dual configurations with consistently poor results. I can say for sure they don't reliably start Astro or Mega motors like this.

Perhaps a better way to state it is like this:

Castle Creations explicitly say that their controllers are not designed to run more than one motor in parallel.

Kontronik explicitly say that their controllers are designed to run more than one motor in parallel (and they sell a product based on this).

= Mike
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