Identify connectors.

[J.N.]

Many months ago I bought a power train package along with all the bits to build my first electric flight model. The Motor is a BMI Spitz 85572, the ESC is unbranded but with a 40A sticker on it.

 

Apart from the ESC battery plug, there is no identification on the motor leads or the leads from the ESC to motor. I am at the motor fitting stage and before parting the connections I labelled them up by fitting coloured heat shrink tubing. I must have mixed up the leads because when I powered up the motor it juddered around at slow revs until I could kill the power after about 5secs. I swapped the leads around which resulted in a whistle type of sound and I again cut the circuit after 5 secs.

 

Can someone please let me know how I can identify the leads ESC too Motor. I tried a continuity tester but found that there was a circuit at any two of the 3 inputs to the motor. I then thought to connect the ESC to battery and Receiver and try to find a voltage rise at 2 of the ESC 3 outputs to the motor but gave up as I really do not know what I am doing. No visible damage has occured, there has not been any smoke or signs of heat.

Thanks.

[John Privett]

Assuming it's a brushless motor it will have 3 leads. There will also be three leads for the motor from the ESC. It doesn't matter which ESC leads you connect to which motor leads. The motor should run. You've got a 50:50 chance the motor will run in the wrong direction, in which case simply swap over any TWO of the leads. Simple!

[Tim Mackey]

And, maybe a read of THIS might help too

[Andy Gates]

From reading your post, it sounds like the connections you are making are correct.

 

The description you gave of the motor reactions sounds like the ESC needs to be programmed correctly for an outrunner motor with hard timing.

 

Check the instructions and get the ESC programmed.

[J.N.]

Posted by Andy Gates on 19/11/2011 22:15:57:

From reading your post, it sounds like the connections you are making are correct.

 

The description you gave of the motor reactions sounds like the ESC needs to be programmed correctly for an outrunner motor with hard timing.

 

Check the instructions and get the ESC programmed.

 

 

 

The ESC is un-branded and I was not supplied with any instructions for any of the power train. The ESC is covered in heat shrink tubing, would it help if I stripped off the covering and included a photo in the hope that someone can identify it and advise accordingly.

 

[DH 82A]

J.N.. try this :- First, do not have a prop on the motor.

 

Next, connect the three motor to ESC wires. Now plug in the ESC to your receiver motor socket. Now switch on your transmitter, and move the throttle to full power.

 

Now, (and only now,) connect the battery. There should be a few "beeps", or a tune sound, now move the throttle to off, there should now be more beeps or tune.

 

Pause a few seconds, then slowly open the throttle, and the motor should run, following the movement of the throttle stick. If the motor is running "backwards" , disconnect battery and swap any two motor to ESC wires.

 

[J.N.]

Posted by DH 82A on 20/11/2011 13:21:58:

J.N.. try this :- First, do not have a prop on the motor.

 

Next, connect the three motor to ESC wires. Now plug in the ESC to your receiver motor socket. Now switch on your transmitter, and move the throttle to full power.

 

Now, (and only now,) connect the battery. There should be a few "beeps", or a tune sound, now move the throttle to off, there should now be more beeps or tune.

 

Pause a few seconds, then slowly open the throttle, and the motor should run, following the movement of the throttle stick. If the motor is running "backwards" , disconnect battery and swap any two motor to ESC wires.

 

 

 

I am very gratefull for your help everything is now working as it should. Motor, ESC, Battery and Transmitter are all speaking to each other after I swapped over a lead. The long beeps or whistling noise I was worried about has now turned into a long beep that appears to be an audible warning that the system is "armed".

 

Until I become more confident and experienced I may go for an external in series connection for the battery positive lead and connect/disconnect when in the pits.

Thanks again.