esc

[bentech]

hi guys!! i want to drive a brushless motor with a esc for non r/c application.
how can i change the rpm of the motor without a rx and tx system.
i heard that some peoples use a servo tester as a dimmer switch for
driving a d/c motor. is it possible ??

[Tomapowa]

hi guys!! i want to drive a brushless motor with a esc for non r/c application.
how can i change the rpm of the motor without a rx and tx system.
i heard that some peoples use a servo tester as a dimmer switch for
driving a d/c motor. is it possible ??
Yup... most servo testers output the proper PWM signal needed to control ESCs. It's not really a dimmer... but rather a PWM signal generator (1-2ms pulse every 20ms). You could also easily use a PIC that is programmed to output the proper PWM signal.. or simply use this 555 timer circuit (i.e. servo tester):
http://www.uoguelph.ca/~antoon/gadgets/servo3.htm

The other thing to be concerned of is the arming of most ESC. Some like to see a low throttle setting (1ms) for a bit before arming/controlling the brushless motor. Some make you first cycle the throttle (1ms/low, then 2ms/high, then back to 1ms/low) in order to arm the ESC.

[Andy W]

I use one of these:
http://search.hobby-lobby.com/psearch/public/services/visitItemAtWebsite.php?uid=1&pid=2156

Invaluable, when installing or testing motors. For $10, can't be beat.
..a

[bentech]

cool !! thanks.

how do i plug the e.s.c / battery / motor / servo tester all together ??

battery to e.s.c, motor to e.s.c, and the 3 wires connector of the e.s.c to
the servo tester output ??

[slipstick]

how do i plug the e.s.c / battery / motor / servo tester all together ??

battery to e.s.c, motor to e.s.c, and the 3 wires connector of the e.s.c to
the servo tester output ??
Yes, you've got it...provided that the ESC has a BEC and so will provide the necessary power to the servo tester. Otherwise you might need a separate 4.8V battery to power it.

Steve

[Andy W]

What he said.
I keep an old, small 4-cell NiCd pack velcro'd to the back of my tester for when it is needed (I have a few high-power systems that use ESC's that have no built-in BEC)..
..a