My question is about the automation of single phase AC motors.

I am aware that I can purchase TRIAC controllers with manual knobs or even 0-10V control inputs.

I am new to the world of AC controllers so I would like to know if there are many other kinds of controllers with different control inputs. If so which is the most suitable for automating with an output from an Arduino?

Ideally I would like to obtain a controller without the need for 'hacking'. If that is necessary are most of the 'knobs' to adjust AC speed controllers just a potentiometer?

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    \$\begingroup\$ This question is really unanswerable without the specifics of the motor type. Additionally questions seeking purchase recommendations are off topic as a matter of policy. \$\endgroup\$ – Chris Stratton Nov 7 '19 at 1:38
  • \$\begingroup\$ Can you help me to respond to your question by suggesting what specifics you need? \$\endgroup\$ – Von-Karmen Nov 7 '19 at 15:55
  • \$\begingroup\$ Again, the question is not answerable without details of the type of motor. Single phase induction motors are basically not speed controllable. Multiphase induction motors can be, but would have required drive electronics to begin with. And brushed universal motors can be. (If you have no idea what you have, induction motors are large and quiet, universal motors are compact and noisy even when spinning without any load - think drill press vs. hand drill) . And also as before, questions seeking recommendation of what you can buy are off-topic here. \$\endgroup\$ – Chris Stratton Nov 7 '19 at 16:59

Single-phase motors are not a good choice for speed control. Triac controllers control the motor voltage. That works reasonably well if the motor is driving a fan or centrifugal pump. Even with fans and pumps, some motor designs are not suitable. With that type of load, the required torque decreases a lot as the speed is reduced. Water or air flow and motor efficiency decreases similarly. There is not much point in operating below 1/3 or 1/4 speed.

For AC motors, it is much better to control frequency. However variable frequency drives (VFDs) don't work particularly well with single-phase motors.

Brushless, permanent-magnet motors are best for very low power requirements.

Choosing between three-phase induction motors and brushless permanent-magnet motors is not easy. They both can provide the performance required for practically any application. Permanent magnet motors are generally more efficient. The price depends on all of the technical requirement details, quantity, location etc.

Triac controllers may require a little work to interface with an Arduino, most others will be easier.


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