OT Driving a bigger motor and heater

[garyhlucas]

I am not much of an electronics guy, some of you guys are. I am looking at building a plastic extruder, like a 3D printer head, where I need to control a DC motor and a heating element. I want to use an Adafruit feather and motor controller board. The motor controller has 4 H bridges with 1.2 amp at 12vdc max output. Can H bridges be paralleled for higher current? Can the output from an H bridge simply drive larger power transistors to run a larger motor? The heater is about 500 watts. Thinking of SSR to switch the AC power for the heaters.

[Tobias-B]

A. Can H bridges be paralleled for higher current?
B. Can the output from an H bridge simply drive larger power transistors to run a larger motor?.

A. not typically recommended. It depends on the type of device used for the current drive.

B. Yes, but the easy way would be to have the Feather drive a larger controller.
For the heater, the Feather can drive a SSR directly,
and for the motor drive, there are LOTS of larger options.
They'll have circuitry in them to protect themselves,
which standalone devices won't have.

t

[psomero]

Do you need to control the speed of the motor or is it supposed to be fixed? I would not bother with trying to parallel h-bridges or using them as gate drivers for bigger transistors (I'd use mosfets). I would reckon the small h-bridges on the feather board won't respond well to the heat from sharing current even if it were possible. Is it the TB6612 board? It does not like overcurrent, I can confirm from experience with a big stepper motor.

Since it's a dc.motor you can power it directly with a dc power supply. Adjust the voltage to modulate the speed.

[garyhlucas]

Thanks for the advice. I need variable speed and it needs to be very compact. I'll look elsewhere.