Large Scale Central

H Bridge for Tortoise

In case the information is useful to anyone: I picked up one of these cheap Chinese H Bridge boards to try it out with a Tortoise switch machine. I want to be able to control my (indoor) switches with a microntroller. It works great.

https://www.ebay.com/itm/New-L298N-DC-Stepper-Motor-Driver-Module-Dual-H-Bridge-Control-Board-for-Arduino/191674305541?epid=837340831&hash=item2ca0adcc05:g:Jb0AAOSwESNZ7v2s

So zactly what is the difference between an H Bridge motor controller and an Electronic Speed control (ESC) ? I’ve done some recent experiments with a real cheap ESC and want to try something better. I know the bridge you are referencing is driven by an Audrino and is designed for stepper motors, but I have also seen them advertised for standard motors driven by an RC Servo output which is how I would use it.

The H bridge itself simply provides control over the polarity of its output. For the tortoise motor, the polarity determines the direction of travel. I am not doing any kind of speed control, since it’s already quite slow.

Most ESCs designed for RC applications translate a servo signal to a 0% -100% duty cycle PWM output. They integrate an H bridge for directional control. If you were to drive an H Bridge directly with a servo signal, the DC motor would never turn off or reach 100%, as the minimum pulse width for a servo is 1 ms and the maximum is 2 ms, at 50 Hz. The board that I linked above expects a raw PWM signal. In my case, I am just sending it a logic signal (essentially 100% duty cycle).

Thanks - I guess my terminology hasn’t caught up with my idea factory. What I was calling simply an H-Bridge is really a “Single channel H-bridge speed controller - 10A, 6.5V to 28V” So I are now a bit more edumacated. Thanks!

H bridge is really the design, where the schematic looks like an “H”, although you can buy an IC that has an H bridge circuit inside.