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the circuit looks good, The RC snubber shpould be connected at the points where the current is switched (at the isolation switch, and on the relays contacts both normally open and normally closed) on the motor a suppression capacitor can be used to reduce EMI. When the limit switch is activated and the relay switches back off the motor will be short-...


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I would recommend starting with a published design. Here's one: https://www.instructables.com/Make-Your-Own-ESC/


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When the brushless DC motors are turned by the force of the fibers, they act as permanent-magnet synchronous AC generators. If they don't need to turn on their own, they can be connected to a rectifier loaded by a resistor with the DC load current modulated by PWM. If the PWM is controlled with feedback from the load cells, that should work. If the motors ...


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The best way to turn a motor with a speed controller on and off repeatedly is to use the controller to do that. A good controller should have an electronic start/start input. If the controller doesn't have that, see if you can command zero speed. It is not the best practice to repeatedly disconnect either the power input to the controller or the power output ...


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If you use a microcontroller, this is a piece of cake. You would just implement a variable PWM drive. To do it with 'a circuit', you'll probably need a transistor with a capacitor on its gate and a couple of resistors. Piece of cake to put together but the downside is during those 5-7 seconds, the transistor will be sinking a lot of power i.e. it'll get hot. ...


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@brhans you are right, it was the EEP pin. On this image I thought the jumper not been soldered, letting EEP unconnected would enable the device, but it was the opposite. Thank you very much @brhans @chris-stratton @fifi-22 @tlfong01


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Update 2020nov18hkt1715 YouTube of DRV8833 Driving a 12VDC GB37 Gear Motor PWM 12.5kHz, 50% Duty Cycle DRV8833 Motor Driver Testing - tlfong01 2920nov18 Update 2020nov18hkt1521 DRV8833 hardware setup for manual jumper signal testing Summary - IN1, IN2 jumper wire signals to (a) 0V, 3V3 and (b) 3V3, 0V to make sure motor moves CCW and CW. Results = OK. ...


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Welcome to StackExchange! Well done first post. You are correct, your forcing voltage is out of phase with your motor. Looks to me like you are sampling in the incorrect location during your PWM cycle. Ensure that your ADC sample occurs at the center of the PWM cycle when the PWM cycle is high. There may be a minimum duty cycle required in order to get a ...


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The issue with controlling ONLY the voltage is mostly of torque and load. An AC asynchronous motor will lose torque proportional to the voltage reduction, but also lose PEAK torque at the SQUARE of the voltage reduction. Peak torque, typically around 200% of Full Load Torque, is what the motor utilizes to maintain speed as load changes. So if you cut that ...


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Those are 6V motors, I think (please check). You are feeding the motor shield with 4.8V, and the L293D will drop the voltage the motor sees by 1.4V to 1.8V, so you end up with only 3 to 3.4V across the motor. Using 4 primary cells of 1.5V each, or 5 cells of 1.2V each, should show some improvement, and yes, so would a more efficient motor driver. You can ...


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The internal diode won't matter if the circuit has external diodes. Never operate a IGBT at more than it's maximum gate-emitter voltage or collector-emitter voltage or it will blow. These two ratings are the most absolute and the easiest to understand. Collector-emitter Saturation voltage is next important and determines the voltage across the IGBT when ...


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Fuses Fuses are used as a last resort measure to prevent fires. They should be able do completely disconnect the circuit. Pay some respect to fuses and Don't shunt them with anything. Your design should not rely on the fuse blowing at some point in order to work correctly. The relay (contactor) I think you should not expect the contactor to disconnect in ...


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