The Best Speed Controller for 775 Motor | How to Make 12V Controller at Home
In this video we are going to make Best Speed Controller for 775 Motor | How to Make 12V Controller at Home
You can make this Speed Controller Easily at Home.
Instructions About Z44n Mosfit:
It's known for its capacity to switch high voltage and current levels. MOSFET means Metal Oxide Semiconductor Field Effect Transistor, a transistor type that has low resistance to output and high resistance to input. The IRFZ44N can handle a maximum voltage of 55 volts and a maximum current of 49 amperes.
To control a large motor's speed, you need a motor controller. There are a range of motor controllers available on the market to deal with motors up to about 50A, but there are only a small handful capable of dealing with very high current electric motors (over 50A). Over the course of this lesson we are going to explore four different motor controllers, and review how to use them. By the end of this lesson you should be more than confident to power up a brushed DC motor of nearly any (reasonably sane) size and control its speed, with or without an Arduino board.
The easiest way to control a relatively low current 12-24V motor is by using a generic analog DC motor speed controller. This type of controller has a potentiometer to vary the speed of the motor. These controllers can be found with a wide range of power ratings. However, this type of controller is typically best for motors in the 5A to 20A range. For this example I selected a speed controller rated at 30A. The reason for this is the largest motor I am looking to control has a stall current no more than 15A, and it is advisable to get a controller rated for twice as much as your motor's typical operating current.
This type of generic speed controller is best when you want an easy solution that is pre-made and can manually control (with a knob) the speed of the motor in one direction. The shortcoming of this type of controller is that they are typically unable to reverse the motor direction, and not suitable for microcontroller control.
To wire up a DC speed controller, you connect the motor power cables to the motor screw terminals on the controller, and the battery wires to appropriate battery screw terminals on the controller. Be mindful the wires are being gripped firmly and none of the wire strands have become loose and are sticking out.
Once the wires are attached, close the case back up. There is potential high current and high heat on the circuit board. The enclosure will prevent shocks, burns and electrical shorts.
To control the motor simply turn the knob. If everything is wired correctly, your motor's speed should begin to ramp up as the knob is turned clockwise. As you will notice, with this type of controller, your motor will only ever rotate in one direction.
Wiring up a wheelchair motor to a DC speed controller is a little bit different because of the electronic brake attached to the back of the motor. In normal wheelchair operation, the brake is a fail safe to prevent the wheelchair from moving when it is not powered. So, if something goes wrong and the brake is not energized with 24V by the wheelchair control circuit, the wheelchair motor won't spin.
This can result in catastrophe when using standard (non-wheelchair) controllers. If you power the motor without releasing the brake, you will stall the motor (keep it from spinning) and force the wheelchair motor to draw its maximum current. The reason for this is that the motor is fighting against the brake as hard as it can try to spin, and will draw as much current as it is able while doing so. If this happens, there is a chance you will overwhelm and eventually fry the motor controller and release its magic smoke!
If you keep the electronic brake installed, it is important to connect the brake wires directly to the battery terminals. In the example above, two green wires were used to extend the two white brake wires (so they are easier to see) and attached to the battery bank. One wire has a switch connected in series with it so that the brake can be toggled on and off. If it is attached without a switch, the electromagnet inside the brake will eventually drain the batteries. The switch must be turned on before the motor's speed is adjusted using the controller.
A better solution for connecting a wheelchair motor to this (or any) motor controller is to remove the brake from the motor altogether. Fortunately for you, I have posted detailed instructions for removing an electric brake from a wheelchair motor. Once the brake is removed, you can simply connect it to the controller as you would any other DC motor.
To control the speed of larger motor using an Arduino, you would need a motor controller board.
Many motor controller boards that interface with microcontrollers are H-bridge based, such as the Parallax DHB-10 and Cytron MD30C controllers. This is a special type of circuit that allows you to reverse thevoltage polarity of a motor's power supply. This, in turn, changes the motor direction. You can learn more about H-bridges in the Motors and Motion Lesson of my Robotics Class, and see it in action in the Reversing a Motor lesson of this class.
However, when you begin controlling motors of 100A or greater, these boards are typically only designed to control speed, and not reverse direction, such as the Alltrax 48300 controller. These types of controllers are typically used in electric vehicles which use external circuitry to reverse motor direction.
The Parallax DHB-10 Dual H-Bridge 10 Amp Motor Controller is good for controlling motors with a stall current of around 5A, such as the MY68 DC motor. This circuit board can control motors with a power supply of up to 24V and handle currents up to 10A continuous and brief surge current up to 12A. However, you shouldn't plan on running a motor with a 10A stall current off of this board. As already mentioned, it is wise to get a motor controller that is rated for double the motor's stall current.
Also note that there is a 20A fuse on this board. Even though a single channel can theoretically handle a 12A surge, if you were to connect two motors, and have power surges of 12A on both channels at once, it could potentially blow the safety fuse.
To control the motors, we need to connect the motor to the 10A motor 1 terminal. This is the green terminal with the set screw helpfully labeled "Motor 1." If we had an additional motor, we could also connect it to “Motor 2.”
Once the motor is connected, connect the power supply to the terminal labeled “6-24V VIN.” In case it was not clear, VIN stands for voltage-in. For this demonstration I am using a 12V 6Ah battery.
The next order of business is to connect a microcontroller to the motor controller board. This controller board can be controlled like a servo motor. Therefore, it should not be surprising that we need to plug a servo extension cable into the Channel 1 header pin inputs (labeled “Ch1”), with the black, red and white wires lining up appropriately (“WRB” - as labeled).
Using hookup wire, the white wire from the servo extension cable should then be connected to Digital Pin 9, and the black wire with the Arduino's ground pin. The red wire can be ignored.
The Best Speed Controller for 775 Motor | How to Make 12V Controller at Home
In this video we are going to make Best Speed Controller for 775 Motor | How to Make 12V Controller at Home
You can make this Speed Controller Easily at Home.
Instructions About Z44n Mosfit:
It's known for its capacity to switch high voltage and current levels. MOSFET means Metal Oxide Semiconductor Field Effect Transistor, a transistor type that has low resistance to output and high resistance to input. The IRFZ44N can handle a maximum voltage of 55 volts and a maximum current of 49 amperes.
To control a large motor's speed, you need a motor controller. There are a range of motor controllers available on the market to deal with motors up to about 50A, but there are only a small handful capable of dealing with very high current electric motors (over 50A). Over the course of this lesson we are going to explore four different motor controllers, and review how to use them. By the end of this lesson you should be more than confident to power up a brushed DC motor of nearly any (reasonably sane) size and control its speed, with or without an Arduino board.
The easiest way to control a relatively low current 12-24V motor is by using a generic analog DC motor speed controller. This type of controller has a potentiometer to vary the speed of the motor. These controllers can be found with a wide range of power ratings. However, this type of controller is typically best for motors in the 5A to 20A range. For this example I selected a speed controller rated at 30A. The reason for this is the largest motor I am looking to control has a stall current no more than 15A, and it is advisable to get a controller rated for twice as much as your motor's typical operating current.
This type of generic speed controller is best when you want an easy solution that is pre-made and can manually control (with a knob) the speed of the motor in one direction. The shortcoming of this type of controller is that they are typically unable to reverse the motor direction, and not suitable for microcontroller control.
To wire up a DC speed controller, you connect the motor power cables to the motor screw terminals on the controller, and the battery wires to appropriate battery screw terminals on the controller. Be mindful the wires are being gripped firmly and none of the wire strands have become loose and are sticking out.
Once the wires are attached, close the case back up. There is potential high current and high heat on the circuit board. The enclosure will prevent shocks, burns and electrical shorts.
To control the motor simply turn the knob. If everything is wired correctly, your motor's speed should begin to ramp up as the knob is turned clockwise. As you will notice, with this type of controller, your motor will only ever rotate in one direction.
Wiring up a wheelchair motor to a DC speed controller is a little bit different because of the electronic brake attached to the back of the motor. In normal wheelchair operation, the brake is a fail safe to prevent the wheelchair from moving when it is not powered. So, if something goes wrong and the brake is not energized with 24V by the wheelchair control circuit, the wheelchair motor won't spin.
This can result in catastrophe when using standard (non-wheelchair) controllers. If you power the motor without releasing the brake, you will stall the motor (keep it from spinning) and force the wheelchair motor to draw its maximum current. The reason for this is that the motor is fighting against the brake as hard as it can try to spin, and will draw as much current as it is able while doing so. If this happens, there is a chance you will overwhelm and eventually fry the motor controller and release its magic smoke!
If you keep the electronic brake installed, it is important to connect the brake wires directly to the battery terminals. In the example above, two green wires were used to extend the two white brake wires (so they are easier to see) and attached to the battery bank. One wire has a switch connected in series with it so that the brake can be toggled on and off. If it is attached without a switch, the electromagnet inside the brake will eventually drain the batteries. The switch must be turned on before the motor's speed is adjusted using the controller.
A better solution for connecting a wheelchair motor to this (or any) motor controller is to remove the brake from the motor altogether. Fortunately for you, I have posted detailed instructions for removing an electric brake from a wheelchair motor. Once the brake is removed, you can simply connect it to the controller as you would any other DC motor.
To control the speed of larger motor using an Arduino, you would need a motor controller board.
Many motor controller boards that interface with microcontrollers are H-bridge based, such as the Parallax DHB-10 and Cytron MD30C controllers. This is a special type of circuit that allows you to reverse thevoltage polarity of a motor's power supply. This, in turn, changes the motor direction. You can learn more about H-bridges in the Motors and Motion Lesson of my Robotics Class, and see it in action in the Reversing a Motor lesson of this class.
However, when you begin controlling motors of 100A or greater, these boards are typically only designed to control speed, and not reverse direction, such as the Alltrax 48300 controller. These types of controllers are typically used in electric vehicles which use external circuitry to reverse motor direction.
The Parallax DHB-10 Dual H-Bridge 10 Amp Motor Controller is good for controlling motors with a stall current of around 5A, such as the MY68 DC motor. This circuit board can control motors with a power supply of up to 24V and handle currents up to 10A continuous and brief surge current up to 12A. However, you shouldn't plan on running a motor with a 10A stall current off of this board. As already mentioned, it is wise to get a motor controller that is rated for double the motor's stall current.
Also note that there is a 20A fuse on this board. Even though a single channel can theoretically handle a 12A surge, if you were to connect two motors, and have power surges of 12A on both channels at once, it could potentially blow the safety fuse.
To control the motors, we need to connect the motor to the 10A motor 1 terminal. This is the green terminal with the set screw helpfully labeled "Motor 1." If we had an additional motor, we could also connect it to “Motor 2.”
Once the motor is connected, connect the power supply to the terminal labeled “6-24V VIN.” In case it was not clear, VIN stands for voltage-in. For this demonstration I am using a 12V 6Ah battery.
The next order of business is to connect a microcontroller to the motor controller board. This controller board can be controlled like a servo motor. Therefore, it should not be surprising that we need to plug a servo extension cable into the Channel 1 header pin inputs (labeled “Ch1”), with the black, red and white wires lining up appropriately (“WRB” - as labeled).
Using hookup wire, the white wire from the servo extension cable should then be connected to Digital Pin 9, and the black wire with the Arduino's ground pin. The red wire can be ignored.
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