If the battery is the heart of a scooter, the controller will be considered the brain. All electrical functions go through this little (mostly silver) box. It is commonly located inside the deck of the scooter, just beside the battery. The controller also limits the amount of power that can be "pumped" into the motor and cuts off the power supply if it detects a preset low battery voltage. This is to protect the battery from getting damaged, similar to what a BMS (Battery Management System) does.
Below you will find an image of a typical controller, it's functions and specifications. Some functions are common, others not so much.
Choosing a controller
First of all, every controller comes with different types of connectors. There is no real standard but some connectors are more common than others. When choosing a controller there are a few parameters you need to consider. Namely:
- Voltage (V): The controllers voltage range must match the rated voltage of your battery
- Ampere (A): The maximum current the controller will allow to get through to the motor
- Wattage (W): Multiply V x A if not stated. As a rule of thumb, this figure should be double the rated wattage of your motor
- Hall Sensor: Controllers with hall sensor wires commonly do not work with motors that do not have hall sensors but it works vice versa.
- Motor Phase: Connect your motor phase cables here (usually 3 thick wires)
- Ignition On/Off: Connect a switch or key lock here
- Battery: Connect your battery here (usually 2 thick wires, red/black)
- Hall Sensor: Connect your motor hall sensor cables here (usually 5-6 thin wires)
- Cruise Control: Automatically maintains throttle output (connect a jumper to enable)
- Throttle: Connect your throttle here (usually 3 thin wires, red/black/white)
- Self Learning: To learn the motors hall sensor configuration. Connect on first run of the controller, disconnect once the motor runs properly
- Battery Indicator: Connect voltmeter or battery LEDs here
- Reverse: Uncommon function. Connect 2 way switch here to select forward/reverse
- Pedal Assist (PAS): For electric bicycles only. Connect your pedal assist sensor here.
- LCD/Display: Connect your LCD here. Many controllers do not work if not connected. Install a jumper if you do not have an LCD (check jumper configuration with supplier)
- Motor Brake: To automatically cut power to the motor when braking. Connect brake lever switches here.
- Speed Control: Connect switch here to select speed mode (3 are common)
- High/Low Brake Level: To enable motor braking (direct drive motors only). 'Low' provides a low amount of braking force and 'High' provides a high amount of braking force. Either one could be used depending on the amount of braking force you would like to have.