The drivers used in 3D printers are constant current drivers. As long as the supply voltage is high enough, the motor will get the current that you set. If you connect the moors in parallel, they share the current.
In your example, you have steppers that are rated at 1A and have a phase resistance of 2.5 ohms. You want to run them at 1A peak current (in practice you would normally run them at a lower current).
- If you connect them in parallel, set the driver to 2A. Each motor phase will get 0 to 1A (depending on the microstep position) and the voltage drop across the parallel pair of windings at standstill will be 0 to 2.5V.
- If you connect them in series, set the driver to 1A. Each motor phase will get 0 to 1A (depending on the microstep position) and the voltage drop across the series pair of windings at standstill will be 0 to 5V.
The main differences between the two configurations is:
- In the parallel configuration, the driver will run much hotter because it will be dissipating more than 4x the power, because of the higher current
- In the series configuration, the speed at which torque starts to drop will be 50% lower than for the parallel configuration. This is because the higher the speed, the more voltage is needed to force the current through the windings. Eventually the voltage needed becomes higher than the driver supply voltage, so the full current can no longer be maintained. There is a motor EMF calculator at [reprapfirmware.org] to help you estimate this speed.
In your example, you have steppers that are rated at 1A and have a phase resistance of 2.5 ohms. You want to run them at 1A peak current (in practice you would normally run them at a lower current).
- If you connect them in parallel, set the driver to 2A. Each motor phase will get 0 to 1A (depending on the microstep position) and the voltage drop across the parallel pair of windings at standstill will be 0 to 2.5V.
- If you connect them in series, set the driver to 1A. Each motor phase will get 0 to 1A (depending on the microstep position) and the voltage drop across the series pair of windings at standstill will be 0 to 5V.
The main differences between the two configurations is:
- In the parallel configuration, the driver will run much hotter because it will be dissipating more than 4x the power, because of the higher current
- In the series configuration, the speed at which torque starts to drop will be 50% lower than for the parallel configuration. This is because the higher the speed, the more voltage is needed to force the current through the windings. Eventually the voltage needed becomes higher than the driver supply voltage, so the full current can no longer be maintained. There is a motor EMF calculator at [reprapfirmware.org] to help you estimate this speed.