Here are the pics, first up we have pictures of the two variants of the RAMPS board, one of which you will receive with your SumPod. They are electrically identical:
Mounted in the Arduino Mega 1280 dev board:
With the full complement of five A3983 stepper driver boards for the dual feeder based system:
The overall board stack looks like this:
When mounting the stepper drivers ensure they are orientated correctly. To help this legend on the underside of the driver PCBs indicate the pin function matching the legend on the RAMPS board.
Uprated PSU and Improved Stepper Performance
Currently the SumPod uses a 12VDC supply. I am intending to use a higher voltage supply (24VDC) because superior stepper performance is possible, and besides the driver boards will run at voltages of up to 35VDC.
Since the SumPod comes with high torque (44Ncm) hybrid steppers using the chopper current limiting stepper drivers, greater speed is possible with a higher voltage. This is because of the natural low pass filtering that occurs with an inductor (stepper coil). As frequency of pulses increases the amount the stepper coil energises (directly affecting torque) reduces. Increasing the voltage proportionally improves energisation rates and hence top speed.
I realise the Mega 1280 board supports a maximum input voltage of 12V and I intend to use a DC-DC step down converter to provide an acceptable supply.
I haven't yet connected the LCD, but here are some pics and technical details:
Until next time
SumPod Guniea Pig