Flyingbear P905 Power Relay Box

thingiverse

I recently bought a Flyingbear P905 printer. I really like the printer it prints very decent quality and is good value for money. However there are a few things I have become accustomed to which I really miss on my new printer. I like to be able to have octoprint automatically shut down the printer after a period of time of inactivity. using a 5V relay module on PS_ON header makes this possible. I designed this box to allow easy installation onto the frame with no customization requirement. You can install this on a factory default P905 and do not need to move any components or drill any holes in the frame. My P905 came with a MKS Gen_L controller board, this board does not have a PS_ON header which allows you to control the relay using M80/M81. It is however possible to use the servo headers for switching power, to accomplish this you will need to tweak your firmware. I simply changed the PIN assignment for SERVO0_PIN to 12 and PS_ON_PIN to 11 in the pins_RAMPS.h file. Then you can use the first servo connector to switch the relay. Lastly you will have to update your Configuration.h to enable the POWER_SUPPLY setting. The relay simply switches the Live wire to the power supply on or off. I also connected a switch on the top of the box in parallel which allows to bypass the relay and keep the printer on if so desired. Hope you enjoy this upgrade.