How to Resurrection for 3D printers March 15, 2018 10:07PM |
Registered: 6 years ago Posts: 3 |
Re: How to Resurrection for 3D printers March 16, 2018 03:11AM |
Registered: 10 years ago Posts: 14,672 |
Re: How to Resurrection for 3D printers March 28, 2018 11:32PM |
Registered: 6 years ago Posts: 3 |
Quote
dc42
The Duet WiFi and Duet Ethernet controller electronics running RepRapFirmware have this resurrect facility too (https://duet3d.dozuki.com/Wiki/Setting_up_to_resume_a_print_after_a_power_failure). The hardware you need is:
- A mechanism to detect that power is going down. The Duets have this built in. The Prusa uses a separate power detect board that feeds a signal into the main electronics.
- 24V power not 12V, so that sufficient voltage is available to drive the motors for longer.
- A mechanism to turn off the heaters quickly when power failure is detected, to conserve power. The Duets are fast enough to do this in firmware. The processors used in 8-bit electronics are slower and don't provide configurable interrupt priorities, so Prusa has extra circuitry included on the Einsy controller to do that.
- If you save the resume data to SD card, you may need a mechanism to continue to provide power to the processor for several tens of milliseconds after the main power is exhausted. Again, this is built in to the Duet. I don't know whether the Einsy has this too. A large capacitor connected across the processor power rail may be sufficient.