3D Printer Shutdown Timer, Auto Off Switch

thingiverse

I needed an easy-to-use addon module that could shut off my printer after it finished a print but also wait for a while to let it cool down with fans running before turning it off so I came up with this. Most of the time when I do long multi-hour prints I will start them before bed and let them run through the night, but the problem is sometimes I might not be up by the time they're done printing for six hours or more, and I don't want my printer to sit idle for a few hours or all day if I leave the house. So here's what I came up with - it's an FRM01 Timer Relay Delay Module that I picked up from eBay, but I couldn't find it anywhere else online so I'll link to the seller I bought mine from instead. http://www.ebay.com/itm/DC-5V-12V-24V-Multifunction-Self-lock-Relay-PLC-Cycle-Delay-Timer-Control/321964813492?_trksid=p2060778.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT This module comes with two screw terminals and one set of three screwdriver drivers. The instructions tell me to attach the terminals on the top part of the board using the two screwdrivers, which should give a strong connection for easy plug in - then just insert my printer cable into the plug, making sure it's fully seated. http://www.ebay.com/itm/281124299886?_trksid=p2060778.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT There are several different modules available, so be sure to read the specifications and reviews before buying. Some may have different features like an adjustable time delay or different voltage outputs. But generally they all work similarly - when my printer is off the timer won't count down and it'll just stay idle, waiting for a manual input or signal to continue running. On my specific FRM01 Timer Relay Delay Module there's only one input terminal but two output terminals that I've used to power both of the switches needed to activate it, which are normally closed single pole double throw microswitches. http://www.ebay.com/itm/281124299886?_trksid=p2060778.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT I used two separate switches to control it - one that controls power to the entire circuit and a bypass switch. When I flip both switches on my printer starts up, when I start a print but want it to auto-shutoff later with delay i just flip off the bypass switch and wait until the bed is lowered then I turn on the printer and set off for work. To build this system you will need: * The FRM01 Timer Relay Delay Module * Two 24V DC power supply * Two single pole double throw (SPDT) normally closed (NC) microswitches You'll also want some wire to connect all of these components together. This system will turn off your printer after a set delay period with just one press of a switch and turn back on when you're ready again. For the power switch I used a small toggle switch that can handle 10A. To connect it to the module simply strip the insulation from both ends, push them onto the terminal and make sure they are securely attached using wire nuts.