This is a simple bed temperature mod for the Up! Mini 3d Printer. You can switch between 60degC and 100degC. A red LED will show you when the bed is powered up and a green led will lights up when the selected temperature is reached. This can be very useful for Up! Mini as you don't have any bed temperature control from the software.
Just use a second temp controller for 100decC, connected in parallel with the original one through a switch. The two LEDs are connected through 3.3K resitors (the bed is powered at ~18Vcc). The red one is connected directly to the bed power connector, the green one in parallel with the 60degC controller. The wires are with silicon insulator in order to be able to work at high temperature without melting. The switch is fixed on the bed with epoxy (Poxipol), able to handle 100degC,