PID Controlled Solder Paste Fridge
If you are work on surface mount electronic components here is a nice project.Jeff Keyzer writes:
Solder paste is a little tricky to handle, because most solder paste needs to be refrigerated at 32-50°F to maintain it’s shelf life. Stored at room temp, it tends to get tacky and dry out within a few weeks. Solder paste is also toxic (it contains lead among other things) so it’s not something you want to put in the fridge with your meatloaf.
A proportional–integral–derivative controller (PID controller) is a generic control loop feedback mechanism widely used in industrial control systems. A PID controller attempts to correct the error between a measured process variable and a desired setpoint by calculating and then outputting a corrective action that can adjust the process accordingly.
   PID Controlled Solder Paste Fridge
More detail on PID Controlled Solder Paste Fridge website
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