More integration testing

A project log for Small Programmable Kiln

A small kiln with big expectations: Fusing PMC, Solder PCBs, Harden/Temper/Anneal/Carburize Steel, Pottery, Glass, Melting Precious Metals

myburamybura 05/03/2020 at 10:380 Comments

Tweaked PID controller to stabilize target swings. Still needs further tweaking, maybe even adding Auto Tune as the oven behaves differently at different temperatures. Increased the PWM from 25% max to 100% max to do a full load test.

Wrapped most of the oven in foil, shiny side inward. Made a big difference to perceived heat emission and it completely blinded the laser temp sensor (was reading room temp all over the surface)

Ran up to 800C to check the thermal stability of everything hooked up. Some findings:

Overall the construction seems sound enough and electronics/electrics can handle the design well.

Think there is a massive loss to convection caused by the gaps between bricks. Also noticed the max power the coils are willing to draw peaked at about 1650W suggesting a 3rd coil might be needed to reduce the resistance. Trying to keep the max current consumption under 10A to avoid needing a special wall socket.

Some other random notes:

Next potential steps: