Canning Appliance

Recently I toured a farm’s harvest processing facilities and mentioned to the farmer that I thought I could automate one of his processes. He challenged me to build such an appliance, so I did.

Using a commercial 1500W hotplate and an Omega temperature controller I fabricated the appliance shown below. A Solid State Relay (SSR) switches power to the hotplate to modulate temperature. The controller operates in four modes (temperature display, constant temperature and ramp/soak program, PID). Since the hot plate operates only in on/off mode I couldn’t use the PID (Proportional Integral Differential) mode.

Front view testing
Front view testing

 

 

 

 

 

 

Top View
Top View

 

 

 

 

 

 

More Testing
More Testing

 

 

 

 

 

 

 

 

Wiring in Bottom
Wiring in Bottom

 

 

 

 

 

 

After using my canning appliance, the happy farmer reported that he was able to control temperature within a +/- 3F range. And this resulted in shortened process times and more uniform product.

Download Design Docs in PDF Format