If you bought all the parts new, it would cost you about $30 to make. Depending on where you live, it might take a couple of years to get that back, but your comfort level will be greatly improved. The circuit can be made to be much more precise if needed. I'd replace the SCR power supply with a zener diode circuit or added an electronic regulator. This would only be needed if you used the thermal air pump to pull air through the box. If you used an isolated 24 volt power supply, the temp sensor could be brought outside the box, eliminating the need for the thermal air pump and any kind of regulated power supply.
Clever design, Andrew. Congrats. I'm curious about the cost of this compared to conventional technology. Is the cost higher? Are there some applications that would need this extra precision at any cost?
Using wireless chips and accessories, engineers can now extract data from the unlikeliest of places -- pumps, motors, bridges, conveyors, refineries, cooling towers, parking garages, down-hole drills and just about anything else that can benefit from monitoring.
With strong marketplace demand for qualified engineers across the board that currently outstrips the available supply, there may never be a better time for engineers and project managers to advance their careers and salaries. Whether those moves are successful in the short-term and long-term is likely to depend on how the transition from one job to the next is handled.
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