[Homeroast] variable transformers

Rich rich-mail at octoxol.com
Tue Feb 28 22:43:05 CST 2012


Ray, now you have gone and spoiled all the fun. ;)

On 02/28/2012 07:24 PM, raymanowen at gmail.com wrote:
> KISS- Do Not, rpt, NOT control temperature of a heat process by varying the
> power applied to the electric heater. Skipping all the details, just run
> the heating device at Full Power- 100%, or whatever you can get with the
> available power.
>
> Instead of trying to control temperature by varying the line potential and
> heater current, just control the low power drawn by the air mover.(fan
> motor)  Low air flow through a heating device or Corvair engine causes the
> air stream to get hotter and the engine to cook a couple dozen O-ring oil
> seals after the fan belt flips.
>
> SCR, Triac/ diac dimmers are extremely non-linear devices and resistive
> heaters respond exponentially to applied potential changes. Kiss
> temperature control goodbye.



More information about the Homeroast mailing list