Rough design to control Easycook or Flavorwave glass bowled fan forced
oven for drying meat.

Welcome any comments on the following setup.



Constant ambient temperature for drying is  58 DegC for 4 - 6 hours
(after initial ramp of of meat temperature to 72 degrees C).

K type Thermocouple sampled by max6675 connected to a pic16f887.

Temperature constantly averaged over the last 8 samples.

PIC controls TRIAC BT137 via opto MOC3020. TRAIC controls heater
element.  Fan always on.

E -> error
SP -> Set Point in Degrees C
A -> Average sampled temperature in degrees C
M -> Mark in Mark/Space ratio.  The number of Heater On time units out
of a maximum of 255 time units.  255 time units approx 10 secs.
P -> Proportional multiplier.
O -> output heater on.


pseudo code
A =3D Initial Sample eg 24 degree C
SP =3D 58
P =3D 8

loop:

E =3D SP - A

if E < 0
    E =3D 0

M =3D E * P

if M > 255 then
     M =3D 255

For i =3D 0 to 255
     if (i < M)  then
            O =3D ON
     else
             O =3D 0FF
     end
     delay 10/255 Seconds
     sample and average

Next i

goto loop
--=20
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