- big change to PID class. It was not properly handling the integral.

Essentially it was never large enough to impact the loop. The integral
has been inverted so if you want more integral, define it as a smaller
number.
- added a comment to the config about changing the temp scale

lib/oven.py

@@ -401,15 +401,19 @@ class PID():
         now = datetime.datetime.now()
         timeDelta = (now - self.lastNow).total_seconds()
 
-        window_size = 50
+        window_size = 100
 
         error = float(setpoint - ispoint)
-        self.iterm += (error * timeDelta * self.ki)
-        self.iterm = sorted([-1, self.iterm, 1])[1]
-        dErr = (error - self.lastErr) / timeDelta
 
+        if self.ki > 0:
+            self.iterm += (error * timeDelta * (1/self.ki))
+
+        #self.iterm = sorted([-1, self.iterm, 1])[1]
+        #self.iterm = sorted([-1 * window_size, self.iterm, window_size])[1]
+        #self.iterm = float(self.iterm / window_size) 
+        
+        dErr = (error - self.lastErr) / timeDelta
         output = self.kp * error + self.iterm + self.kd * dErr
-        log.info("pid raw = %f" % (output)) 
         output = sorted([-1 * window_size, output, window_size])[1]
         self.lastErr = error
         self.lastNow = now
@@ -418,6 +422,10 @@ class PID():
         if output < 0:
             output = 0
 
+        #if output > 1:
+        #    output = 1
+
         output = float(output / window_size)
+        log.info("pid=%f p=%f i=%f d=%f" % (output,self.kp * error, self.iterm,self.kd * dErr)) 
 
         return output