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Are temp swings of 20f ok?


FrankS

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3 minutes ago, Smokin Monkey said:

Hi Frank, Welcome to the Forum.

10’C swing is not the best, but 5’C each side is not bad.

Just a test, have you ever tested your domestic Oven, to see what variation it has.

Oven? Is that the thing the mrs uses in the kitchen?

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1 minute ago, Smokin Monkey said:

Yes, next to fridge near the sink! ?

We all get preoccupied with our Pits running to an exact temperature.

But one thought, is how your Q-Lite is set up.

Will find link to Wangs (designer) site to show what the best parameters are.

that would be great!

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41 minutes ago, Smokin Monkey said:

Take a look at this thread, settings are near the bottom of page. 

http://www.woodsmokeforum.uk/topic/148-qmaster-lite-atc-thoughts-and-opinions/?tab=comments#comment-396

Have you any idea what these mean?

P= Proportional Value. Setting 30 Seconds

I= Integeral Value. Setting 240 Seconds 

D= Derivative Value. Setting 60 Seconds 

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Ok, it’s how quick it looks at what’s happening and reacts. It is self learning.

This is the definition.

  • Term P is proportional to the current value of the SP − PV error e(t). For example, if the error is large and positive, the control output will be proportionately large and positive, taking into account the gain factor "K". Using proportional control alone in a process with compensation such as temperature control, will result in an error between the setpoint and the actual process value, because it requires an error to generate the proportional response. If there is no error, there is no corrective response.[1]
  • Term I accounts for past values of the SP − PV error and integrates them over time to produce the I term. For example, if there is a residual SP − PV error after the application of proportional control, the integral term seeks to eliminate the residual error by adding a control effect due to the historic cumulative value of the error. When the error is eliminated, the integral term will cease to grow. This will result in the proportional effect diminishing as the error decreases, but this is compensated for by the growing integral effect.
  • Term D is a best estimate of the future trend of the SP − PV error, based on its current rate of change. It is sometimes called "anticipatory control", as it is effectively seeking to reduce the effect of the SP − PV error by exerting a control influence generated by the rate of error change. The more rapid the change, the greater the controlling or dampening effect.[2].

 

Sounds very daunting, but it’s getting a balance between all three that gives a smooth temperature control.

Too close and its erratic, too wide and high temperature fluctuations.

Hope this helps?! ?

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1 minute ago, Smokin Monkey said:

Ok, it’s how quick it looks at what’s happening and reacts. It is self learning.

This is the definition.

  • Term P is proportional to the current value of the SP − PV error e(t). For example, if the error is large and positive, the control output will be proportionately large and positive, taking into account the gain factor "K". Using proportional control alone in a process with compensation such as temperature control, will result in an error between the setpoint and the actual process value, because it requires an error to generate the proportional response. If there is no error, there is no corrective response.[1]
  • Term I accounts for past values of the SP − PV error and integrates them over time to produce the I term. For example, if there is a residual SP − PV error after the application of proportional control, the integral term seeks to eliminate the residual error by adding a control effect due to the historic cumulative value of the error. When the error is eliminated, the integral term will cease to grow. This will result in the proportional effect diminishing as the error decreases, but this is compensated for by the growing integral effect.
  • Term D is a best estimate of the future trend of the SP − PV error, based on its current rate of change. It is sometimes called "anticipatory control", as it is effectively seeking to reduce the effect of the SP − PV error by exerting a control influence generated by the rate of error change. The more rapid the change, the greater the controlling or dampening effect.[2].

 

Sounds very daunting, but it’s getting a balance between all three that gives a smooth temperature control.

Too close and its erratic, too wide and high temperature fluctuations.

Hope this helps?! ?

:O

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