PID Heater Control

Started by rickman in sci.electronics.design2 years ago 47 replies
PID

If a heater is controlled by turning it on and off, does a PID algorithm help in more closely controlling the temperature? Will running the...

If a heater is controlled by turning it on and off, does a PID algorithm help in more closely controlling the temperature? Will running the PID loop faster than the temperature measurement improve anything? How would a PID control be an improvement over a simple temperature comparison with or without an anticipator? -- Rick


Video on tuning PID controllers

Started by Tim Wescott in sci.electronics.design1 year ago 20 replies
PID

Yet another video on tuning PID controllers has been tossed into the YouTube pool. ? https://youtu.be/drYO60z6_h4 -- Tim...

Yet another video on tuning PID controllers has been tossed into the YouTube pool. ? https://youtu.be/drYO60z6_h4 -- Tim Wescott Wescott Design Services http://www.wescottdesign.com I'm looking for work -- see my website!


PID Control programming Questions

Started by RogerN in sci.electronics.design4 years ago 12 replies
PID

I have a program being ran every 20 milliseconds and I'm trying to implement PID control. So P = SetPoint - Actual, I = I + P ? , and D = P -...

I have a program being ran every 20 milliseconds and I'm trying to implement PID control. So P = SetPoint - Actual, I = I + P ? , and D = P - Old_P???? On D, should "Old_P" be from the previous round or should it be a value from a certain length of time ago? Also, is "I" just summed up or is it the sum of I over a certain length of time? I'm trying to find out if I need to set up a...


Fincor PID dancer schematic or Manual needed

Started by M Philbrook in sci.electronics.design2 days ago

I know many of your old farts here have a collection of schematics or at least manuals.... I can not find the manual or maybe even the...

I know many of your old farts here have a collection of schematics or at least manuals.... I can not find the manual or maybe even the schematic that sometimes comes with these manuals for a : Fincor 105456401 , 1900-77 This is a PID dancer controller with a tach following option. If need be I can reverse engineer one using TinyCad or some common free electronic ...


How about it? Experiments of the third kind , take 999999.

Started by Jan Panteltje in sci.electronics.design6 years ago

How about it? Experiments of the third kind , take 999999. Update Testing the temperature controller There has been some talk about PID...

How about it? Experiments of the third kind , take 999999. Update Testing the temperature controller There has been some talk about PID controllers to keep temperature constant. And I wanted to keep the 'D' out of the PID. After the melted box experiment (see early postings on this subject), I had some idea of the amount of power needed to keep the box with sensors at about 40C, and fr...


numerical methods for calculating PID equivalent functions

Started by Jamie M in sci.electronics.design3 years ago 27 replies
PID

Hi, Can a partial differential equation be numerically calculated to give a function that is equivalent to a PID loop for controlling a...

Hi, Can a partial differential equation be numerically calculated to give a function that is equivalent to a PID loop for controlling a multivariable system (ie a lunar lander with yaw/pitch/thrust to land on a given X/Y coordinate from a given altitude)? Do partial differential equation solvers ie for the heat equation, also work for large numbers of variables, ie 10? Is this method ...


PI/PID controllers and tuning

Started by George Herold in sci.electronics.design6 years ago 2 replies
PID

Hi guys/gals. A bit of a problem has caused me to revisit PID/ PI controll= ers and tuning. I have this nice paper on the Ziegler=96Nichols...

Hi guys/gals. A bit of a problem has caused me to revisit PID/ PI controll= ers and tuning. I have this nice paper on the Ziegler=96Nichols tuning me= thod that compares the closed loop period to the open loop step response of= the system. It then shows the closed loop step response for different tun= ing parameters. But I can=92t seem to lay my hands on it... grumble. I=92= ll keep se...


New Video: Implementing the PID Controller in Software

Started by Tim Wescott in sci.electronics.design1 year ago
PID

https://www.youtube.com/watch?v=JVqJ7uRGwoA -- Tim Wescott Control systems, embedded software and circuit design I'm looking for work! ...

https://www.youtube.com/watch?v=JVqJ7uRGwoA -- Tim Wescott Control systems, embedded software and circuit design I'm looking for work! See my website if you're interested http://www.wescottdesign.com


PID Without a PhD, Finally

Started by Tim Wescott in sci.electronics.design2 years ago 128 replies
PID

Embedded Systems Design (or whatever they call themselves) kept moving this around -- so I've revamped it, updated it, and posted it on the...

Embedded Systems Design (or whatever they call themselves) kept moving this around -- so I've revamped it, updated it, and posted it on the web. Take a gander. Please comment on anything you like/don't like. I'm not sure if the way that I'm setting off the math is a Really Good Idea or a Really Bad Idea -- I'm trying to make it easy for the math-averse to skip over it, without breakin...


A question for you LM324 experts on failure problems.

Started by Jamie in sci.electronics.design6 years ago 17 replies
PID

We have some devices that have been in use for many years (not made by us). These are analog PID boards that employ a 324N chip. The...

We have some devices that have been in use for many years (not made by us). These are analog PID boards that employ a 324N chip. The circuit works very well and is very flexible in what it can do. THis is the problem. Lately been getting a few random failures of the op-amp. Today, one failed simply by turning one of the pots on the board that is in the feed back loop as the GAIN con...


I don't understand thermostats

Started by John Larkin in sci.electronics.design2 years ago 51 replies
PID

Imagine a mass that we want to heat with some closed-loop controller. It's C2 below. Voltage represents temperature. Thermal systems...

Imagine a mass that we want to heat with some closed-loop controller. It's C2 below. Voltage represents temperature. Thermal systems are diffusive, which we represent as a bunch of RC lags. Assume the voltage at C4 is the temperature sensor. If I were to design a PID controller, I'd have to really think about it, or fiddle some, to keep it stable. But if I do a dumb on/off thermostat, ...


small (3A) AC current measurement

Started by Luis Perez in sci.electronics.design6 years ago 22 replies

Hi guys, I'm trying to measure resistance, current, and voltage of a resistor (heater) connected to a 0-24V @ 3A transformer. The heater's...

Hi guys, I'm trying to measure resistance, current, and voltage of a resistor (heater) connected to a 0-24V @ 3A transformer. The heater's consumption is actually 2A max., and I'd be controlling it with a triac driven with an 8-bit micro, which I'd also use to get the above readings and send them to the host. This is my initial layout: https://docs.google.com/viewer?a=v&pid=explorer...


Improved Diode Recovery Model

Started by Tim Williams in sci.electronics.design2 months ago 7 replies

https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxyc3RldmVzY290dHxneDo1NjQ1Z TI1ZTY2MWFiM2Yz This had been discussed some...

https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxyc3RldmVzY290dHxneDo1NjQ1Z TI1ZTY2MWFiM2Yz This had been discussed some time ago. There was a lot of bragging about being able to create a model, but nothing came of it. Fortunately, this guy had beaten us to the punch, and released this paper publically. The design with multiple time constants makes me think of appro


State variable notch filter.

Started by George Herold in sci.electronics.design1 year ago 10 replies

I was trying to turn a previous SV filter into a notch, (Freq ~3.3 kHz, Q~10-20, see my mech. PID thread.) I was thinking of just subtracting...

I was trying to turn a previous SV filter into a notch, (Freq ~3.3 kHz, Q~10-20, see my mech. PID thread.) I was thinking of just subtracting the BP from the input. But almost all the web stuff I could find said add the HP and LP. (That seemed crazy to me, at high Q both those are peaking.. but then again the SV filter seems a bit crazy to me... two integraters in a row, come on. :^) S...


Tuning PDF loop (pseudo derivative feedback)

Started by Anonymous in sci.electronics.design4 years ago 42 replies
PID

I know about the auto-tuning algorithm for PID: cycle the temperature up an= d down, measure the peaks and distance between the peaks, and...

I know about the auto-tuning algorithm for PID: cycle the temperature up an= d down, measure the peaks and distance between the peaks, and calculate Kp,= Ki, and Kd. =20 But recently I've been experimenting with what Phelan called PDF, and am in= trigued by it. There isn't a lot of information out there about it, but ne= arly everyone that's used it has good things to say. =20 The prob...


Tom Frederiksen, RIP

Started by Jim Thompson in sci.electronics.design6 months ago 36 replies
PID

I just found out... Tom Frederiksen, RIP... Tom and I shared a cubicle at Motorola Semiconductor Products Division during the early to...

I just found out... Tom Frederiksen, RIP... Tom and I shared a cubicle at Motorola Semiconductor Products Division during the early to mid-60's. ...Jim Thompson -- | James E.Thompson | mens | | Analog Innovations


Mechanical resonances in PID l(oops)

Started by George Herold in sci.electronics.design1 year ago 19 replies

The oops is for stepping on Al's PI thread. Here (again) is the response, of my piezo/ aluminum flexure mount/ grating. (I'll post a pic,...

The oops is for stepping on Al's PI thread. Here (again) is the response, of my piezo/ aluminum flexure mount/ grating. (I'll post a pic, Thursday) https://www.dropbox.com/s/zftwx11a36zkypp/PIEZO-RESP.BMP?dl=0 The peak may be a little higher than shown, I cut the input by a factor of 2 for the highest peaks.. and the peak was clipping again. (If I drive the piezo too far the l...


Meaning of Vce(sat)?

Started by Daniel Pitts in sci.electronics.design4 years ago 29 replies
PID

I'm going to be using ULN2803APG in a design of mine, and I just noticed on the datasheet [1] that Vce(sat) typ is 1.3 at 350ma. Does that...

I'm going to be using ULN2803APG in a design of mine, and I just noticed on the datasheet [1] that Vce(sat) typ is 1.3 at 350ma. Does that mean that the voltage drop across the Vce will typically be 1.3 at that current? Or does that mean the voltage for Vbe needs to be that high to have saturation? [1]


measuring nanoamps with lots of noise

Started by Anonymous in sci.electronics.design2 years ago 30 replies

I am having a difficult problem on a current project so I was wondering if anyone could help. This is a project where I have to measure current...

I am having a difficult problem on a current project so I was wondering if anyone could help. This is a project where I have to measure current generated by a sample at high temperature inside a furnace. The current is in the picoamp-nanoamp range depending on temperature and I have been using a Keithley picoammeter. The furnace is controlled by a PID temp controller connected to


DIGITALY CONTROLLED RADIO RECEIVER

Started by RealInfo in sci.electronics.design5 years ago 5 replies

Hi all My question is about the structure of a digitally controlled radio like this http://www.hamradio.com/detail.cfm?pid=H0-010818 From...

Hi all My question is about the structure of a digitally controlled radio like this http://www.hamradio.com/detail.cfm?pid=H0-010818 From the point of view of the micro controller that controls it . If I understand well that micro does 3 main things 1> controls the frequency of the PLL that functions as a local oscillator used by the rf mixer 2> sends the relevant data to the