TS Controller...STOP~~~! READ THIS FIRST

[Oldman]

Ok bad news all. I got with Tech support at Dwyer Controls and Gages. They told me that the TS will not hold up under the load that a smoker would put it through. That we would burn out the points in a short period of time.

They are allowing me to return the controller. They strongly suggest a PID controller and solid state relay.

At the moment I'm so wrapped up in Raytheon on this complexed bid (was there again today with the facility manager for several hours) that I am just going to have to put this on the back burner.

Hopefully another member here who has a PID controller will take the time to do a STEP by  STEP outline of their success. Due note that one of my biggest frustrations when I set up the recipe site was the author wrote the recipe as if the reader had some knowledge of what they are talking about. You got a PID controller working then post it clear, clean and in a language that the rest of us can understand. This should include clear drawings... if you don't have a place to upload the drawing then send them to me. [email protected].

Thanks

Olds

[rgardjr]

What about using an SSR in conjunction with the TS?  That way the load wouldn't be on the TS.  This is how Norbert suggested hooking it up originally.  I think the PID & SSR combo is a little better option since the PID and TS are about the same price.  How long has Norbert had his up and running?

[Oldman]

Good questions....it will take a smarter person than me to answer them.

Olds

[bubbagump]

Olds,

It appears you got some incorrect information. I also contacted Dywer tech. support because what you were told did not make sense to me. I spoke with two different techs who confirmed the same thing.

First, The TS switch is strictly On-Off control. This means that its contacts simply open and close according to the dead band programmed around the setpoint. In other words, if you have a 200 deg. setpoint with a 2 deg. deadband, the switch will close its contacts at 199 deg. and open them again at 201 degrees. In reality, you will not be able to hold the temp. that close to setpoint because once the heating element is cycled off the remaining, residual heat, from the element will carry it beyond setpoint. And the same is true for the reverse. Once the thermostat reaches the lower end of the dead band it will turn the element on, but the temp. will continue to drop a bit because the heating element will take time to warm back up. If you remember Norbert mentioned that his temp. continued to rise 10 degrees beyond setpoint after the element was cycled off.

This type of control (On-Off) does not have the ability to control its output as the temp. gets closer to setpoint. It is essentially a dumb device. It only switches when the temp. reaches either the upper or lower end of the programmed deadband. While a smaller dead band will result more cycling of the contacts, a 4 amp. load on 16 amp. rated contacts will not destroy them in a short period of time.
In fact, Norbert also mentioned his on/off cycle was 7 minutes. That is a far cry from what a PID will cycle a SSR at when closing in on, and maintaining setpoint.

On the other hand, a PID is an entirely different control. Its like comparing apple and oranges. Unlike the TS switch a PID controller is a smart device that will monitor temperature and compare it to setpoint then adjust the output to <u>maintain</u> setpoint and eliminate the wide swings that on/off control will have.

For example, when my smoker is at setpoint my PID will fire my SSR repeatedly for tenths of a second to maintain setpoint. This rapid switching is what will destroy mechanical contacts. And again, this type of rapid switching will not occur with the TS temp. controller.

As far as using an SSR with the TS, you can, but it's not necessary and will not improve the accuracy of the controller.

So bottom line, the TS swich will work, it just won't control the temperature any where near as accurately as a PID controller.



Bubbagump

[nsxbill]

As one who is beyond challenged elecrically, I sure am happy with my BBQ-Guru Procom4/Raptor combination.  It works well, was a little pricey, but has remote features that make it shine.  

Bill

<i>There is room on earth for all God's creatures....on my plate next to the mashed potatoes.</i>

[mrdennisg]

After building mine in my spare time I had a lot of thought on this.

You can controll any amount of power you want with the smallest relay you just have to use something that will handel the amps called for . As an example my plan called for a relay to transfer power at 30 amp.
Look at the original plans and it shows my relay at 10 amp. Since most relays are maxed out at 10-12 amps. I thought I was stuck.

Not quite just use your relay as normal but put a contactor in the mix

Look at my prints and follow how the <font color="red">solid state contactor</font id="red"> wire is hooked up . It is on one leg of the heating circut triped by a
<font color="red">solid state relay</font id="red">

My Story:
How my Smoker Talks .

Power from PID says: "
ok let's turn on the heat
and smoke the meat"

Heat says: "I need 30 amps worth please"

PID says: "I can only handel a small amount because I am so state of the art......"

Contactor says: "Let me help I can get the power from PID to Heater with no problem "

Next week chapter two.

Using a PID on any exsisting heat circut is doable after all it's just a  (state of the art) thermostat right...
The only diference in using a PID is it is more state of the art and much more controllable.

[mrdennisg]

Iether I need glasses or a small picture sorry about that these are HUUUUGE[:I]

[nsxbill]

Mrdennisg

Right click on the picture and download the picture.  After that, open with graphic software.  I use Picture Viewer or Photoshop on my Mac.  Pretty much anything that will open a .jpg file will do.

Bill

<i>There is room on earth for all God's creatures....on my plate next to the mashed potatoes.</i>