Found a new use for a PID

[10x]

Talking to my local pharmacist - a young lady who I have known all her life.
The discussion came to making candy and the need for temperature control.
I mentioned the PID - now she wants one.

[Walter Laich]

I put one on my Lyman 4500 back before PC

just wire-tied it to the side of the reservoir

cheap one off of ebay--is in C° but not a problem to figure out what number is correct for melting lube

[bangerjim]

I design and sell industrial grade (high $$$$$$) PID-based control systems. You can control anything (pressure/temperature/flow/level) with a PID controller......applied correctly.

The newer generation of REALLY cheap (Chicom) controllers puts them in range of the average person!

Banger

[jjamna]

What amperage do the PID's you guy's use handle? I have considered one to regulate my electric smoker. It is an old one that has one temp and it is 240 to 260 depending on the weather. I tried a variable speed motor controller on it and it melted (rated at 15 amps). Melted where the element plugged in to it.

[10x]

What amperage do the PID's you guy's use handle? I have considered one to regulate my electric smoker. It is an old one that has one temp and it is 240 to 260 depending on the weather. I tried a variable speed motor controller on it and it melted (rated at 15 amps). Melted where the element plugged in to it.

Using a solid state relay the amperage of the PID is not relevant. The amperage of the relay is. I believe the SSR (Solid state relay) can handle 40 amps. They run about $3.50 shipped from china.
The PID controlls the solid state relay. The relay does need to be on a heat sink if the amperage is high
https://www.aliexpress.com/item/FREE...StoreLevelAB=1

[jmorris]

I have been using them for years on my smokers.

[jjamna]

I have been using them for years on my smokers.

Will the one's they are selling here work? I know nothing about them.

[bangerjim]

Controllers are the "BRAINS" of the system that controls the "final element". That can be anything from a valve to a thermal element to a pump to a positioner...AND......including a solid state relay.

Most controllers are used with the 4-20 madc proportional (varible) output to drive variable final elements, not just simple on-off heaters and SSR's.

PID (proportional/integral/derivative) style controller have been around for many decades. I started out using them back when they were pneumatic! People on this forum have just discovered what they can REALLY do just in the past couple of years.

[Catshooter]

I use one for lard rendering. Controls an electric roaster perfectly.


Cat

[bstone5]

Use a PID to control temperature in a parkising tank. A stainless steel water heater heating element is used to heat to 180 degrees, works very good in maintaining a constant temperature.

[Dragonheart]

I installed a PID on a 30" wall oven I converted for powder coating. The all digital oven had a bad control panel, which would cost $$ to replace, so I got it for free. Cost me about $60 in parts to set up the PID to control the two 220V elements. Set the PID up with a relay, heatsink and fan you should have no problems as my relay operates under 90 degrees.

[ChuckO]

Aside from using a PID on my casting pot and my convection oven for PC applications I have two in use on my home built brewery and one on a sous vide water oven in the kitchen. I've found that everything works best if the electronics are kept separate from any heating appliance, heat is the enemy of electronic devices.

Most of us don't know it, but we are using a form of a PID when we use cruise control in a car.

[bbogue1]

My PID is in a kids metal lunch box. The box holds 2. When I use them both I use one for the lead pot and the other for a hot plate for molds. It does not matter what the electrical device is that the PID is controlling (the load), the PID turns on the electricity when needed and turns it off when a set value (temp) is reached. You can choose to use them separately, I can use either one to control my PC oven and either one to control my smelting hot plate, just leave the unused one turned off. Both are RexC100 Chinese and are not as adjustable as some, but, they certainly do the job and the entire set cost under $50 for both PID, both SSR all the wiring and the lunchbox. Attachment 209038 and here is my actual schematic Attachment 209039 I am building one for a shooter in Alabama and I'm putting it in a Double Bubble lunch box. It does read in C but that is no problem since I only use 4 temps and I wrote them on the top so I don't have to look them up. Heat in the box has never been an issue. It sure has reduced my rejects when casting and since I can assuredly set the smelting temp below 750 and maintain the temp I have no worries about zinc.

[jmorris]

I used one in my egg incubator too.



Wound up using a cold air humidifier controlled by another device vs the sponge and water.

[LenH]

I have been using a digital controller for an old electric smoker. The heating element is rated for 1000 watts and the unit will keep the temp where I set it.
I keep probes for different things. The smoker, the lead pot & for the toaster oven when I powder coat.

[jmorris]

But I have been using them for casting since before they became popular.



They actually used to be quite expensive.

[Dragonheart]

Yes, electronics are terrific, wonderful problem solvers and work savers ................. until they flood! Just ask the tens of thousands of car owners in Houston whose vehicles went underwater.

[bangerjim]

For years past, I have sold industrial grade controllers for anywhere beteen $600 and $1200 - depending on the control loop sophistication needed. These are NOT the teeny postage stamp size people on here use. Industry prefers the DIN and 1/2DIN sizes that can easily be seen across a control room.

With the flood of cheap ChiCom products, those teeny controllers are now easily within the price range of most who want to mess around with them - and using one dedicated to each application, rather than swapping one around to several applications, is very doable for anyone today. And the lower quality ChiCom bare metal rod t/c's (actually made to mount in a thermowell for protection) have flooded the market. Add to that the usage of cheap ChiCom SSR's makes building an on-off control loop pretty inexpensive, compaired to previous times.

My shop is currently working on a control system that uses large format three mode controllers with feed-forward capabilities, computer LAN interface, and 4-20 madc control output feeding 800amp industrial solid state variable output 3 phase 480V modules. Now THAT is PID+ control! And how industrial heat treat vacuum ovens are controlled. All done with made in USA and Europe products. (Yes.....I know components are sources worldwide, so don't bother going there ) Buy USA!


Isn't technology amazing.

[jmorris]

Yes, electronics are terrific, wonderful problem solvers and work savers ................. until they flood! Just ask the tens of thousands of car owners in Houston whose vehicles went underwater.

Pretty hard to avoid electronics these days, anything a PID would control would also be electronic.

A lot easier to avoid floods than electronics.

However, I agree. Your 2018 automobile would likely be toast in a flood where your 1947 Ford 8n would just need a change of fluids.

[bangerjim]

Pretty hard to avoid electronics these days, anything a PID would control would also be electronic.

Not necessarily. I control not only heaters via triac/SCR packs but pump and conveyor motors, industrial mixers, combustion dampers, pneumatic valves via I/P (electro/pneumatic) positioners and all kind of stuff that is not directly purely "electronic". Even lighting systems of specific types.

Your imagination is the only limit to the possibility of PID controllers and thier uses.