# PID TO HEATING ELEMENT



## Slow42 (Oct 22, 2019)

The project is to connect a controller to a heating element, 120 volts, Max. 1500 watts. Daveomak suggests a very simple controller, Silicone controlled Rectifier. Very cheap and looks very simple to install just 4 wires. 

Can a digital PID be used to do what I’m attempting? I see many diagrams he on PID wiring but I’m not sure if it’s the same as what I’m trying to do. It appears the Silicone controlled Rectifier is always on where as the PID is not. Will the PID allow the heating element get to maximum temperature of the element I’m using, 1200 watts? I realize this way is more complicated and expensive but I’d like it as a option. 

Right now I have the element and have ordered some high temperature wire as I will be placing the heating element at different locations within the smoker to see what effects it will have on the overall heating. The element will not be going through the back wall where the original element was attached.


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## dernektambura (Oct 22, 2019)

could you post PID and SCR pics or models?


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## Slow42 (Oct 22, 2019)

This is the controller Daveomak suggested and is very simple to install and operate and is very cheap, Amazon. I haven't purchased anything yet. There appears to be many PID controllers cheap to very expensive.






*Motor Speed Controller, DROK Motor Control Board AC 110V 4000W Adjustable Voltage Regulator SCR High Power Dimmer Controller Temperature Governor Dimming Monitor $13.99*


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## dernektambura (Oct 22, 2019)

I would suggest to go with SSR.... SSR and SCR Both of them essentially have a same function to regulate heat element operation..... PID will control any type of TC ... SCR regulate voltage at output....In your case, 120 VAC and 1200WATTS = 10 AMPS...


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## JC in GB (Oct 22, 2019)

You can get a PID controller and SSR for less than $20.

I put one together for Sarina my Stump's Baby...


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## cmayna (Oct 22, 2019)

I use a Auber PID controller # WS1500EMP, which is not cheap but is so freakin' simple to hook up and operate.  The MES's element is connected directly to a power cord which plugs into the back of the controller.


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## Slow42 (Oct 23, 2019)

Thanks the Auber is very nice but! I went with both a PID and a rectifier. If one fails or one is to complicated I’ll have a backup. I also have an inkbird controller for my fish tank heater. Max range is 210 degrees F, and 10 amps. This might work also at Lower temperatures.


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## Slow42 (Oct 26, 2019)

I’m using this PID to start. I wired the heating element so it can be removed from the smoker. Tested everything and it works great. Not an ideal setup but could be adapted to pretty much any size box pending the size of the heating element. Now to see if it heats my smoker up to temperature as the heating element is a bit small, toaster oven. 
The wire is high temperature, 500c or 932f, 16 feet, $8.00, from Amazon.


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## Slow42 (Oct 27, 2019)

I spoke to soon on the element working properly. The element keeps tripping the GFI. I removed the ground and everything works fine. I had attached a ground wire from the element to the green wire on the power cord. This doesn’t seem to work as it trips the GFI. I tried attaching the ground wire from the element to the smoker box and that worked. I’m trying to be safe here so what am I doing wrong? Any suggestions?


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## sigmo (Nov 3, 2019)

if the heating element, removed from the smoker, with the ground wire of the power cord connected to the case of the element trips the GFCI, it indicates that there is leakage current flowing from the actual heating wire (NiCr) element within the heating element's casing to the grounded casing of the element.  That is not acceptable, and this leakage is what's tripping the GFCI.

Where did you get the heating element?  Is it new?  You won't want to use a heating element that has leakage from the actual heating element to its casing.  You should be able to ground the element's case and not have a GFCI trip.

If the cabinet of the smoker is properly grounded, and the element is mounted so that it's casing is electrically grounded to the grounded case of the smoker (as it should be), then this should also be tripping the GFCI.  And, again, that indicates a problem in the heating element, and you probably need a new element that doesn't exhibit this sort of failure.

Keep in mind that all of this sort of wiring and design needs to be done right.  It always scares me to some degree when people engage in these "Do It Yourself" projects when it involves electricity.  Many of the folks on here doing these types of projects have a lot of experience and background in electronics and electrical design, construction, and the like.  So they make it look easy.

And sometimes people do these projects, and they're not done safely, but luck has kept them from having serious problems.  So one sees encouraging posts about "builds" that may be unsafe.  And all of this encourages people to give it a try.

And of course, I love the spirit of experimentation and homebrewing that forums like this inspire and the help and growth of the whole hobby is fantastic.  The transfer of ideas and information here is wonderful.  So I don't want to dampen any of the enthusiasm or discourage people at all.

But getting something wrong when it comes to electricity and fire, etc., can truly be a matter of life and death.  So be extremely careful and positive that everything is done safely and properly.  If you do need help, don't be afraid to ask someone you know who has experience with all of this.

People on a forum like this can offer a lot of help.  But we can't be there with you to make sure everything is really safe.  And just because something works doesn't mean it's safe.  Just be careful.

There's a lot to all of this.


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## JC in GB (Nov 3, 2019)

If I read your post correctly, you attached the green ground wire to one of the terminals on the heating element?

That will trip the GFCI every time.

The ground wire should be attached to the metal chassis with the hot and neutral insulated from the chassis.

Like sigmo said above.  Stay safe.  If you are not sure about power wiring, ask someone who is to help you.  An improper wiring job can be very dangerous.

JC


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## Slow42 (Nov 3, 2019)

First thank you for the safety warning I do my best at that.
I tested the element out of the case on table top. White wire to one terminal black to the other of element. The ground was connected to the hole in the element bracket. This is from the power cord directly. The plug was not GIF.  It worked.

Transferred the element into the smoke just as described above. Plug was a GFI. The GFI tripped. As JC in BC and Daveomak stated this is incorrect and would trip GFI, which it did. I removed the ground wire and attached to smoker box and everything worked properly and has so continuously.

So both elements have a hole where there was a wire attached; just the wire as they are both used. Those wires I assume went somewhere, ground to the smoker box? Still don’t know. But it now works.

I did put this in another post also as not to confuse he PID issue.

thanks for the help


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## sigmo (Nov 4, 2019)

Connecting the ground wire to the bracket for the heating element should NOT cause a GFCI to trip.

The fact that it did shows that the element is bad.

The fact that it didn't with the element mounted in the smoker shows that there is some fault in the wiring of the grounding system in the smoker.

That element bracket should be grounded to the chassis of the smoker.  And the chassis of the smoker should be grounded to the ground connection of its power cable.

Something is wrong.

If I'm reading your posts correctly, you didn't connect the ground to either of the power terminals of the element.  You connected it to element's mounting bracket.  That is correct, and a good test.  For that arrangement to trip the GFCI shows that there is leakage current flowing from the actual heating element to the element's outer shell and mounting bracket.  That's NOT GOOD.

And worse, it's NOT tripping the GFCI with it all mounted in the smoker.  And that means that something is NOT connected correctly in the smoker.  So this sounds very dangerous.  If there is leakage current flowing from the heating element out through its insulation to its case, and that is not tripping the GFCI with the element mounted in your smoker shows that the element's case is not grounded now.  If it was, the GFCI would trip in both situations.

This needs to be explained and fixed.

Again, is this a new heating element?  It should NOT trip a GFCI with its bracket tied to the power cord ground wire.


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## JC in GB (Nov 5, 2019)

Just a note.  Resistive heating elements can trip GFCI outlets and have nothing wrong with them.   The ground to the smoker chassis should be sufficient as long as you are not tripping circuit breakers. 

Why would you want to run your smoker on a GFCI outlet any way?  A standard three prong grounded outlet should be all you need for that.


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## Slow42 (Nov 5, 2019)

The GFI trips when the green ground wire, from the power cable, is attached to the heating elements mounting plate, not the, I’ll call, element electrode.  Several members say this is not correct. It does not trip the GFI if I attach the ground to the smoker box.  Both elements are used.  I haven’t connected the heating element to the smoker box as of yet. I will try this but for now everything works with the ground wire, from the power cable, attached to the smoker box.

I use a GFI for the smoker because that’s what installed on my deck. don’t have any other options. 
So what I’m going to do next is attach a ground wire from the heating element to the smoker box then attach the ground wire, from the power cable, to the smoker box.


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## sigmo (Nov 5, 2019)

JC in GB said:


> Just a note.  Resistive heating elements can trip GFCI outlets and have nothing wrong with them.   The ground to the smoker chassis should be sufficient as long as you are not tripping circuit breakers.
> 
> Why would you want to run your smoker on a GFCI outlet any way?  A standard three prong grounded outlet should be all you need for that.



Current NEC requires all outdoor outlets as well as all outlets in garages to be GFCI protected.  Thus, anyone with a deck or garage that is wired to meet current code will likely be plugging their smoker into a GFCI protected outlet.  And most folks won't want to rewire an outlet to eliminate the GFCI.

There should be no reason for a good resistive heating element to trip a GFCI outlet.  In fact, resistive loads are the least likely loads to create nuisance trips of GFCIs (unlike motor or other inductive loads, which can create arcing at switch contacts as their magnetic fields collapse when the switch interrupts the current during parts of the cycle other than zero-crossing of the current (not voltage) waveform).

If a resistive heating element trips a GFCI, that means that there is leakage current above the threshold for that GFCI flowing.  And there's no reason for that to happen unless the insulation in the element (the mineral packing between the actual heating element at the outer sheath) is compromised OR there is a buildup of gunk or moisture at the uninsulated area where the heating element is exposed just where it enters into the mineral insulation in the ends of the sheath tube of the element.

The reason code requires GFCI outlets for outdoor or garage outlets is because of the high likelihood that tools or appliances will be used and touched by people whose feet may be in contact with soil, damp concrete, or other grounded surfaces, thus providing a potentially deadly path for current to flow from  the tool or appliance through the person on its way to ground.  That path through the person can end up being particularly lethal because it can be through the heart where even relatively small currents can disrupt the heart rhythm by interfering with the very tiny electrical impulses that ordinarily control the heart muscles.

This is the same logic that code observes when requiring GFCIs for any wet location or kitchens, bathrooms, etc., these days.  The potential for the victim to be in contact with a ground makes it important to protect against "ground faults" (current taking a path to ground other than through the neutral conductor).

Of course, if the appliance is properly grounded, then the leakage in (or at the terminal area of) the heating element _should_ find its path to ground through the grounding conductor of the appliance cord, and the case of the appliance would then not be driven to a dangerous voltage.  Thus, you would never be in danger, nor would you even realize that this leakage was taking place.

The code requirement for the GFCI outlets in these areas protects potential victims even if the appliance becomes ungrounded for whatever reason AND it alerts the user to an internal fault in the appliance even if the unit _is_ grounded.

And this is what disturbs me about the OP's situation.  Clearly, his heating element has a short inside of it.  (Perhaps a high-resistance short, but a short, nonetheless) between the element and the sheath (and mounting bracket) of the element.  His test where the element trips the GFCI when the mounting plate is grounded proves this.  So we know his heating element is defective.

Yet with the element mounted in his supposedly grounded smoker, the GFCI doesn't trip.  That means that either the mounting bracket of the heating element is NOT tied to the chassis of his smoker OR his smoker is not grounded.  Both of those are potentially deadly situations.  So he needs to figure out what's going on.

Older GFCIs were more prone to nuisance tripping than newer ones.  I do understand how GFCIs can be a pain, especially for appliances with motors that may create transients as their motors are switched-off mid cycle, though.  I even have a freezer in my garage that specifically says on one of its labels to NOT connect it to a GFCI protected outlet.  Presumably it is known to generate transients when its compressor switches off, and they don't want you to end up with a freezer full of spoiled food when it trips your GFCI.

Technically, there's no legal and safe way for me to use that freezer in my garage.

So I wired an outlet just for it that is NOT GFCI-protected, and which is behind the freezer, so nobody can plug in a tool or extension cord to that particular non-protected outlet.  However, this would not pass an electrical inspection these days.

Newer fridges and freezers as well as other appliances are designed to not generate transients that trip GFCIs.  And newer GFCIs are designed to not trip from motor transients.

But I understand your point!

Still, I'd want to know if there was leakage current from hot to ground in any smoker or other similar gadget of mine.  And if it did trip the GFCI, I'd want to find the location where the leakage was happening and fix the problem before it got bad enough to cause a more serious issue, even if the appliance was safely grounded.

This is one of those things where you can see both sides of the argument!  :)

But what has me really concerned for the OP is the fact that his GFCI test of the element alone proved that it's defective and leaking.  Yet his smoker with that element installed is NOT tripping the GFCI.  Either the smoker isn't really grounded OR the element is not grounded to the smoker's case.  Both are potentially lethal situations.

And keep in mind that this is a DIY build that we can't test and troubleshoot for him,.


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## sigmo (Nov 5, 2019)

Slow42 said:


> The GFI trips when the green ground wire, from the power cable, is attached to the heating elements mounting plate, not the, I’ll call, element electrode.  Several members say this is not correct. It does not trip the GFI if I attach the ground to the smoker box.  Both elements are used.  I haven’t connected the heating element to the smoker box as of yet. I will try this but for now everything works with the ground wire, from the power cable, attached to the smoker box.
> 
> I use a GFI for the smoker because that’s what installed on my deck. don’t have any other options.
> So what I’m going to do next is attach a ground wire from the heating element to the smoker box then attach the ground wire, from the power cable, to the smoker box.



This tells me that the reason your GFCI is not tripping is because you don't have the defective heating element grounded to the case of your smoker.  So having the smoker grounded doesn't complete the path from the leaking heating element to ground.

This is dangerous because the case or "outer tube" of your heating element is probably electrically "hot".  If, for example, a foil cooking pan comes into contact with the element, and you reach in and touch it while also touching the grounded case of your smoker, YOU will become the path for that leakage current, and may be killed.  The element needs to be grounded to the case of the smoker.

And if that trips your GFCI, then that simply reinforces the fact that you need a non-defective heating element to replace the one you're currently using.  Heating elements are dirt cheap.  Many on-line appliance repair parts places sell a variety of them.  Don't leave things as they are.

As I said before:  Just because something works doesn't mean it's safe.  :)

You got some great troubleshooting information by trying the element by itself with its mounting bracket grounded and seeing that trip your GFCI.   Don't ignore that valuable test result.


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## Slow42 (Nov 6, 2019)

I just wanted to smoke some bacon not myself so this project in the trash can for now.  
Everyone one has been so very helpful. You all are very knowledgeable but have different opinions about the grounding situation.  I surly won’t be able to figure it so. Thanks again for the help.


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## dr k (Nov 6, 2019)

If the element is disconnected and out of the smoker and one probe of the ohm meter at its highest setting is on a male spade, there should be no continuity to the element jacket or bracket.


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## Slow42 (Nov 6, 2019)

Dr K I went to an appliance repair business and they tested both my elements. They tell me that there is nothing wrong with either element in the way you suggested to test. Not to say there isn’t anything wrong with the element but only that it tested ok with this test. The problem lies in the way the ground is to be connected I guess.  I just want to make just the bacon gets smoked not me.


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## JC in GB (Nov 7, 2019)

The refractory material in the heating element can absorb moisture over time in different circumstances.  This will put it in a low mega-ohm state (5 Mohms or less) that can and will cause nuisance GFCI breaker trips.   You can test this by running the heating element for a period of time and measuring the insulation value  again.   It should now be 20 Mohms or higher.  This should get rid of the nuisance GFCI trips.  If after this test, you still have GFCI trips, plug unit into another GFCI outlet and if that trips, I would conclude that the insulation of your heating element has degraded to an unsafe point and should be replaced.  If it does not trip, I would say you have a stressed GFCI outlet and should replace it.


JC


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## Slow42 (Nov 7, 2019)

The repair shop did test the ohms and he said it was 30. At least from your explanation I know what he was talking about. And I can replace the GFI but it works for everything else I use it with.  Its my only one. I have no problem buying a new element but don’t want to waste money if the same problem occurs.  Thank much for sticking through this and helping me.


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## JC in GB (Nov 7, 2019)

Sounds like he measured the resistance of the heating element itself.  Did he measure from the element to the case?


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## Slow42 (Nov 7, 2019)

No I took the elements to his shop.


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## JC in GB (Nov 7, 2019)

Slow42 said:


> No I took the elements to his shop.



I meant from one of the power terminals to the outside of the heater element.

The element itself will be low ohms.

The element to ground should be in the mega ohm range....

As others have posted, safety first.  I think you can answer your question about the usefulness of that element with the two performance tests I outlined.

Wishing you success!


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## sigmo (Nov 7, 2019)

I'll bet they didn't check for leakage with a "megger" (high voltage megohmmeter). They probably just ohmed the elements to see if they were "open".

What I'm concerned about is that your GFCI tripped when you had the mounting bracket tied to ground.

Unless you had something connected wrong when you did that test, the GFCI saw leakage current within the element.

When you later tried that same element mounted in the smoker, did you have its mounting bracket electrically connected to the frame of the smoker?

If so, was the smoker grounded, too?

Because if the heating element's bracket was electrically connected to the smoker chassis, and the smoker chassis was connected to ground, then the same thing should have happened (the GFCI should have tripped).

So my concern is that the GFCI didn't trip, but it should have. So I think something wasn't properly connected when you had the element in the smoker.

I hope that makes sense.

Edit To Add:

I need to stop reading and especially posting to this forum from my phone.  I did not see a number of posts that took place above this post before making this post.

It looks like 

 JC in GB
 already covered a lot of this very well.

I agree that if the mineral insulation in the heating element absorbs moisture, that could create a leakage situation.  And because heating the element may well drive enough moisture out of the element's insulation to lower or eliminate that leakage, I can imagine a scenario where the first test-heating of the element drove out enough moisture that when it was later installed in the smoker, it was dry enough to be safe, and no longer trip the GFCI.

I'd still make sure that the element's bracket is grounded to the smoker, and the smoker is grounded properly.  But if, with things properly assembled, the element doesn't trip your GFCI, then everything may be just fine.

If it was me, I'd reassemble things and then measure the resistance from the sheath of the heating element to the ground pin of the smoker's ground pin.  That resistance should be very low.  Ideally, below one ohm.

If you've got good continuity from the heating element sheath through to the ground pin of the smoker's power cord, then you should be good to go.  And if the system doesn't trip your GFCI, then that's excellent!


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## TorrinFu (May 4, 2020)

Hi...most of them use infrared spot lights or heat lamps? Using resistance wire your heating places that don't need the heat. My youngest son worked for a while at a company that did both roto molding and vacuum molding. They used infrared heating elements, like a Calrod. Toaster ovens from second hand stores are a good source for them.


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