# MES Mod Madness Teaser Pics!!!



## tallbm (Apr 26, 2017)

Well for about a month or more now I have been alluding to doing all kinds of mods like a MES40 Gen1 rewire for PID, the HeaterMeter PID controller, a convection fan, and a custom built controller box to house everything including a variable speed fan control.

Well he excitement has gotten to me.  It is not completely finished and not 100% tested but I would say barring any catastrophes I'm about 85% of the way there.  Everything works individually, everything is functions when assembled, but some kinks and finishing touches are being worked out but everything looks promising!

So here are some tease pics, enjoy!

*HeaterMeter PID Controller Pic(s):*

If you don't know about this guy it's a digital controller with wifi capability.  It is built of the Raspberry Pi 3 technology/pc board













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__ tallbm
__ Apr 26, 2017






*MES40 Gen1 Rewire WITHOUT taking off the back! :*  

(Testing unplugged wires for continuity with a $10 Multimeter to determine which was Hot and which was Neutral.  The MES wires to the heating element both have black insulation so no color identification possible with wires.  No need to tear off the back and follow wires using this method 
	

	
	
		
		



		
			






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__ tallbm
__ Apr 26, 2017






[Edit: Updated text and image to correctly reflect wiring connection described for the image. ]

Hot Power plug to Hot MES wire that goes to heating element.  I got cute and used a male spade connector to leverage the existing female spade and I then leveraged the existing insulation covers that came with the MES.













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__ tallbm
__ May 6, 2017






Both Neutral and Hot power chord wire to Neutral and Hot MES Wire that goes to heating element.













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__ tallbm
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*Heating Element Rotation (Flip) to Center it Up:*

I got the idea to copy this mod from user @cmayna  and his mod post doing so, Thanks!

I figured this would help with the fan mod and generate heat from the center rather than 1 side.  I use a Mailbox Mod and AMNPS for smoke so no need for the all the other stuff.  You can also see the fan shaft there above the element.

I also flipped over the metal bars thingy under the heating element, this was to turn downward the metal flap that it contains so that it does not touch or interfere with the heating element.  Worked like a charm!













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__ tallbm
__ Apr 26, 2017






*Convection Fan Pic(s):*

Large back hole drilled, stainless steel sharpie body inserted and cut with a dremel cutting wheel to be the fan shaft tube to prevent smoke from getting into smoker insulation and body. Silicon seal will be applied to seal the gaps around the tube once all kinks are worked out.













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__ tallbm
__ Apr 26, 2017






Fan mounted to smoker body and plastic housing mounted smoker body around fan.  Fan shaft is poking through to the inside!













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__ tallbm
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All sealed up.













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__ tallbm
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Shaft on inside with sharpie tunnel (need to seal the extra hole space with hi temp Food safe silicon). Fan blade on. Rack, Waterpan, and Heating element Clearance all good.













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The money shot of the fan blade spinning!!!













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*Custom Controller Box:*

Plug, outlets, and power switch all labeled













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The guts.













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Probes outlet and heatsink to Solid State Relay (SSR)













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Variable speed fan controller.













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It's alive!!!!













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Closeup of HeaterMeter PID display.













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Well guys if you have made it this far I hope you enjoyed pic heavy the tease.  

I do plan to do some detailed posts about some or all of these mods so others who are interested and capable can benefit from them.  

I think the "no back removal" MES rewire tips will be super helpful and I will include the measurements for adding a back panel for the Rollout Limit Safety switch, which I did not show in the pics above.  I swapped mine with a 350F manually resetable switch and used high temp steel connectors.  

[EDIT: I believe a couple of other members on different posts pretty much confirmed that the MES stock Roll out limit switch is an auto-resetable one rather than a one time tip]

I don't like the idea of the one time use 302F switch being there without me being able to access it.  Plus the higher 350F threshold will give me some margin for error as I manually tune my HeaterMeter PID to get things heating properly. 

I hope you enjoyed and thanks for stopping by!


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## daveomak (Apr 26, 2017)

Nice mod.....   I'm interested in a part. no. of the fan and motor....  and where you got them....


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## tallbm (Apr 26, 2017)

DaveOmak said:


> Nice mod.....   I'm interested in a part. no. of the fan and motor....  and where you got them....


Dave the parts are:


Frigidaire 316136300 Range/Stove/Oven Fan Motor - purchased on Amazon for just under $25 prime shipping

318398302 OEM Frigidaire Fan Blade #12239 - purchased on ebay for $7.33 including the shipping

Stainless Steel* Left Hand* Hex Nuts 1/4-28 nuts - purchased on ebay  from vendor "stainlesstown" for $5.95 and free shipping.  Notice what is needed is a Left hand nut not a normal right hand!!!  This is not the correct nut/part but it works with a little rigging by using another larger nut as shim to fill the extra space between the end of the fan shaft threads and the fan blade.  There is a gap that this nut cannot close to touch the fan blade when the shaft's threads end.    I could not find the exact Frigidaire "part" for the nut but with some serious digging I managed to find out the size, thread count, and left hand orientation.  Again, the nut I ordered works with a little extra rigging.
I looked up these parts and they go together but it was hell finding that info and I didn't save it so you will just have to believe me or feel free to do a little Googling and I'm sure you will find that the parts match.

Oh by the way I used a little gorilla glue to glue some other large 1/4 nuts to again act as a shim for the fan motor's feet where the screws go.  The hole for the fan haft happens to fall close to the heating element panel.  Without the extra shim space the fan motor cooling fan blade touches the screw heads of the heating element panel :(  

Again a little rig job with glued nuts over the holes made enough of a gap so that the cooling fan blade on the motor would easily clear the screw heads on the panel.

Lots of little tricks and tips I had to create in order to get things to work out well.  Nothing crazy but definitely something that I will point out if/when I post about each mod in detail :)

I hope this info helps!


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## SmokinAl (Apr 27, 2017)

Very interesting!

I can't wait to see how it all works!

Al


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## johnnyb54 (Apr 27, 2017)

Very interesting! Just a quick question, while I see the benefit of flipping the heater element so it's more centered why the need for a fan? Is the fan constant RPM or does it ramp up and down automatically according to conditions in the smoker? Thanks.


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## tallbm (Apr 27, 2017)

johnnyb54 said:


> Very interesting! Just a quick question, while I see the benefit of flipping the heater element so it's more centered why the need for a fan? Is the fan constant RPM or does it ramp up and down automatically according to conditions in the smoker? Thanks.


The idea behind the convection fan is that it will constantly stir the air in the smoker to keep temps as even as possible throughout the entire smoker the same way a convection oven works.  I'm trying to eliminate hot and cold pockets of air.

The fan will run at a constant speed.  The fan will be connected to a variable speed controller, controlled with a dial.  The speed variations aren't that great, more like off, low, and high but I had nothing to go on so it was a total design decision guess for the variable speed and I had hoped for more speed variation.  But hey, I guess 2 speeds is better than 1.


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## johnmeyer (Apr 27, 2017)

That fan is going to be the wild card in this mod. I have no idea whether it will be really good thing, or a really bad thing. It will, for sure, be a thing: something will happen.

It would seem that some or all of the following things will be true:

1. More air circulation will dry out the food.

2. More air circulation will cook faster.

3. Air circulation may change how much smoke is deposited/absorbed by the food (I have no idea whether it will be more, or less).

4. Air circulation may change how much smoke is exhausted through the top, especially if you are using an external smoke generator (mailbox mod, etc.)

I will be really interested to hear what you think the fan pros and cons are after you've done a few smokes. I think it is a great idea to try, and I'm really glad you are doing it and are willing to share the results of your design.


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## daveomak (Apr 27, 2017)

nepas used a fan in one of his smokers for years.....


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## johnmeyer (Apr 27, 2017)

DaveOmak said:


> nepas used a fan in one of his smokers for years.....


And how did it change things?


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## daveomak (Apr 27, 2017)

you will have to PM him and ask ,,,,,, unless he sees this...  took me awhile to find it... BUT...   I remembered it...

And i installed a fan at the rear to control the high and low temp spots inside the cabinet. This also circulates the smoke from the AMZNPS.

http://www.smokingmeatforums.com/t/121262/dried-slim-jimmys













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__ daveomak
__ Apr 27, 2017


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## tallbm (Apr 28, 2017)

johnmeyer said:


> That fan is going to be the wild card in this mod. I have no idea whether it will be really good thing, or a really bad thing. It will, for sure, be a thing: something will happen.
> 
> It would seem that some or all of the following things will be true:
> 
> ...


Yep I will have to figure out what it does and doesn't do for me and HOPE it has more pros than cons.

I did a good amount of research online to be convinced it should be a good mod.  A majority of the information was from other people doing fan mods in electric smokers.  I did find it odd that this amazing forum did not have much info on fan mods, but maybe I can add a little info to help out the next guy :)

If things do not work out well then I always have the ability to flip a switch and turn off the fan.  I'm not backed into a corner with it so I should be ok no matter what.


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## tallbm (Apr 28, 2017)

UPDATE:

Hi Temp 600F FDA approved, food safe, Silicone Sealant added to any gaps and holes created in smoker during/for mods.  Just needed it to cure for the full 7 days before heat tests.
Fan mod kinks worked out and assembly test passed.  Assembly testing = things put together which includes the silicon seal.
HeaterMeter kinks worked out and assembly test passed.  
FYI, the HeaterMeter really NEEDS a 12v 3Amp power supply.  T

The documented and suggested 12V 1Amp power supply is the minimum for the electronics (Raspberry Pi 3) specs  
	

	
	
		
		



		
		
	


	





As more devices are added/managed and drawing power from the HeaterMeter (wifi, SSR, etc.) the more power needed.  The HeaterMeter device produces power consumption spikes as it engages hooked up devices which then causes a starvation of power situation that then causes the HeaterMeter device to reboot.

More available power means no power starvation during consumption spikes

Next UP, Testing:

Do a full Test of the device by executing a 3 hour "seasoning" with all devices assembled and running and adding smoke for the last hour and a half or so
Do a chicken smoke (chicken is cheap) with everything running including smoke.  I plan to double/triple up on the smoke since the overall time would be short and even shorter than normal if the fan is doing it's job.
Fix any kinks and perform the testing cycle again as needed.  
Thanks for hanging around for the ride guys! :)


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## sundown farms (Apr 28, 2017)

Really looking forward to your experience with the convection fan. That is something I could install. We really like the convection oven in the kitchen.  Did you consider mounting the fan above the chip tube so it would blow the heat toward to opposite side and away from the top vent?


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## johnmeyer (Apr 28, 2017)

Are you planning to still generate smoke within the smoker itself, using the original chip tray? If so, it just occurred to me that the fan man wreck havoc with that process. You know what happens when you blow on the embers of a campfire: they get really hot and flame up. Even if the fan isn't blowing directly across the chip tray, the extra circulation may have some of that same effect.

Of course maybe you said that you were using an external smoke source, and I missed that.


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## tallbm (Apr 29, 2017)

Sundown Farms said:


> Really looking forward to your experience with the convection fan. That is something I could install. We really like the convection oven in the kitchen.  Did you consider mounting the fan above the chip tube so it would blow the heat toward to opposite side and away from the top vent?


I did think about mounting the fan in that location or other locations.  I decided to go with the position over the heating element because all convection oven designs and info I found had the fan always mounted over the heating element at the back of the stove.  Additionally all of the fan mods I found online for electric smokers had it in the same spot, over the heating element in the back.  I went with the general information, designs, and approaches used by other fan mod examples that seemed to have success.

If you do the mod the way you mention I would love to see how it turns out! :)


johnmeyer said:


> Are you planning to still generate smoke within the smoker itself, using the original chip tray? If so, it just occurred to me that the fan man wreck havoc with that process. You know what happens when you blow on the embers of a campfire: they get really hot and flame up. Even if the fan isn't blowing directly across the chip tray, the extra circulation may have some of that same effect.
> 
> Of course maybe you said that you were using an external smoke source, and I missed that.


I use a mailbox mod so no smoke generation using the original chip tray.  From what I can tell from other people's fan mods for electric smokers I should be ok.  

Most of the fan mod examples I found were with bradley smokers which has the smoke generation outside of the smoker unit with the puck burning contraption attached to the side.


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## tallbm (May 6, 2017)

UPDATE:

Ok so yesterday I was excited test out my MES with all of the mods (Heatermeter, fan, flipped element, etc.).

I loaded up the smoker with simulated heavy load so I could tune my PID settings to handle a big load and I wanted to see how the mods would perform to handle a heavy load.

Load was top rack 12x12 ceramic tile wrapped in foil, foil pan and old vent mod vent on rack 2, upside down foil pan on rack 3, and nothing on rack 4 but water pan set under it.

I put Smoker probe clipped under top rack with a probe 1 backing it up sitting at rack level on top.

I then put probes 2 and 3 on the next two racks on the left side.

I used my Thermopro TP20 to measure right side of racks 3 and 4 at bottom but on the right side.

The simulated load made for quite a bit of load on rack 2 compared to all others.













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What I found was that between racks 2-4 I had temps within 15 degrees of each other.

On rack 1 the discrepency was very large like 50 degrees.  I don't think air could flow much around the heavy load on rack 2.  Even with the fan mod going full blast.

*Heavy Load Test Findings:*

Racks 2-4 behaved well with temps so I think the fan was doing it's job circulating between racks of sensible load
Racks 2-4 had no problem getting to the set temp or close within about 7 degrees
Racks 2-4 I had temps within one another with the largest spread being 15F degrees while trying to reach 325F.  I used 325F for tuning purposes
Rack 1 had a 50F degree lower difference from the highest measurement of the other probes on racks 2-4 :(
With this much load I don't think any level of fan circulation matters because flow is simply blocked all over the place
Hitting the set temp took FOREVER with the vent wide up. Again the load plaid a big part in this
When set temp was hit and the HeaterMeter (HM) would cut/reduce power to the heating element the temp drop would occur and shoot down 20 degrees low and take a long time to pick back up.  I had to PID tune a bit but didn't get to tune as much as I would have liked to, I'll get to that later.
Testing was cut short, explained next.
My testing and tuning was cut short at about the 4 hour mark due to the on/off power switch of my controller box failing.  One of the spade connectors to the on off switch to my controller box appears to have been a little loose because the resistance caused the area to heat up and the switch to start melting.  I stopped when I found this.

Luckily I had ordered 2 witches because it was the same price as ordering 1 switch from a different vendor.  I figured I would have it as a back up in case I broke it during instulation or something bad happened to the switch.  It was a great idea :)

I replaced the switch but could not continue testing until today.

So today I ran a more realistic test.  I put 4 pounds of boneless skinless chicken breast (BSCB) on the top rack and a whole 5.25 pound chicken on a chicken roasting rack set on/in a foil pan all on the bottom (4th) rack.  No water pan.  I put the smoker probe all the way at the ceiling/top of the smoker, it was not on a rack at all.

I backed up the smoker probe with probe 1 of the HM.  Probes 2 and 3 were stuck in chicken breast, one in the middle back of the top rack and one in the middle front of the top rack.

I used the TP20 to measure IT of the whole chicken (in deepest part of the brest), and the second probe to measure temp at rack level of the chicken.

*Realistic Test, Findings:*

Temp discrepency of smoker probe to TP20 rack level probe was about 35F degrees with the smoker probe being the low one
Temp discrepency of smoker probe to HM probe 1 was 10F degrees, with probe 1 being the low one
With the smoker empty and the vent closed I hit a set temp of 335F in about 30 minutes!  I set higher to try and compensate for the drop when I open the door to put chicken in.
When the smoker is empty and vent closed the HM can handle keeping temp very well and recover quickly as well.  See HM dashboard image below.  The red line is set temp.  The orange line is smoker probe and notice it is oscillating within 2 degrees of set temp when things are empty.
I have some inconclusive findings when loaded because I opened the smoker and had a 4-5 minute period of the element cut off :(
There is a HM setting that cuts the power to the heating element off when it detects "lid open" of the smoker.  In a charcoal smoker this is desired because u don't want to turn the fan full blast when the lid is open, only after it is closed.  In an electric smoker this is no good because the heating source is dropping temp not just the air inside the smoker.
I fixed the setting but the damage was done with the temp dropping all the way to 223F :(

Again with load the smoker takes a LONG time building temp back up, keeping the vent closed is a must!
Rack 1 never hit set temp again but the rack was mostly full of chicken breast and it seems the airflow all the way to rack 1 is not so great, even with the fan mod.
The smoker probe on the ceiling was always 10-12F degrees lower which proves air flow at the exact level of a chicken breast is hindered but above the exact rack level it is better
Rack 4 eventually hit set temp but also took a long time to recover over 100F degrees from the drastic drop to 223F :(
The smoke probe on the ceiling and probe at rack 1 level seemed to recover temp at 30-35F an hour while the probe at rack 4 level seemed to recover at about 65F an hour.  This again leads me to believe that the fan is really working well in the area of rack 2-4
I think the MES size and lack of natural airflow related to heating element output is probably a bigger hurdle to overcome than people realize.  It is Definitely something I'm learning about first hand. When rack 1 has a considerable load it seems the space between racks 2-4 behave much much better with airflow and temp.
IMPORTANT, for the first time ever I produced CRISPY skin on chicken in my MES!!!!!  I think the key factors are:
I can get over 300F with the HM controller
The fan does a great job at rack 4 level for moving heat and air around

I had the best smoke flavor I've ever had on chicken, I think the 90% closed vent helped since I had to try and recover temp that way
So in all I think I have a whole new smoker to figure out as is evident by me discovering the impact of the "open lid" setting causing a 100F plus drop in smoker temp hahahaha.

I think the Fan mod is making a difference on lower racks, especially 3 and 4.

I think I am going to abandon using rack 1 unless it is something that cooks quickly like veggies or chicken breast.

I think that no matter the controller that with an MES you cannot get away from needing/wanting to set your temp 20F higher than what you want to cook at so the smoker can better recover from the temp drop od adding the meat to the smoker.  I was doing this before any of the new mods.

I think that during a 5+ hour smoke the recovery to the set temp becomes less of an issue because low and slow is still low and slow whether its climb from 225F to 275F hahahaha.

I think I have eliminated temp swings of 35F with my new setup!!!!

I think I am now poised to smoke sausage and bacon without worry of temp swings to cause fat out or rendering.  This was a major driving factor for me to use a different controller!

I'm getting to where I want to be, I just need more time and smokes.  As is the case with anything worth learning :)

And now if I havent bored you to death, the QVIEW on the best smoked chicken I have ever produced or eaten!!!

BSCB mmmmm!













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__ tallbm
__ May 6, 2017






Crispy skin whole chicken deboned and broken down... and a few pieces missing from what I HAD to eat while deboning :D













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__ May 6, 2017






Screenshot of the HeaterMeter (HM) dasbhoard after the smoke was done.  I just zoomed in on an early portion of the overall timeline where I opened the smoker, added the chicken and all probes.  Hence the orange line (smoker probe) taking a dip and the green line (probe 1 backing up smoker probe) climbing fast.  

The BIG numbers in the image are the last real time values recorded at the time when I shut off the HM.  I had pulled the probes out the meat or moved them them on the rack hence all the different high numbers being measured and reported.
The little box on the graph reports the probe measurements at that time during the smoke/cook.













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__ tallbm
__ May 6, 2017


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## papacurtis (May 7, 2017)

Seriously impressed with your engineering skill set Tall. I have been away from this forum for a long time due to some health issues, but glad i came back to follow this thread. Keep doing what you do cuz i find it fascinating.


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## johnnyb54 (May 7, 2017)

TallBM, I'm curious to know what wattage is your heating element. My 40" MES has a 1200 watt element. On a cold day 35-40 degrees my recovery time after loading food is around 20-25 min. Did you calibrate your probes using boiling water or an ice bath just to make sure all probes read the same? Another thing I noticed, it looks like your using a meat probe to measure ambient temperature. A meat probe only measures temp at the tip while a ambient probe uses the length of the probe to measure. Is it possible the tip of probe on rack 1 was blocked somewhere? Very interesting mod and will continue to follow. Good luck!


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## tallbm (May 7, 2017)

PapaCurtis said:


> Seriously impressed with your engineering skill set Tall. I have been away from this forum for a long time due to some health issues, but glad i came back to follow this thread. Keep doing what you do cuz i find it fascinating.


Thanks, I'll do what I can :)


johnnyb54 said:


> TallBM, I'm curious to know what wattage is your heating element. My 40" MES has a 1200 watt element. On a cold day 35-40 degrees my recovery time after loading food is around 20-25 min. Did you calibrate your probes using boiling water or an ice bath just to make sure all probes read the same? Another thing I noticed, it looks like your using a meat probe to measure ambient temperature. A meat probe only measures temp at the tip while a ambient probe uses the length of the probe to measure. Is it possible the tip of probe on rack 1 was blocked somewhere? Very interesting mod and will continue to follow. Good luck!


I have the 1200watt element and nothing else running on the outlet.  Now there may be other stuff running on the breaker so that might be something but I can't change outlets so I'm stuck there.

I measured all the HM probes and the TP20 probes in boiling water twice.  The HM Probes were the following:

HM Smoker Probe - was 216F (4 degrees high)
HM Probe 1 -3 were 207F (5 degrees low)
TP20 probes were 211F (1 degree low)
The HM allows me to set offsetts so I corrected all the smoker probe with a -4 offset and the others were +5 offset.  I can't fix the TP20 probes but I can live with a -1 degree discrepency.

The HM probes are hybrid Maverick ET732 hybrid probes so they are suppose to work for both.  The TP20 probes are also hybrid probes.

I believe the tip of the probe on rack 1 was blocked somewhat as it was behind a breast fillet and the wall and just a hair above rack level. I put it through a cork and it barely keeps it above the rack bars without touching.  I need to get some clips for sure to raise it an inch or 2.

I look forward to learning more and sharing.  It is definitely cool stuff.  I am still debating on opening up a port on my router to allow the app to work from anywhere rather than when I'm just on my router's wifi.  I will debate that as I worry about the main funtionality getting ironed out :)


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## radioguy (May 7, 2017)

Tall,

I just rebuilt a Smoke hollow electric using a HeaterMeter 4.2. You can do better by, tweaking PID and  fan (SSR) controls. The first temp overshoot was 20-30 degees. I've got that down to 15 degrees...then it settles right in at set temp.  Driving a SSR from that PWM fan out is a bit trickey.  SSR turns on at 3 volts...no reason to drive it with 12volts, fan min 100%, fan max 100%.  I have mine set 40% / 40%. You can read PID tuning at that other website.  I have some more work on mine.  I built the control box and it's a little too small. Have to move it to a biggerbox.

Here's a shot of a pork butt cook....on at 8pm, turned temp down at midnight and went to bed.  I did port forward on the home router...works great.  Now I can control it from the beer store!.

Good luck! 

RG













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__ radioguy
__ May 7, 2017


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## tallbm (May 7, 2017)

RadioGuy said:


> Tall,
> 
> I just rebuilt a Smoke hollow electric using a HeaterMeter 4.2. You can do better by, tweaking PID and fan (SSR) controls. The first temp overshoot was 20-30 degees. I've got that down to 15 degrees...then it settles right in at set temp. Driving a SSR from that PWM fan out is a bit trickey. SSR turns on at 3 volts...no reason to drive it with 12volts, fan min 100%, fan max 100%. I have mine set 40% / 40%. You can read PID tuning at that other website. I have some more work on mine. I built the control box and it's a little too small. Have to move it to a biggerbox.
> 
> ...


Hi RG, thanks for the input!

Good point on the 3volts vs 12 volts.

My PID settings were taken from an Auber PID autotune I did on a different MES I bought for $40 and rewired as a gift to my mother.  

My first temp overshoot is 2 degrees so far using the PID settings I copied from the Auber PID autotune.  When empty the temp oscillates no more than 3 degrees.

My biggest issue is that when I add any decent load to the smoker the recovery time when I open the door takes a while when I have the smoker probe at rack 1 level or higher in the smoker.

Also I discovered that the "lid open" setting needs to be set to 0%.  With an electric smoker it wants to cut output for 240 seconds by default when triggered.  This is NOOOO good lol.  I lost 100F degrees due to that setting.  I'll know how it recovers from a 30F or so drop soon but a 100F drop with 2 racks of food was a killer.

This is fun stuff and I look forward to sharing any info I gather with you :)


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## tallbm (May 8, 2017)

RadioGuy said:


> Tall,
> 
> I just rebuilt a Smoke hollow electric using a HeaterMeter 4.2. You can do better by, tweaking PID and fan (SSR) controls. The first temp overshoot was 20-30 degees. I've got that down to 15 degrees...then it settles right in at set temp. Driving a SSR from that PWM fan out is a bit trickey. SSR turns on at 3 volts...no reason to drive it with 12volts, fan min 100%, fan max 100%. I have mine set 40% / 40%. You can read PID tuning at that other website. I have some more work on mine. I built the control box and it's a little too small. Have to move it to a biggerbox.
> 
> ...


RG have you done anything special for security while opening up a port on your router?

I'm thinking I would:

definitely beef up my router password
use some non standard port number to avoid any bad traffic written specifically for commonly used ports (80, 22, 443, etc.)
Any thoughts on an RSA SSL setup with certificates?  Like have you dug into it much to even know if it is possible with the PitDroid app?

I don't have any concern about a hacker messing with my smoker.  I'm more concerned about them getting to the HM linux system and being able to back track to my router or remote around my network from there.

Feel free to PM me if you don't want to publicly post about your setup.  Thanks!


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## BGKYSmoker (May 8, 2017)

Thanks Dave for finding that.

The Bradley was bad for hot and cold spots. The fan ran CCW and pushed air into the cabinet. I ran my Bradleys with an Auber PID. Did them so much that Auber rebuilt them 6 times. I switched from Bradley back to MES again and still MES POJ. All the $ i spent i went with a better smoker. TSM 30lb. 0 issues.


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## tallbm (May 8, 2017)

nepas said:


> Thanks Dave for finding that.
> 
> The Bradley was bad for hot and cold spots. The fan ran CCW and pushed air into the cabinet. I ran my Bradleys with an Auber PID. Did them so much that Auber rebuilt them 6 times. I switched from Bradley back to MES again and still MES POJ. All the $ i spent i went with a better smoker. TSM 30lb. 0 issues.


Thanks for the info Nepas.  I could see myself going to a different brand someday when all of this wears out.... unless I really fall in love with the HeaterMeter or something lol :)


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## daveomak (May 8, 2017)

nepas said:


> _*Thanks Dave for finding that.*_
> 
> The Bradley was bad for hot and cold spots. The fan ran CCW and pushed air into the cabinet. I ran my Bradleys with an Auber PID. Did them so much that Auber rebuilt them 6 times. I switched from Bradley back to MES again and still MES POJ. All the $ i spent i went with a better smoker. TSM 30lb. 0 issues.


I got lucky...   Now if I could only remember where I put my cocktail down...     
	

	
	
		
		



		
			






  ...    
	

	
	
		
		



		
		
	


	





  ......


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## BGKYSmoker (May 8, 2017)

DaveOmak said:


> I got lucky...   Now if I could only remember where I put my cocktail down...
> 
> 
> 
> ...


I think i did that yesterday.













tcup4.jpg



__ BGKYSmoker
__ May 8, 2017


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## radioguy (May 10, 2017)

TallBM said:


> RG have you done anything special for security while opening up a port on your router?
> 
> I'm thinking I would:
> 
> ...


Doing port forwarding is not truly opening up a hole in your network.  You have to trust your firewalls and password complexity.   Don't skimp on firewall software.  Adding RSA makes it much more complex, it would require a lot more work in the software.  I'm not sure about PitDroid supporting SSH.   You need a public IP / URL address for internet DNS.   I signed up for a "free' one at No-IP.  There are a bunch of services out there.  No-IP offers a free one that you have to renew every 30 days and tolerate their emails to upgrade to a paid account.   The IP service will supply you with a URL (advertised on DNS)  You have some some control over the name.  bbq1.abcd.org for example.  In your home router forward port 80 to your URL.  It mat be pretty easy to set it up for an obscure port number I did not investigate this.  I went one step further and made it MAC dependent.  So only my HM (WiFi adapter) can talk to that web URL.  With it i can use my phone browser or PitDroid APP.  

My electric is truly set and forget. Have Fun!

RG


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## tallbm (May 10, 2017)

RadioGuy said:


> Doing port forwarding is not truly opening up a hole in your network.  You have to trust your firewalls and password complexity.   Don't skimp on firewall software.  Adding RSA makes it much more complex, it would require a lot more work in the software.  I'm not sure about PitDroid supporting SSH.   You need a public IP / URL address for internet DNS.   I signed up for a "free' one at No-IP.  There are a bunch of services out there.  No-IP offers a free one that you have to renew every 30 days and tolerate their emails to upgrade to a paid account.   The IP service will supply you with a URL (advertised on DNS)  You have some some control over the name.  bbq1.abcd.org for example.  In your home router forward port 80 to your URL.  It mat be pretty easy to set it up for an obscure port number I did not investigate this.  I went one step further and made it MAC dependent.  So only my HM (WiFi adapter) can talk to that web URL.  With it i can use my phone browser or PitDroid APP.
> 
> My electric is truly set and forget. Have Fun!
> 
> RG


Yep all that info seems to fall in line with what I have read/researched.

I was eyeballing Duck DNS for a free DNS but saw were many used and reported the same things as you have about No-IP.

I also did not find much in the way of setting up SSH and such and I don't think PitDroid supports it.  I don't want to write my own app just for that because that would be a whole other project to start on but who knows I may just do it.  It would be a good reason for me to play around with mobile app development which I lack experience in.

I guess if I take the steps to expose my HM over the internet I need to go ahead and update my Router firmware and then look into some simple software firewalls for both the HM and my PC's on the network.

As for using an obscure port number, I found information on how to do that.  It all seemed very straight forward is just a few commands to the HM to run things on a different port and a couple of reboots or so and things should be ready to go.

The last thing I was looking to do was to get a smart plug so I could then have TRUE remote on/off capabilities but I think that is probably overkill in the grand scheme of things hahahha.  The idea of getting on my phone while at the grocery store and turning on my smoker seems very appealing but in all practicality I can just turn the smoker on after I walk in the door at home and then go mess with meat and it should be up to temp within the 30 minutes of me unpacking groceries, prepping meat and starting the AMNPS.

Anyhow, thanks for all the info.  I may have some time here in June to do whatever I can think of :)


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## radioguy (May 10, 2017)

When the set point is at zero its virtually off, but not really.   Check this out, all it needs is 3-60vdc from the RPi. 

https://www.adafruit.com/product/2935

RG


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## tallbm (May 10, 2017)

RadioGuy said:


> When the set point is at zero its virtually off, but not really.   Check this out, all it needs is 3-60vdc from the RPi.
> 
> https://www.adafruit.com/product/2935
> 
> RG


Very interesting!


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## tallbm (May 15, 2017)

UPDATE:

So I did a smoke this weekend and I was able to work on the tuning of the HeaterMeter (HM) PID controller.  I think I have it dialed in but it took some values I wouldn't have been able to guess at and may seem a bit extreme.  That is why am posting the pic of the tuning and smoke below to back up my findings! :)

These electric smokers are slow performing systems compared to other systems that PID controllers seemed to be used with.  This means I had to turn things up for very fast response times.  Every second the heating element is off can result in many degrees in change.

So in all I started out with my "P" (Proportional) doing well and not overshooting by more than about 5 degrees.  The settle temp though was more like 12 degrees under though.

I tuned the I (Integral) to where "I" was able to get the settle time down to about 7 seconds while the overshoot stayed about 5 degrees over with no real change.  I could not do any better with the "I" setting so I moved on to the "D".

Now is where things got really tuned in.  I began tuning the "D" (Derivative) setting which is based on the RATE of temperature change to trigger the power to switch off/on to the heating element.  So before as the temp would rise quickly and overshoot to 5 degrees above, I was able to tune the "D" to where my overshoot was within 2-2.5 degrees!!!

Also the settle was within 2-2.8 degrees!!!

In all I was able to keep my temp between 272/273 as a low and 277.5 as a high!  Keeping within 3 degrees is aswesome!

When I bumped the temp up to 325F I was able to keep within 320-327 so 2 degrees overshoot and 5 degrees settle.  I can live with that as well.

I thought I had disabled the Lid Open mode but apparently I was wrong so I took another shot at "disabling" it and hopefully I have it resolved once and for all so I don't wind up with the element being shut off for such a long period of time to drop 100F+ degrees!













HmTuning.png



__ tallbm
__ May 15, 2017






I did run into another issue.  I discovered that I am burning up my 2nd On/Off Rocker switch 













warmer-switch-7-8-x-1-1-8-dpst.jpg



__ tallbm
__ May 15, 2017






After doing some reading it seems that the issue may be a few things but mainly that I am having peaks of drawing too much amperage through the switch towards it's upper limit.  My 15A fuse does not blow so I think I am continuously drawing near the upper limit and the switch really doesn't handle it well and melts down after these 5hr+ smokes.

I'm going to simply bypass the switch and my On/Off will be when I plug or unplug the controller.

The alternative would be to step down the voltage and amperage to the switch and then run another Relay like the SSR where the switch then sends the lower voltage signal to the SSR to allow the real power to flow through when I flip the switch.

This is way more than I really want to do so I'm just going to eliminate the switch and my a plug/unplug will do the job lol.

Anyhow thats what I've got for now.  I'll continue to post updates as I come across more findings.  Once everything has settled down I plan to do a step by step post for a HeaterMeter PID job with components needed like SSR, wires, wifi adapter, etc. as well as the HM PID settings, lid open mode settings, etc. etc.


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## johnmeyer (May 16, 2017)

The problem with the switch may be caused by the "inrush" current when a heating element is first turned on. This is a fairly typical problem. It's been a long time since I spec'd switches, but you might look for ones that are designed for inductive loads (like motors). A second thing you can do is to put a 250V *non*-electrolytic capacitor of at least 0.1 uF directly across the switch. It will help absorb some of the inrush current and reduce the arcing across the switch contacts, which is probably what is causing the switch to self-destruct. Finally, you can simply "derate" the swtich, which means getting one that has much higher specs than called for. This is a typical engineering solution, where you design in a buffer.

I'm sure there are thousands of articles about this, but a quick Google search turned up this one. Just skim the first page.

Switch Ratings, What's it all Mean?

It is for airplane switches (they typically use 24V), but the same principles apply to what you're doing.

[edit] Here's a derating calculator for switches. You'll want to use the "lamp load" column, because the MES heating element is basically the same thing (electrically) as a big incandescent light bulb:

Rerating Current For Switches With 125v AC Original Ratings

As you can see, you'll need a switch that has between 3 and 5 times the current capacity as the steady-state current. For a 1,200 watt heading element, the current is nominally 10 amps, so you would need a 30 to 50 amp switch.


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## tallbm (May 16, 2017)

johnmeyer said:


> The problem with the switch may be caused by the "inrush" current when a heating element is first turned on. This is a fairly typical problem. It's been a long time since I spec'd switches, but you might look for ones that are designed for inductive loads (like motors). A second thing you can do is to put a 250V *non*-electrolytic capacitor of at least 0.1 uF directly across the switch. It will help absorb some of the inrush current and reduce the arcing across the switch contacts, which is probably what is causing the switch to self-destruct. Finally, you can simply "derate" the swtich, which means getting one that has much higher specs than called for. This is a typical engineering solution, where you design in a buffer.
> 
> I'm sure there are thousands of articles about this, but a quick Google search turned up this one. Just skim the first page.
> 
> ...


Thanks johnmeyer, that all makes sense!

I found some marine single pole breaker toggle switches by Blue Sea Systems that should do the trick.  I can find switches in all kinds of AC Amperage ratings and go up to the 100A for 125V AC switch if want.  The 100A trips at 67.5A.    It should also fit in my controller box as well which would be a huge win.













61N-5Dgx6BL._SX522_.jpg



__ tallbm
__ May 16, 2017






Also do you feel it would be wise to upgrade the wire that connects to this switch to be 10AWG? 

Thanks for the info.


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## radioguy (May 17, 2017)

Johnmeyer,  I have to respectfully disagree with you comment on "In-rush" current.  Heating elements are resistive, their load is constant.  The resistive value may vary a slight bit due to temperature change, has to do with what they are made with.  In rush current only occurs on inductive or capacitive loads IE motors, coils.

What is killing the switch is the continuous duty, duty cycle.  Those cheap Chino switches don't cut it in a constant high amperage application.  The materials used are inferior, contacts heat up, casing more resistance, more heat and so on.  What you need is a bad a$$ switch made in the USA.   You are only switching 1200watts (mine is 1500).  That is a one time switch per use.  The SSR takes over from there.  Your current through the switch will vary from 0 to about 10amps.  It will be 10amps for nearly 100% of the time at the start but the duty cycle will decrease as you reach set temp.  Once at set temp, duty cycle should be at it lowest (per set temp), I hope that makes sense.  I'm using a similar switch in mine 1500 watts, removed from some old equipment dated 1962, about 20 hours of usage no problems.  

Glad to see you got it tuned in better.  Are you using a thermo couple for pit probe?  I decided not to try and save and bought some good quality TC and RTD from ThermoWorks.  

Happy Smokin'

RG













0517170912.jpg



__ radioguy
__ May 17, 2017


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## tallbm (May 17, 2017)

RadioGuy said:


> Johnmeyer,  I have to respectfully disagree with you comment on "In-rush" current.  Heating elements are resistive, their load is constant.  The resistive value may vary a slight bit due to temperature change, has to do with what they are made with.  In rush current only occurs on inductive or capacitive loads IE motors, coils.
> 
> What is killing the switch is the continuous duty, duty cycle.  Those cheap Chino switches don't cut it in a constant high amperage application.  The materials used are inferior, contacts heat up, casing more resistance, more heat and so on.  What you need is a bad a$$ switch made in the USA.   You are only switching 1200watts (mine is 1500).  That is a one time switch per use.  The SSR takes over from there.  Your current through the switch will vary from 0 to about 10amps.  It will be 10amps for nearly 100% of the time at the start but the duty cycle will decrease as you reach set temp.  Once at set temp, duty cycle should be at it lowest (per set temp), I hope that makes sense.  I'm using a similar switch in mine 1500 watts, removed from some old equipment dated 1962, about 20 hours of usage no problems.
> 
> ...


Hi RG thanks for that input as well.

I ordered that 100A marine switch breaker so I should be covered for continuous duty, inrush, or anything short of a lightning strike :P

My pit probe is a K Type Thermocouple (TC).  The HeaterMeter (HM) I bought is created for 1 TC and 3 Maverick 732-3 hybrid Thermisters. 

I tested all probes twice in boiling water.  I had to wrap the TC in a plastic sandwich bag to waterproof it. 

Test 1 was to see what the probes were reading.  The TC was 4F high and the other probes 5 degrees low.  I then set the offsets for the probes in my HM and retested.  With Test 2, everything was spot on to 212F in the boiling water :)

I just looked at the Thermoworks TC's and I have my eye on one of the two alligator clip ones should this TC fail.  I know the one I bought from Auber may be more cheaply made.  Whomever assembled it decided it was a good idea to twist the slack out of the two wires that get screwed down to the prongs in the yellow case.  This meant it always read 80F.   I had to undo the yellow case, untwist the wires, spread them, tape them off with electrical tape for "insualtion" and then screw them back down.  The probe worked properly after that. 

As for now I'm try and work all the kinks out before I do any additional tweaking.

Oh, by the way.  After I had dialed in the P-I-D values I decided to switch the fan to 40% output like you suggested.  After there the change the temp quickly creeped up to over 280F and continued upward on a 275F set point.  One or more of the P-I-D tunings seems to take into account the output percentage because 4V vs 12V output should make no difference for the SSR to switch off and on and cause the heating element to receive any more or less power.. 

Since the HM is designed for a blower fan my guess is that the P-I-D logic/calculations take the fan output into consideration and resulted in my temp creep. 

I think the Derivative (D) was affected most by the change in fan output because I turned the output back to 100% and it didn't recover.  Only after I turned the D back to 0 did the temp stop climbing.  Once the temp was back in the valley of the P-I cycle from before did I set the D back to the working settings and sure enough I was back in my tight loop.

This was an interesting learning experience with the fan output lol.  For now I'm going to leave the output at 100% and simply waste the extra 8V of the 12V being sent to switch the SSR lol.


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## johnmeyer (May 17, 2017)

RadioGuy said:


> Johnmeyer,  I have to respectfully disagree with you comment on "In-rush" current.  Heating elements are resistive, their load is constant.  The resistive value may vary a slight bit due to temperature change, has to do with what they are made with.  In rush current only occurs on inductive or capacitive loads IE motors, coils.


You are correct that the higher startup current for an inductive motor is causes by not having "back EMF" from the motor when it first starts and is not turning. Once turning, the current drops because the magnetic fields in the motor reduce the current. However, for a lamp or heating element there is also a much higher initial current because the resistance (as opposed to impedance) changes substantially as the element heats. It is not a small change. You can prove this by measuring the resistance of a common incandescent light bulb with a common ohmmeter. If you plug that resistance into an ohm's law calculator, it will predict a current, and a wattage, that is way higher than what the bulb actually consumes.

But you are probably correct that the word "inrush" may not be the correct one to describe this initially higher current.

Regardless of what you call it, the additional initial current does need to be taken into account when specifying the switch.


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## tiros (Jun 5, 2017)

> I think the "no back removal" MES rewire tips will be super helpful and I will include the measurements for adding a back panel for the Rollout Limit Safety switch, which I did not show in the pics above.  I swapped mine with a 350F manually resetable switch and used high temp steel connectors.  I don't like the idea of the one time use 302F switch being there without me being able to access it.  Plus the higher 350F threshold will give me some margin for error as I manually tune my HeaterMeter PID to get things heating properly.
> 
> I hope you enjoyed and thanks for stopping by!


Are you saying here the over temp limit is one use?

I thought they reset when they cool down...Can you verify as I am currently experimenting with designing a new controller.


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## tallbm (Jun 5, 2017)

Tiros said:


> Are you saying here the over temp limit is one use?
> 
> I thought they reset when they cool down...Can you verify as I am currently experimenting with designing a new controller.


Hi there and welcome!

I cannot 100% verify but recently a couple of other reputable members claimed they were auto reset.  I believe on of them may have even found the exact replacement on Amazon.

I would say I am about 95% confident in the information from these other members.

I will go back and fix the info in that post to make sure it highlights that the rollout limit switch is more than likely an auto reset type.

Let me know if you have any other questions and best of luck on the controller design :)


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## dr k (Jun 5, 2017)

Tiros said:


> Are you saying here the over temp limit is one use?
> I thought they reset when they cool down...Can you verify as I am currently experimenting with designing a new controller.


The safety snap disk sensor resets itself per DaveOmak. Unless it's damaged/defective. 
-Kurt


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## tallbm (Jun 5, 2017)

I still think it is a good idea to make a panel to access the Rollout limit switch as it's connectors are one of the known week spots in the MES wiring circuit.  This way you can easily access and repair/swap the Rollout limit switch when the connectors corrode away... and it seems they almost always do.

I replaced my connectors with Hi Temp stainless steel ones at both the Rollout limit switch and the heating element sites.  I think I will be good to go for a while without corroding connectors :)


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## tallbm (Jun 12, 2017)

UPDATE:   So after two sausage smokes, 2 pastrami loaf smokes, 1 pork butt, and a whole chicken smoke I feel like I have discovered and confirmed my HeaterMeter PID tunings!

My new 100 Amp On/Off breaker switch I used to replace the cheapo Chinese melting On/Off rocker switches has showed no issues and worked like a champ, so that issue has been ironed out!

The convection fan mod is still working strong and the flipping of the heating element has shown no issues, so those mods are still good to go.

I now feel good posting about any of the mods I have made individually so others can understand and apply the mods for themselves if they like.

This is been a fun adventure and was really a challenge to get the HeaterMeter PID tunings figured out as well as figure out some of the other uncommon mods and their quirks.

I hope I can get some posting about these mods this week :)

Steady HeaterMeter Smoker Temps (see the orange line for main smoker probe, and light green line for back up smoker probe):













ptunes.png



__ tallbm
__ Jun 12, 2017


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## madtownmonkey (Jun 19, 2017)

I just got a heater meter kit for fathers' day. I am wondering if anyone has tried to control the MES 40 bluetooth through the control panel connections? I would think there has to be a wire to an exiting relay.

I'd be really interested to see how you've configured heater meter to get good temp control.


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## tallbm (Jun 19, 2017)

madtownmonkey said:


> I just got a heater meter kit for fathers' day. I am wondering if anyone has tried to control the MES 40 bluetooth through the control panel connections? I would think there has to be a wire to an exiting relay.
> 
> I'd be really interested to see how you've configured heater meter to get good temp control.


Hi there and welcome!

I kind of had that same idea as well early on but I passed on it because there were just too many unknowns with the electrical circuit board at the bottom of the MES.

In theory you can use a Multimeter to determine to which wires are running power vs the control signal to the solid state relay, you should also be able to tell if the current is 110v or 12V (HeaterMeter needs 12V and over 2Amps).  There may be also be resisters and other stuff in the mix on that board, I'm not sure. 

I simply rewired my MES to take the electricity from the plug and go to the heating element while still including the rollout safety switch in the mix.  

My HeaterMeter sends a control signal to a Solid State Relay (SSR) which allows power to run to my rewired MES chord.  The power to the MES heats up the element.  

There is a probe from the HeaterMeter that is inside the MES that measures temp.  The probe and the HeaterMeter will then turn on/off the control signal depending on the set temp and what the probe is reading.  The power is then cut off/on to the MES heating element.

That is it in a nutshell :)


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