PID controllers for coils

Haze Mister

Verdant Bloomer
Manufacturer
I searched this forum for "PID controllers" and got nothing so here it is... since more flower-vaping people seem to be using coils now that we have various injector options, this may be a good place to post related questions.

I'll start-

-Does the controller itself get very hot ?

-Graveda's €90 kit has a 2-prong mains plug - i.e. no earth. Does this mean it's not so safe? Other controllers I have seen have the proper 3-pin plug...

-It looks like some controllers can go to higher temperatures than are safe to use with the coils ?

-Some controllers seem to have no auto-power off . If the coil is in a ceramic enclosure and is left on overnight, is there a problem?
 

GratefulDread

Well-Known Member
Have been using the same PID for like 7 years now, never had a single issue leaving it on. I never intentionally leave it on overnight but once in a while I do by accident.. never been an issue. If I had little kids running around or something, I'd probably be more careful though.
My controller doesn't even get warm.
I'd probably try to find one with 3 prongs, which most do. Not sure how important that is though.
 

badbee

Well-Known Member
-Graveda's €90 kit has a 2-prong mains plug - i.e. no earth. Does this mean it's not so safe? Other controllers I have seen have the proper 3-pin plug...
A ground pin is only adding safety if it is connected to a metal housing on the device. If the PID has a fully plastic shell, it doesn't need grounding. In that case the downside is the plastic.
 

Thick Vape

In the Ballpark
I have used 4 different PID's over time.
None of them got warm during use as much as I remember.
All of them have an earth 3 pin plug. So I don't know about 2 pin safety.
One some controllers you can set the upper and lower limits to your preference. This limit appears arbitrary to me. If the coil can reach that temperature is not related to what you set.
One runs 24/7 pretty much all the time for a couple years with no problem. The auto-off one, which switches off a couple times a day, runs since a year or 2 with no problems yet.
 

Haze Mister

Verdant Bloomer
Manufacturer
One runs 24/7 pretty much all the time for a couple years
I see ... username checks out!! :smug:

What I was trying to work out is whether a malfunction of some kind could lead to the system not sensing the coil temperature increasing and just carrying on heating until it starts burning. But it sounds like this just doesn't ever happen as the machines are designed to prevent that.
 
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tinctorus

Well-Known Member
Accessory Maker
I got a quick question for the people on this forum, who here would/could use a pid controller that would control 4 coils and show their Temps all from 1 pid
You would have 4 XLR plugs and can turn each channel on/off at will

If this sounds like something you would be interested please let me know, I'll be building them anyways but I'm curious how much if any demand is there for it
 

Curious Gorilla

Sounds like something smells purple.
I searched this forum for "PID controllers" and got nothing so here it is... since more flower-vaping people seem to be using coils now that we have various injector options, this may be a good place to post related questions.

I'll start-

-Does the controller itself get very hot ?

-Graveda's €90 kit has a 2-prong mains plug - i.e. no earth. Does this mean it's not so safe? Other controllers I have seen have the proper 3-pin plug...

-It looks like some controllers can go to higher temperatures than are safe to use with the coils ?

-Some controllers seem to have no auto-power off . If the coil is in a ceramic enclosure and is left on overnight, is there a problem?
The ground pin on the plug not just for the case, the sheath of the hot runner coil is connected to ground/earth too.
Im not sure the pids without an earth connection are meant for our patrticular use.
IF THE HEATING ELEMENT INSIDE THE HOTRUNNER COIL SHEATH CONTACTS THE OUTER METAL SHEATH IT WILL CONDUCT THE 240/110 VOLTS FEEDING THE COIL. EARTH CONNECTION ALOWS THIS TO CONDUCT TO GROUND, instead of through you.
Although unlikely with normal use, this is much more likely if you make your own diy pinky/brain or glass adaptor in a coil, as the coil can be damaged by stretching/bending.
To my understanding.
I would NOT use a PID and hot runner coil without an earth, unless it was runing from low voltage DC.
Please, someone weigh in if im wrong.
I am not an electronic engineer, research it if you are unsure.there is plenty info online.
 

Thick Vape

In the Ballpark
I see ... username checks out!! :smug:

What I was trying to work out is whether a malfunction of some kind could lead to the system not sensing the coil temperature increasing and just carrying on heating until it starts burning. But it sounds like this just doesn't ever happen as the machines are designed to prevent that.
lol. I only use it every couple days now. But pushing that button a little in advance would be far too hard for me.:cool:

I unterstand now.
I tried a burn off and it seems for a certain wattage of the PID/Coil the coil hits an equilibrium at a point where you cannot go hotter without more wattage. When the coil is insulated I imagine it could go hotter.
But then the PID stops at a set temp as you say. At least the good quality ones do., I guess.
If the coil melts I think the PID registers malfunction too.
 

tinctorus

Well-Known Member
Accessory Maker
lol. I only use it every couple days now. But pushing that button a little in advance would be far too hard for me.:cool:

I unterstand now.
I tried a burn off and it seems for a certain wattage of the PID/Coil the coil hits an equilibrium at a point where you cannot go hotter without more wattage. When the coil is insulated I imagine it could go hotter.
But then the PID stops at a set temp as you say. At least the good quality ones do., I guess.
If the coil melts I think the PID registers malfunction too.
Yeah they're pretty safe I've had mine on now for 19 days in a row and counting😂, I'm waiting on 1 to come in for a project that gives rs845 communication so you could monitor your Temps on the computer if you wanted to
 

Thick Vape

In the Ballpark
I got a quick question for the people on this forum, who here would/could use a pid controller that would control 4 coils and show their Temps all from 1 pid
You would have 4 XLR plugs and can turn each channel on/off at will

If this sounds like something you would be interested please let me know, I'll be building them anyways but I'm curious how much if any demand is there for it
I like the idea, but I only see the use for 2 outputs for me.
 
Thick Vape,
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GratefulDread

Well-Known Member
Yeah they're pretty safe I've had mine on now for 19 days in a row and counting😂, I'm waiting on 1 to come in for a project that gives rs845 communication so you could monitor your Temps on the computer if you wanted to
Does the rs845 connection allow you to control it with your PC as well? Or just for monitoring?
 
GratefulDread,

Curious Gorilla

Sounds like something smells purple.
I see ... username checks out!! :smug:

What I was trying to work out is whether a malfunction of some kind could lead to the system not sensing the coil temperature increasing and just carrying on heating until it starts burning. But it sounds like this just doesn't ever happen as the machines are designed to prevent that.
My coil on my diy is only set to 435f but the coil gets red hot while getting to temperature, it overshoots to heatsoak then stabilise, i believe.
Red hot is getting up past 930f. You can also get red hot hot spots if the wire heater element inside the coil sheath is shorting against itself (this is more likely to happen if you stretch/shape/bend you coil around, like when fitting a diy injector head into a coil )

That means you gotta buy more ball vapes 😂😂


Its probably most use to people using PIDS for hot plates for squishing rosin out of buds for dabbing(still havnt tried proper concentrates but have some kief), one day i hope to have many many injector heads. It is a nice idea.
And a v6 style manifold to use them all at once, and a glass engine block waterpipe.
 

tinctorus

Well-Known Member
Accessory Maker
My coil on my diy is only set to 435f but the coil gets red hot while getting to temperature, it overshoots to heatsoak then stabilise, i believe.
Red hot is getting up past 930f. You can also get red hot hot spots if the wire heater element inside the coil sheath is shorting against itself (this is more likely to happen if you stretch/shape/bend you coil around, like when fitting a diy injector head into a coil )




Its probably most use to people using PIDS for hot plates for squishing rosin out of buds for dabbing(still havnt tried proper concentrates but have some kief), one day i hope to have many many injector heads. It is a nice idea.
And a v6 style manifold to use them all at once, and a glass engine block waterpipe.
Hey whatever use a person has it will be great for
@GratefulDread
US $60.00 | 4 Channel Digital Display Thermostat,Multichannel Temperature Control Meter RS485 Communication Record Intelligent PID
 

Haze Mister

Verdant Bloomer
Manufacturer
My coil on my diy is only set to 435f but the coil gets red hot while getting to temperature, it overshoots to heatsoak then stabilise, i believe.
Red hot is getting up past 930f. You can also get red hot hot spots if the wire heater element inside the coil sheath is shorting against itself (this is more likely to happen if you stretch/shape/bend you coil around, like when fitting a diy injector head into a coil )
That's definitely good to know, thanks
 
Haze Mister,

Curious Gorilla

Sounds like something smells purple.
Hey whatever use a person has it will be great for
@GratefulDread
US $60.00 | 4 Channel Digital Display Thermostat,Multichannel Temperature Control Meter RS485 Communication Record Intelligent PID
Looks like Your PID units will be able to be able to be programmed for things like - pre heat step/hold time. heat to first stage temp setting ,first stage hold time , overshoot target temp range? The PID then stabilise down to target. The PID then increases heating as needed acording to thermocouple readings, with a slight overshoot to compensate for a drop in temps(adjustable?), and hysterysis adjustment to alter response time and range to temperature change. Slightly hard to say for sure as i dont read or speak Chinese. That PID is interesting enough to make me wish i did.
Also looks like they Will they be programmable on the units themselves, are there instructions in english?
Nice looking unit.
I know at least some of these things are adjustable on our basic standard single PIDs, accessible through the 'set' and '>' button next to it usually on the far right under the led display, but i dont have a clue how to change them.
If anyone does know how or knows a link to instuctions i would appreciate the info. Will try and find the page for double display(single pids)I found a while back if i dont doze off...wasnt sure it was the same for mine, and didnt feel the need to mess with it at the time.
 
Curious Gorilla,

tinctorus

Well-Known Member
Accessory Maker
Looks like Your PID units will be able to be able to be programmed for things like - pre heat step/hold time. heat to first stage temp setting ,first stage hold time , overshoot target temp range? The PID then stabilise down to target. The PID then increases heating as needed acording to thermocouple readings, with a slight overshoot to compensate for a drop in temps(adjustable?), and hysterysis adjustment to alter response time and range to temperature change. Slightly hard to say for sure as i dont read or speak Chinese. That PID is interesting enough to make me wish i did.
Also looks like they Will they be programmable on the units themselves, are there instructions in english?
Nice looking unit.
I know at least some of these things are adjustable on our basic standard single PIDs, accessible through the 'set' and '>' button next to it usually on the far right under the led display, but i dont have a clue how to change them.
If anyone does know how or knows a link to instuctions i would appreciate the info. Will try and find the page for double display(single pids)I found a while back if i dont doze off...wasnt sure it was the same for mine, and didnt feel the need to mess with it at the time.
@GratefulDread Yeah I'm sure there's quite a few things you could monitor and adjust

Here are the pdf on this page
 
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Cheebsy

Microbe minion
I know at least some of these things are adjustable on our basic standard single PIDs, accessible through the 'set' and '>' button next to it usually on the far right under the led display, but i dont have a clue how to change them.
If anyone does know how or knows a link to instuctions i would appreciate the info.

Here is a thread that might help. It seems like, even if the generic PID has a different model number it be programmed in a similar way. Only good for some generic PIDs.

 

Curious Gorilla

Sounds like something smells purple.
After someone pointed out how low my DIY Balls Up runs at i thought the heater coil may have an issue .
Possibly usefull information for others.....

" "Soft start" the hot runner system. Many heater designs include a compacted magnesium oxide layer that promotes efficient operation but absorbs moisture when idle. When starting the system after an extended period of time, first soft start it at a lower temperature for 30 to 60 minutes for moisture to bake out. That will prevent heater shorts and promote heater life. "
From https://www.plasticstoday.com/tips-help-you-succeed-hot-runners

" Is the temperature bouncing around faster than the steel temperature could realistically be changing? Sometimes the controller will show the temperature zone jump up and down and back up again a hundred degrees in just a couple of seconds. If the temperature movement appears to fast and sporadic to be real it’s usually caused by the TC receiving electrical noise. To correct this, you need to make sure everything is properly grounded.


The thermocouple connector should be grounded to the hot runner or the tool. Both the temperature controller and the injection molding machine must be properly grounded, as well. In some rare cases even if everything is properly grounded you may still see the issue when ungrounded style thermocouples (see previous post for explanation) are used with certain types of temperature controllers. If this is the case you will need to add a ground wire to the negative side of each thermocouple in the connector. To reduce wiring install a jumper connecting all the negative pins of the thermocouple connector and run a wire to ground from the last pin.


Is one zone stabilized well above setpoint? This could point to a pinched thermocouple. Here the thermocouple has been damaged somewhere along its length causing the two wires of the thermocouple to make contact with each other. This often happens when the thermocouple gets trapped between mold plates during installation or is pulled too hard around a sharp corner. In my previous post I discussed how the thermocouple has two junctions. The hot junction at the measuring end and the reference junction within the controller. The pinch point makes a new junction creating a second thermocouple on the same circuit. The reported temperature from a pinched thermocouple will be between the temperature of the hot junction and that of the pinch point.


Pinched TC



Because the pinch point is almost always colder than that of the hot junction the temperature reported to the controller by a pinched thermocouple will be below the temperature at the hot junction. The controller will continue to send more power to that zone until it believes the temperature has reached setpoint, however, when this occurs the actual temperature of the zone will now be far above setpoint. On the temperature controller the overshoot does not show up on the zone with the pinched thermocouple. The overshooting zone will often drive up the temperature of adjacent zones causing them to overshoot setpoint and this will show up on the temperature controller. "

From https://hotrunnerhelp.com/category/hot-runner-troubleshooting/

If nothing else, may help with getting to sleep...
 

Haze Mister

Verdant Bloomer
Manufacturer
i saw the Graveda kit at a local shop and snagged it for less than €80. The case is metal. The buttons are large and clicky, screen and buttons are on the top side rather than the front. It' s easy to understand and use. It briefly gave an error message on first use but no trouble after that.

I like it a lot so far! Mini XLR connector ....but I'm confident they will replace the coil if needed.
I like this company also because of this:


IMG20230320174611.jpg
 
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