How I wired a PID to control temperature

[6bg6ga]

The PID control device allows one to do a number of things from one some what simple little electronic box. My bullet caster now turns on the cooling fans via the Mypin PID control unit automatically. It just takes a little extra wiring and programing to do so. I will point out that as the load on a SS relay increases so does the heat output from the SS relay thus the need for adequate heatsinking. The heat sinking and removal of heat IS necessary in order to maintain an adequate invironment for the PID control unit. In other words don't heat sink the SS relay in a small box that also contain the PID because you could end up with the temperature of the box going too high and thus the destruction of the PID unit.
While you may not notice any heat when the SS relay is controlling say a 300 watt heater you will certainly notice the heat when controlling say a 2000 watt heating element.

[nodda duma]

Very cool

[rattletrap1970]

This is the one I built:

[Garyshome]

I got all the stuff just have to get after it. Thanks for the post!

[Uptickk]

Thanks 6bg6ga! Very informative. I might have some follow up depending on which way I go.

Thanks again!

[el34]

This is the one I built:

Very well done.

[6bg6ga]

Very well done.

I can't see the area around the SS relay but I will add this. If you didn't use heat sink compound to the back of the SS relay I would advise you doing so. A THIN layer of this helps to transfer the heat from the relay to the aluminum. Now, you do have a nice area/ amount of aluminum there to take heat away from the relay. As long as the temperature where the PID control is mounted does not hit 125 degrees or more the PID will live a long life.

[6bg6ga]

Thanks 6bg6ga! Very informative. I might have some follow up depending on which way I go.

Thanks again!

I just wanted to answer your questions and offer an alternative way (old school way) of doing it. Sometimes trying to put a SS relay in a small electrical box with the PID just builds up too much heat.

With mine I can provide the power for my relay control and also power a counter with the same supply. This comes in handy if you wish to have a rough idea of the number you have produced. This works well with the bullet sizers and also some bullet casting machines like the Ballisti-cast Mark IV, X or the Magma bullet caster.

[magnetik]

just finished mine.. fun little project. thanks to all the posters who posted diy's like this one. tried to jam everything in the medium auberins box but was a little too crammed so I had to rig up the relay on the outside. might try again though then hang a heatsink off the back. wanted to be able to stack two individual rigs on top of each other and maybe use some pc power supply power supply type jacks to allow me to pack them without cables hanging off of it.

[rattletrap1970]

Just finished my fume hood vented to outside.

[joehatzs]

I have a MYPINS T series PID.
I have it set at 210f and works fine.
I now want to raise the temperature to 250f, I can set the desired temperature (sv) to 250f but the recorded temperature (pv) stops at 212f and the unit just keeps on running as it never meets the desired temperature.
I can run it at lower temperature's but will not indicate above 212 in PV.
Is there a reset that I have to do or is my unit faulty.
When i first received it I had it indicating higher temp.
any help would be appreciated.

[nodda duma]

Funny, I actually set out to do this on my own. I hadn't realized PID controllers could be had for so cheap until I searched eBay out of Idle curiosity. When I saw they could be had for so cheap I knew I just had to control the temp (I'm an engineer so I'm naturally slightly OCD). I have a Lee 4-20 Pot

I didn't even think to check the cast boolit forum until after I had ordered parts and had them on the way (tagged the thread up above when I found it).

I bought a mypin controller & ssr kit, with the difference from this post being I ordered a j-type thermocouple. Wired mine up to just plug the melting pot in through the controller. Put everything in a cardboard box since that's what I had available. Don't worry I taped it shut so I wouldn't open it while it was running!

Once I found this thread (after I got it running lol), I did adopt the idea above to solder the thermocouple up thru the bottom to read the temperature near the spigot.

Here is "first heat" before drilling thru the bottom.



Total cost was about $40.

[Uptickk]

If I am trying to mimic this setup for 220v and two 1500watt heaters is it recommended that I used two 25amp SSRs, one for each heater? One should do the trick since combined I am dealing with ~13.6amps but wanted to consult the brain-trust first.

Thanks

This is how I wired my temperature controller:

Items purchased from http://auberins.com/

Universal 1/16 DIN PID Temperature Controller http://auberins.com/index.php?main_p...products_id=90
25 amp SSR (solid state relay) http://auberins.com/index.php?main_p...&products_id=9
Heat sink for SSR (will help maximize the life of the SSR) http://auberins.com/index.php?main_p...products_id=45
K type thermocouple high temperature http://auberins.com/index.php?main_p...products_id=22

Item purchased or supplied locally:

Crimp on wire connectors, spade type
Short heavy duty extension cord – my Lee pot has a 2 conductor plug and is not grounded, so the my wiring does not include a ground as nothing in the wiring needs it.
Small amount of extra wire for jumpers
Terminal wiring block. Mine has 2 rows of 4 screws. Available in the automotive section.

Procedure:
1) Mount terminal block to base
2) Cut extension cord in half. Strip wires and crimp in spade terminals.
3) Attach 2 modified cords to one side of terminal block in order from left to right---
a. Outlet black | outlet white | plug white | plug black
b. This is the inlet/outlet side of the terminal block, the other row is all for internal connections. The Outlet refers to the end of the cord you will plug the casting pot into.
4) Mount SSR to heat sink and mount this assembly to the base. Don't forget to put a dab of the white heatsink grease on the back of the SSR before you attach it.
5) Wire T1 of SSR to screw terminal across from Black Plug Wire
6) Wire L1 of SSR to screw terminal across from Black Outlet wire
7) Install a short jumper wire from screw terminal across from White Outlet Wire to screw terminal across from White plug Wire
8) Mount PID controller to base
9) Run a pair of wires from screws across from White Plug Wire and the Black Plug Wire to PID AC/DC input contacts 1 and 2 on my controller, polarity does NOT matter with AC power
10) Run a wire from PID SSR+ (contact #6) to SSR A1+
11) Run a wire from PID SSR- (contact #7) to SSR A2-
12) Connect the thermocouple to PID TC (contacts 9 and 10)

I wanted to add some pictures but haven't figured out how to do that.

[igolfat8]

What gauge wire is needed for all of the wiring?

[Jeff Maney]

I made a small metal bracket and mounted my T/C about 1/2" from the bottom & 1/2" from the side of the pot, just out of the way fluxing.
Jeff

[ubetcha]

Can I use Dielectrical grease as heat sink grease? I use this quite often on my job as an auto tech on electrical connectors.

[6bg6ga]

Can I use Dielectrical grease as heat sink grease? I use this quite often on my job as an auto tech on electrical connectors.

No!!

You need to transfer the heat to the heatsink and you need heat sink grease for this. Dielectrical grease seals out moisture. Completely different

[6bg6ga]

Easy to obtain from Rat Shack

Attachment 118914

Less than $4

[ubetcha]

Thanks for the info. I ordered the pid, tc, ssr, and box yesterday. I did not order a heat sink as I understand that if I mount the SSR outside the box using heat sink grease it should keep cool. I do have a small fan near my pot to keep air flowing, so i hope that should work. If I decide to mount inside, I will add cooling hole and move the fan so air flows over the control box

[6bg6ga]

Thanks for the info. I ordered the pid, tc, ssr, and box yesterday. I did not order a heat sink as I understand that if I mount the SSR outside the box using heat sink grease it should keep cool. I do have a small fan near my pot to keep air flowing, so i hope that should work. If I decide to mount inside, I will add cooling hole and move the fan so air flows over the control box

There are things to be considered here....

What is the current draw? What are you running with the PID? How many watts? If the current draw is low and your box is aluminum then there is a possibility of mounting the SSR to the box. If the box isn't aluminum then by all means purchase a heat sink for it. If your running a melting pot then I would say get a heat sink and mount the PID to it and be sure to use heat sink grease. If your running say a heater element for a bullet sizer then you don't need to purchase a heat sink providing the box is aluminum. I can tell you with 100% certainty that a 15A load will need a heat sink and or a fan in order to work.