Need help wiring a PID controller

[freespirited]

I read the other thread in here and I think I have it down. However, the other thread jumps back and forth between discussions and it throws me off. I would like to hear it directly. Thanks. Heres a list of what I have: an Auber PID #SYL-2362 and 2 Mager MGR-1 D4840 Solid State Relays (control is 3-32vdc, output is 40A/ 24-480vac) mounted to heat sinks inside a 8x8x8 plastic junction box, 10ft of 10-2 wire (to run between the 8x8 box and the keg), another junction box welded to the side of a SS keg, a bung welded inside the box to the keg about 2" off the bottom for a 240v 4500 watt low encoloy element. I have a 4 prong 30amp dryer plug to run from 30a 220v outlet to the 8x8 box containing the SSR's.

As for wiring: I run ea dryer plug hot wire (keep in mind here we have 2-110v hots, a nuetral, and a ground to get 220v ) to an SSR (they have the schematic on them) and hook the ground to the keg, and just leave the nuetral wire nutted? Then I use the dia in the pid manual for the signal to the SSR' s and hook the power/ground to a ac extension cord. The hot on the other side of the SSR, each one goes to the heating element? I have the book for the pid I really just wanted to double check the wiring for the SSR's. I know that I will have to run in manual mode. I just wanted to make this heat supply a little cheaper. Propane here (until I made a new friend last week) is $20 for 20#'s. Doesnt last long. I am hoping 220 will be cheaper and maybe a little safer since there is no flame and I would like to do this inside my house or garage since both have the correct oulets and are detached from ea other. TIA

Heres links to the PID and SSR's
http://parts.digikey.com/1/parts/758017 ... d4840.html" onclick="window.open(this.href);return false;" rel="nofollow

http://auberins.com/index.php?main_page ... cts_id=106" onclick="window.open(this.href);return false;" rel="nofollow

and the PID manual in pdf:
http://auberins.com/images/Manual/SYL-2 ... %201.6.pdf" onclick="window.open(this.href);return false;" rel="nofollow

I also have drilled holes in both sides of the box and mounted a 110v computer fan to help cool the SSR's.

[rad14701]

Aren't you over-complicating a simple controller by using two SSR's and a PID...??? Are you planning on adding sensors, or what is the purpose behind the elaborate controller...???

One PSR-25 and a potentiometer will achieve the same results... If this is your first controller build I'd suggest backing down on the complexity... Seems like I'm saying it more and more often recently that the KISS concept works well in this hobby... Aside from wow factor all the added bells and whistles do little other than bump up costs and complexity - and perhaps causing the still tender to become unattentive...

[freespirited]

Last I checked a 220v pentiometer and psr-25 was expensive. Got any links to cheap stuff? I have built this for about $60. Also last I checked you guys stated these couldnt be used to regulate heat??? I have the thermo couple, has someone found a way to make this automatic? I guess they used controllers on the gate valves etc? And I do remember you saying something about only using 1 ssr but how would you do that? Would you only interupt 1 hot?

[rad14701]

I don't know of anyone using two SSR's for a controller... One works just fine because you are still regulating the whole circuit...

Just remember, you want to control the amount of power, not temperature... That's why most PID controllers are overkill... I'm not saying it can't be done...

A 2W 500K Ohm potentiometer is only about $8 USD... But you have to have the right SSR... The PSR-25 works fine with just a pot...

[MuleKicker]

Hate to burst your bubble FS, but that pid will not work. YOu need a pid with a manual control. Not only that, but a fast cycling manual control, on a variable time base. (burstfire). Search "watlow sd" you need a P/N :
SD3C-HCAA-AARG. It needs to be programmed accordingly. You can find them on ebay for under 100 bucks. Whatcha got here wont work.

[harmca]

Found this on the net just don't kown what the blue part is resistor or Capacitor.

Anyone?

[rad14701]

Found this on the net just don't kown what the blue part is resistor or Capacitor.

Anyone?

You would need to refer to the documentation to be sure but I'm guessing that it's a capacitor but it could also be a trimming resistor... The documentation should provide a definitive answer...

EDIT: After looking at the documentation it appears that this unit requires a 200K Ohm potentiometer so that may be a parallel resistor that trims the circuit to be compatible with a 250K Ohm potentiometer...

[Swede]

I'm afraid that Mulekicker is mistaken, that Auber PID will infact do on off control, also known as manual control, providing that model is capable of it. You'll have to check the part # on the PID and compare it to the part # that manual refers to. The manual you listed does give instructions on how to set the PID to manual control.

I built a PID based controller for my still, and it's got 2 pid's, 2 ssr's, a PWM variable control (cause my cheap 10$ ebay PID didnt do manual mode) and it's quite nice. Overkill for sure, but it works, and what you have will work too. I put the pid's in to give me versatility, for mashing temp control, still temp monitoring, and soon, dephleg water control via the second PID.

If all you want to do is turn it up and down, then you can make a controller that will do that nicely with what you have, as an added bonus, it's got a built in controller.

[MuleKicker]

It may do manual control, but I bet the time base is really big, meaning cycle times are too slow.

[Swede]

It may do manual control, but I bet the time base is really big, meaning cycle times are too slow.

Why would that matter...

A heat source cycling on a 1 sec basis is going to be able to compensate for a boiler charge of 13-15+ gallons, and not show any appeciable change in output, due to the thermal mass, that's why mine works, thermal mass. Check it out....

[freespirited]

Ive read the other posts as to what I needed for a PID. I know this one will work. It has manual function. And the burst was something like 6 or 60 times per second. Something like that,I forget which one. Either way I believe would be plenty.

Swede shoot me a PM when you get that 2nd PID running. I am curious as how to get this thing to run itself, which is why I bought a PID now instead of buying a pot then switching later. I seen a setup by a respected member (forget who) but it never really went into detail.

Rad I still dont understand using 1 SSR? Would it be wired to have one constant hot and one cycled? Or since the SSR are rated to handle the volts and amps are they just using one with both legs hooked to it? If this is the case for the $10 I would rather have one on each leg to prolong life and reduce heat if possible. Thanks.

[freespirited]

Unless I am missing something wiring is pretty basic. This is what I have:

[Dnderhead]

as i see it you still have the same amps going threw them...to have the relays doubled in amps they can carry, you whould need them in parallel..

[Swede]

That'll work fine. You actually only need to switch one leg of the 220, that's how I did mine. The only thing is to remember to unplug the line in after a run if you do it like that, cause one side is still live. I saved my other ssr for a second element if I ever decide to put one on

I assume that PID has a SSR output on it? Otherwise you might need a small power supply to supply the voltage for the SSR control.

[freespirited]

Come to think of it. That was the other reason I bought two SSR's so that I didnt have a live wire when it was powered down( I bought this last year) And yes the PID has a 8v DC out for SSR's and the SSR's have a 3-32v range on them.

Dndr isnt an item that pulls 19A on 220v only pulling 10A give or take on ea 110v leg? Sorry if this is incorrect, I have some electric skills but am definetly not an electrician.

From reading in here you guys always recommended doubling the load capacity of the parts. So taking that in consideration and the fact I didnt want a live wire when it was powered down (just an extra safety). I may have messed up in the process, because ea of these is 40a and the element I have is only pulling 18-19a But then again, I believe I took into consideration this was going in a closed box so I wanted the SSR to run cooler without overheating. I guess I just went for two. So should I run like this? or should I run with only one leg interupted? Or should I run both legs on the same SSR? Thanks.

[Swede]

Put them both on, it wont really matter either way, but like you said, there will be no live line to worry about.

[beowoulfe]

I surely hope there will be a working schematic and parts list when you get it going. This sounds just like what I need.

[freespirited]

BW I will try to do it in the next couple days. I also have an extra 8"x8"x8" junction box if you are interested, The sale was for two. Shoot me a PM. After doing a run and using 10# of propane. I figured this would pay itself off quite quickly being that here electricity is about .09 a Kwh. That puts this at $2 or so a run as opposed to the $10 in LP. I can also do it inside Thanks everyone for the help.

[Caveguy]

Calculating the current is easy: Wattage/voltage.

So if your element is 4500W and your voltage is 220V > 4500/220 = 20,45A.
If you use half the voltage, the current will double > 4500/110 = 40,90A.

Using 2 SSR's like this will have no effect on the current, unless you use them in parallel, like Dnder said.

[freespirited]

If I am following you, you are stating that 220v is >20A if I add the relay to each leg this will somehow double the load, as it would running the same element on 110v? How would adding an SSR have any effect on the amp rating? It is still powering the unit at 220v as the PID would switch them on/off simultaneously not reduce power. Even if what you are stating is correct since this is a switched power not a variable power I would only be effecting the heat the SSR's build in the opposite way I was trying to do. And the SSR's would still be rated well over the amperage.

[Swede]

Calculating the current is easy: Wattage/voltage.

So if your element is 4500W and your voltage is 220V > 4500/220 = 20,45A.
If you use half the voltage, the current will double > 4500/110 = 40,90A.

Using 2 SSR's like this will have no effect on the current, unless you use them in parallel, like Dnder said.

Breaking both legs by putting the ssr's on both lines will not reduce the voltage to 110, nor will using a 50% cycle time,

[freespirited]

Also Swede:

If you break the leg from one side only wouldnt you be running the element at 110v making a steady 1125 watts or so on the element when the pid switches off? Does this not matter? I would think 1125 watts constant would make for hard temp regulation since it should be able to maintain steady heat at lower than 1125 watts. I have seen others post they can run steady at 1/3 of this with good insulation? Whats your opinions?

[Prairiepiss]

You have the same current draw on both legs? If the element is pulling 10 amps both legs of the 240 will be carrying 10 amps. Because the element needs the 2 legs to work. Basically it goes I one and out the other. Except its AC so it actually goes back and forth.

By the way when you are using the 2 hot legs to make 240. They are no longer 110 v legs they become 240 v legs. They are not supplying 110 in this configuration. So why call them 110 v legs?

The second ssr is just another part that is not needed and another potential failure point. Waist of money and of a good part. How many circuits do you know of that actually shut both legs off? Do you plan to keep it plugged in all the time? If not then why worry about it? If you are that's not very smart? But by all means have at it. It's not my money your wasting. So why should I care?

Posted while freespitited was. And free the element will not work with on wire going to it. It needs 2. And the 2 hooked up to it make 240 v not 110 v. So if you break one leg you just shut it off.

[freespirited]

I gotcha thanks for giving it to me straight PP and Swede. To run the 110v you need the neutral to complete the circuit. Looks like I got the parts to build most of another one. Another PID and I have a spare. LOL Oh well I would rather over think it then under think it. Thanks for the help guys.