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Wiring PID and SSR = need some help

Discussion in 'UDS Builds' started by flyweed, Aug 23, 2010.

  1. flyweed

    flyweed Smoking Fanatic

    Guys I am wiring up my PID, SSR and a plug in outlet into a hobby box, but am stuck trying to decipher these chinese instructions.

    The SSR I have is a 40 amp/250v

    it has 4 set screws..two on top and two on the bottom  the bottom two have a line that says "INPUT" and under that it says 3-32vdc.  Screw 4 has a "-" symbol and screw 3 has a "+" symbol

    Now on the top..it doesn't say INPUT, it just says 24-380VAC  and screw 1 and 2 both have a little ~ by them.

    what hooks up to where on this?

    2.  on the PID, I have a thermocouple with 3 wires..a red or positive and a black with a yellow crimp on it..and then a blue wire...I assume the thermocouple connects nevative to screw 6, positive to screw 7..but what does the blue connector on the TC connect to on the PID?  And lastly how do I connect power up to this unit, and what does my plug in that will control the blower motor connect to?

    Sorry, I have so many questions..but these directions that came with the PID, TC and SSR are useless.

    THanks for any help

  2. flyweed

    flyweed Smoking Fanatic

    here's a photo of my SSR

  3. flyweed

    flyweed Smoking Fanatic

    and here is the PID I am using.  there are 10 connections on the back. 1 and 2 say "ac/dc 85-265v 

    3 is ground, 4 and 5 say "J1 output

    6 is negative for thermocouple, 7 is positive for thermocouple, 8 is labeled "R" and ties in to 7.

    9 says SSR output - and 10 says SSR output +

  4. meateater

    meateater Legendary Pitmaster SMF Premier Member

    Charcoal and a match? Sorry I'm still cavemanning it. [​IMG]
  5. tom37

    tom37 Master of the Pit OTBS Member SMF Premier Member

    Sorry man, I don't have a clue but I am interested in folowing this thread to try and learn.
  6. justpassingthru

    justpassingthru Smoking Fanatic OTBS Member


    I might be able to help you, I just received my PID,

    My first question is why do do think it's a 250v SSR? The reason I ask is on the top of the SSR it says it's good for 24-380 volts AC, are you trying to use 220 volts AC, why not just use 110 volts?

    The SSR

    1.  The left hand screw #1 is you line in voltage to the SSR, the hot wire of the power cord connects to this terminal, but the hot wire also connects to the AC screw #1 on PID so you will need a short length of wire and a wire nut to join the three wires together.

    The #2 screw on the SSR is the hot wire to your blower.

    The #3 +(pos)screw on the SSR is connected to the +(pos) DC screw #10 on the PID

    The #4 -(neg) screw on the SSR is connected to the -(neg) DC screw #9 on the PID.

    2. First is your thermocouple a K type? If so the +(pos) connects to the  +(pos) screw on the PID and the -(neg) to the -(neg) screw on the PID, if the polarity is reversed the PID will read in the opposite direction, example: if the temp is rising the PID will be descending, if this is the case just switch the wires, the third wire could possibly be a ground for the shielded cable and my directions say to connect it to the -(neg) only if the the PID display changes erratically. 

    We're not done however,

    The neutral wire of the AC power cord is connected to the neutral wire of the blower and  a short wire to the other AC screw #2 on the PID, with a wire nut.

    Lastly the ground wire of the power cord is connected to the ground wire of the blower.

    I hope that helps,

  7. flyweed

    flyweed Smoking Fanatic

    Gene  I don't need 250v...as I am powering it up with only 120vac...however, I think this SSR is rated up to 250vac..that's all.  Thanks for all the other help

  8. flyweed

    flyweed Smoking Fanatic


    one more question. I am not wiring directly to my blower...however, I am wiring a "plug in" in which I will be able to plug my blower in to.  It has a brass nut on one side and a silver nut on the other....so which color does the Hot wire from the SSR go to??

  9. justpassingthru

    justpassingthru Smoking Fanatic OTBS Member


    If I remember rightly, the saying goes, "brass-black, silver-white, ...It's been a long time, I'm not sure on that one, but if it's reversed it should still work unless the blower has a polarity, but come to think of it, if it's reversed polarity the blower would turn in the opposite direction, if that happens then just change the connections.

    So, to answer your question, the hot wire from the SSR connects to the brass screw.

  10. flyweed

    flyweed Smoking Fanatic

    cool. Yeah, I can always reverse it..if it doesn't work right...no big deal

    Oh..here is my Thermocouple..I am not sure what "Type" it is.

    info: This PT100+ type thermocouple probe has a super wide measurement range of 0 to 400°C, an extra long 92cm flexible cable and is brand new and unused. It also benefits from an extra cable which acts exclusively as an output stabilizer.

  11. justpassingthru

    justpassingthru Smoking Fanatic OTBS Member


    That's what I was talking about with the third cable.

    Here is what my instructions say:

    There are two commonly used color codes for the K type thermocouple on the market.  US color code uses yellow and red, yellow is positive.  Imported DIN color code uses red and green (blue), red is positive.  If the connection is reversed, the temperature reading will decrease when temperature increases.

    Since you said you couldn't read the Chinese instructions it's probably an imported model, red is positive and the red terminal in your pic has a insulator on it.

    My thermocouple has red and blue terminals and the red is marked +.

  12. flyweed

    flyweed Smoking Fanatic

    ok...so I have the "red" hooked up to (7-pos) on the PID and yellow hooked up to ( 6-neg) on the PID

    So  what should I do with the blue/green wire that's currently just hangin' there?

  13. justpassingthru

    justpassingthru Smoking Fanatic OTBS Member

    Hey Dan,

    I just googled "PT100+ Thermocouple," it's listed on ebay, the description says it's a "K" type thermocouple, also the white collar on the red terminal says, "PT100+" that confirms the red is +.

    The reason we need to know what "type" of thermocouple is to program the PID to the thermocouple, mine is default to "K" maybe yours is too.

    The blue is used only if the are erratic temperature fluctuations, or in your case if the blower is constantly changing speeds, if so you connect the blue to the (6-neg) terminal.

  14. flyweed

    flyweed Smoking Fanatic

    gotcha...I'll just leave it disconnected for now then.  I am still waiting for my blower to arrive (from china)..but once I get it...I"ll hook it up and see how it works.

  15. justpassingthru

    justpassingthru Smoking Fanatic OTBS Member

    I'm curious, how big is the smoker and how many cfm is the blower?

    I have a GOSM propane smoker that I'm installing a 750 watt finned strip heater, PID controlled and I'm going to use a 12 v DC fan out of a computer, I'm worried that the fan output might be too much, ...that's why I'm interested in what you're building.

  16. ol' smokey

    ol' smokey Smoking Fanatic SMF Premier Member

    flyweed, if you are just going to power a 12 VDC computer fan you can wire it through the relay terminals on your PID. I looked it up and they are rated for 3A at 240 VAC. 

    I built two PID's, one that controls a 1200 watt electric heater. On this one I use a SSR. The other runs a 5 VDC 4 CFM fan to control the air flow (temps) in my UDS smoker. This is wired through the relay terminals of the PID. 

    Hope this helps. You can always PM me with more questions.

  17. flyweed

    flyweed Smoking Fanatic

    Joe..thanks for that info..good to know..I already have it wires up through the SSR...but I'd love to see some pics, or diagram of yours, maybe I'll change it....

    Gene, I found some small blowers exactly like the blower they use on the smallest "stoker" and sell for $60.00 on their website..I got them from a supplier in china.  It is a 5vdc blower that moves 5 CFM..it will connect to one of my 3/4" air inlets on the bottom of the barrel.  my smoker, is a standard homebuilt UDS (ugly drum) smoker...last night I seasoned the barrel with just lump charcoal and some misc wood I threw on it..started it at 7:30pm...and let the temps get up to 250..then I capped 2 vents and left the ball valve open..and it dropped down to about 228F..and stayed there..last time I checked it was midnight..then I went to bed...so I can confirm that it held a rock solid temp for at least 4 hours.

    Last edited: Aug 24, 2010
  18. justpassingthru

    justpassingthru Smoking Fanatic OTBS Member


    A PID on a UDS, that's cool, I was imagining in my mind you were building a smokehouse the size of a 20' container. LOL

    One more thing, if you have any questions to ask Ol' Smokey, please don't PM him, keep it here on the board in public so that we can all benefit from his experience, sounds like he can help us a lot and yes, I would like to see his diagrams or some pics too, how 'bout it Joe?

    Last edited: Aug 24, 2010
  19. flyweed

    flyweed Smoking Fanatic

    now that would be sweet. a 20 foot container smoker! ha ha ha...I don't think my wife would like that..I already have a 12 ft container on our property that I use for a storage magazine for display fireworks.  :)  my other hobby

  20. ol' smokey

    ol' smokey Smoking Fanatic SMF Premier Member


    Dan and Gene, 

    At your request here's a diagram of the back plane of my PID.
    1. The AC power connects to terminals 1 & 2. Polarity is not an issue.
    2. Terminals 6 & 7 are for the SSR. 6 being positive.
    3. Terminals 9 & 10 are for the TC, 9 being positive.
    4. For the fan I use terminals 4 and 5 which are normally open and labeled J1. I could have also used the J2 terminals 13 & 14.
    I chose to wire the 5 VDC to the fan motor through the relays. You could just as well wire the AC through them.

    Hope this is clear as I'm not very good at explaining things.