Water sensor/power shutoff *urgent help needed*

Discussion in 'The Projects Forum' started by kyroguy, Feb 18, 2011.

  1. erich_7719

    Active Member

    Oct 14, 2009
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    Those were were the circuit board. basically for easy hook up/possible replacement of wires/sensors IF ever needed. You don't have to use them.
     
  2. kyroguy

    Thread Starter Member

    May 12, 2010
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    Makes perfect sense. I have always done it the hard way, just solder and pray you never need a replacement. This should work out much better!

    Still waiting on the sensor to arrive then I start putting it all together.
     
  3. erich_7719

    Active Member

    Oct 14, 2009
    92
    7
    Hope to see no problems when the sensor arrives, I will be watching for your post (good or bad).
     
  4. kyroguy

    Thread Starter Member

    May 12, 2010
    77
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    All parts have arrived! Methodically building now. I am really slow when bread boarding. Stand by for SOS call. :)

    I have to say, so far I am NOT impressed with mouser. I'm less than halfway through and already two separate part numbers were not packed in the right quantity. I doubled up on most of the small components to make it easier on myself if I messed up and good thing I did. I will be contacting them for sure and probably not ordering again. Anyone else have this problem with their order accuracy?
     
    Last edited: Mar 14, 2011
  5. kyroguy

    Thread Starter Member

    May 12, 2010
    77
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    Ok, time for the dumb questions.

    1. Is this:
    Mouser #: 594-H222K33X7RL63J5R Mfr. #: H222K33X7RL63J5R Desc.: Ceramic Disc Capacitors .2LS 2200PF 500V 10%

    the 22uf capacitor?

    2. If you revisit the parts list page you made (https://www.mouser.com/ProjectManager/ProjectDetail.aspx?AccessID=88fd98825d) did we forget the 560 resistor? It appears one is needed to hook the relay back up to the 12v source. I can just hit radio shack if need be.

    3. Where does the sensor go? I have been looking at this schematic for weeks and never noticed that I have no idea where the most important component goes!

    4. I seem to have several extra parts. Are these for the 12v regulator?

    I think that does it for now. I pretty much have it all bread boarded except for the last relay hookups and the push button switches. I think I will wait to wire the switches until I actually solder everything together. I can just touch wires together to test it in the mean time. I can assure you, you would laugh if you saw me working on this.
     
  6. erich_7719

    Active Member

    Oct 14, 2009
    92
    7
    Thats acualy 2.2uF but will work all the same for the porpuse it is being used for.

    After re-looking at the data sheet for the SSR, the 560 resistor was not needed.

    I have attached a clean schematic in PDF form that will show pin numbers for the AND chip. In the schematic I have the push button in pin 1 and the sensor on pin 2.

    If you're refering to the MC7812CTG and the .1uF and .33uF Caps than yes, if not than please list the parts you are in referance to.

    Remember 2 things, 1. when you make the final board one of the .1uF Caps are for decoupling the power supply to the chip; 2. ground all chip inputs that are not in use.
     
  7. kyroguy

    Thread Starter Member

    May 12, 2010
    77
    0
    I will do some more messing with this in the morning in light of this info. I am sure you will hear from me again soon. Thanks.
     
  8. SgtWookie

    Expert

    Jul 17, 2007
    22,194
    1,764
    Wait a minute - 2,200pF is 2.2nF, which is 0.0022uF, or 1/1000 of 2.2uF.
    Radio Shack doesn't have much in the way of caps around the desired size.
     
  9. erich_7719

    Active Member

    Oct 14, 2009
    92
    7


    I was tired when I replied to the inquiry; you are right with the conversion.

    on the other hand Radioshack does carry a 2 pack of .1uF Caps. and since we are just de-bouncing a push button input that gets (for lack of better terms) latched high. Would you think that a .1uF would work for this purpose?
     
  10. SgtWookie

    Expert

    Jul 17, 2007
    22,194
    1,764
    Perhaps. Increase the resistor value to compensate.
     
  11. erich_7719

    Active Member

    Oct 14, 2009
    92
    7
    So in light of the discovery that I mixed up the conversion, here what can be done.

    Radioshack sells these, you'll need either the .1uF Cap #272-1069 or the .22uF Cap #272-1070 and a 100K resistor.

    If you move R1 and LED1 to between D1 and D2, and R4 (100K resistor) where R1 was, and change C2 to the .22uf instead of 22uF; will give the same Cap charge for de-bouncing. If you have to get the .1uF it will work as well but to get the same effect you would need 150K which can be made with 3 100K resistors.

    [​IMG]
     
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  12. kyroguy

    Thread Starter Member

    May 12, 2010
    77
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    Ok, you're going over my head now.

    I tested my intended power supply. It is pushing out over 16v (despite the lower rating on the label). Will the regulation circuit compensate for that?
     
  13. erich_7719

    Active Member

    Oct 14, 2009
    92
    7
    yes. the regulator, will handle a input up to 35V. the 16V you are seeing is because the PS is a unregulated 12V supply.

    Which part? This way I can try to help more.

    edt. Grammer
     
    Last edited: Mar 15, 2011
  14. kyroguy

    Thread Starter Member

    May 12, 2010
    77
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    I didn't realize there was a 6th page to the thread. I had bookmarked the 5th one. I didn't see where the capacitor discussion was going but your diagram made it clear. Disregard this bout of confusion...and prepare for the next one! ;-)
     
  15. kyroguy

    Thread Starter Member

    May 12, 2010
    77
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    Two questions.

    1. Are there are two grounds here, or just one? In other words, is every ground the same or should I separate the "voltage regulator" ground from the rest of the circuit ground? Hopefully that makes sense.

    2. I am reviewing the schematic you posted (pdf version) and am unsure of the power regulator portion. Is the "power input" where the unregulated supply enters? If so, there are "+12v" and "gnd" at both ends. Where does the regulated power come out? Also, what is "IC1P" and "IC2"?

    I tied the inputs together and put them all to ground on the AND gate chip. I'm all tuckered out for the night. Thanks for the help, guys!
     
  16. erich_7719

    Active Member

    Oct 14, 2009
    92
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    one ground, they are all tied together.

    Yes, IE terminal block "power input".

    If your refering to the 12V above the circles with the + sign in them, than that represents the regulated 12V.

    So for hook up put the unregulated 12V on X4-1 and the ground of the wall wart to X4-2.

    For eagle the IC1P represents the power pins for IC1 (the and chip, 4081N).

    IC2 is the MC7812CTG (<--Data Sheet). If you lay the regulator on the table heat sink down the pins are numbered from left to right. #1 INPUT #2 GROUND #3 OUTPUT.

    I can update the schematic to tie the supplies together where needed if you need, just let me know.

    Hopefully this answers your questions, If not I'll be up all night.
     
    Last edited: Mar 16, 2011
  17. erich_7719

    Active Member

    Oct 14, 2009
    92
    7
    I did some number crunching and noted that we were in the danger zone for the AND chip. the total current that was needing to be supplied by the chip was 10.3mA and according to the data sheet the maximum is +/- 10mA, So I moved LED1 and R1 to be in parallel with the SSR, which lowers it to 1.4mA needed from the chip. Pages 3 and 4 show the limits for the chip.

    I also redrew the schematic to help answer some questions, uploaded in PNG and PDF form.

    I put this note on the schematic but I will state it here as well, The blue boxes represent terminal blocks.
     
    Last edited: Mar 16, 2011
    kyroguy likes this.
  18. kyroguy

    Thread Starter Member

    May 12, 2010
    77
    0
    I must have a loose connection somewhere because it isn't working on the breadboard like it should. With me holding connections and my wife holding the board down there is high likelihood that a connection came loose. I think I will just solder it all on the board tomorrow morning. I suck at breadboarding. Nothing got hot, at least that is a better start than my last project...

    Question. Do the "load" contacts on the relay have to be hooked up to something for it to open and close right? I was just using an ohm meter to check for continuity to determine if it would have let power flow or not. Maybe that was my problem.

    In any event, I picked up the project PCB and the box to contain it all tonight. I will cut and drill the box tomorrow to make it all fit nicely inside. I want to make it look nice on the outside even though inside it will be a complete cluster**** of wires.
     
  19. erich_7719

    Active Member

    Oct 14, 2009
    92
    7
    For the SSR the load has to be AC to see any thing. so you ohm meter wont see any thing.

    If you haven't taken it apart yet could you take a pic of your bread board?
     
  20. kyroguy

    Thread Starter Member

    May 12, 2010
    77
    0
    Well that may explain why I wasn't getting anything with the ohm meter. The LED's were acting a little strange too so I still think I had a loose connection.

    Here is a pic of the board. Not very clean so I don't think it will help you.
    [​IMG]

    I will wait for your suggestions before proceeding.
     
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