1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

need a switched output for a relay...help

Discussion in 'DIRECTV General Discussion' started by fl panthers, Dec 15, 2011.

  1. fl panthers

    fl panthers Legend

    159
    0
    Sep 18, 2007
    Hey all, I just built a custom entertainment built in for my tv,projector screen. All of my equiptment is in a closed cabinet that vents out of a speaker grill above it.

    Like a sauna. My hr20 was running very warm 131f. I added 3 92mm fans to push the hot air out the top and it seems to work well.hr temp now 120f. I want to turn them off and on with a relay if I can find a output on a peice of equiptment that throws voltage enough to throw a relay when turned on and off. Any suggestions?

    I am using a 12v transformer for power just need a trigger. Everything is controlled with a harmony 890 so a toggle is to basic.
     
  2. dsw2112

    dsw2112 Always Searching

    1,938
    0
    Jun 12, 2009
    Why not use a thermostat? What's the temp of the HR when everything is "off"?
     
  3. fl panthers

    fl panthers Legend

    159
    0
    Sep 18, 2007
    117f when audio reciever,power supply are off. cabinet is very warm with all on but the hr is the lowest so cabinet is warmer than the hr shows.thermostat is good idea. I found one by coolerguys thats progammable for a little over 50 plus shipping. I own relays already so its free if I can find a trigger.
     
  4. davring

    davring Hall Of Fame

    6,417
    1
    Jan 13, 2007
    Use an attic fan thermostat, they have a higher operating temperature threshold and are only about $15.00.
     
  5. dsw2112

    dsw2112 Always Searching

    1,938
    0
    Jun 12, 2009
    It really depends on the types of relays you have. What trigger voltages can you use?
     
  6. fl panthers

    fl panthers Legend

    159
    0
    Sep 18, 2007
    home depot I would assume? I will check that out.
     
  7. fl panthers

    fl panthers Legend

    159
    0
    Sep 18, 2007
    Standard relay like you use in a car. Not sure how much voltage I would need for a trigger. the 12v would be the power side just need a trigger that is an output on a peice of equiptment I was hoping. Like my projector has a 12v trigger but if I am watching the tv the projector is off.
     
  8. dsw2112

    dsw2112 Always Searching

    1,938
    0
    Jun 12, 2009
    If it's automotive then it's likely to be a 12VDC coil (trigger.) Personally I think the relay is just the wrong route (and will require extra wiring.) What if the cabinet temp rises when everything is "off"? I would really look at a thermostat as the solution; it's really the correct solution for your problem.
     
  9. fl panthers

    fl panthers Legend

    159
    0
    Sep 18, 2007
    I see your point.I just figured if everything is off except the hr the temp in the cabinet is room temp or very close. If anything is on other than the hr the temp goes up instantly so if it turned on with the audio reciever it would run while the heat source is in use. Im going to look at the attic thermostats like was suggested above but if they are 25 and the one designed to do this by coolerguys http://www.coolerguys.com/840556093701.html is 50ish.I would just buy it instead of rigging it.
     
  10. fl panthers

    fl panthers Legend

    159
    0
    Sep 18, 2007
    Would a old a/c thermostat work?
     
  11. Davenlr

    Davenlr Geek til I die

    9,139
    28
    Sep 16, 2006
    To bad they didnt incorporate a thermostat controller like computers use, that ramp up the fan(s) speeds depending on the internal temperature. Then you wouldnt have the noise of the fans turning on and off at full speed.
     
  12. fl panthers

    fl panthers Legend

    159
    0
    Sep 18, 2007
    That would be nice but the fans are almost undetectable since they are inside a closed cabinet.About a foot down inside thecabinet pushing air up toward vent area behind a speaker grill. You need to open the door to hear them at all anyway. muting the tv ans turning off the a/c you can only tell they are running if you put your head next to the grill.
     
  13. dsw2112

    dsw2112 Always Searching

    1,938
    0
    Jun 12, 2009
    Is it for a motorhome? You've got 12VDC relays, and it sounds like your fans are running from a 12VDC source.

    Are you against letting them run constantly? With a transformer in the mix you've already got standby loss :lol:
     
  14. fl panthers

    fl panthers Legend

    159
    0
    Sep 18, 2007
    No from a regular home.
    Not against anything just life expectancy of the fans is greatly reduced if they run constant.dead in 5.7 yrs instead of 20 lol
    Standby loss...:) I have about 9 transformers for all the switchers,adaptors,wii,2 hard drives,harmony cradle,harmony repeater. what 1 more?
     
  15. davring

    davring Hall Of Fame

    6,417
    1
    Jan 13, 2007
    Attic thermostats, like I mentioned earlier, are usually line voltage contacts. You could either swither the 110v to your transformer, or the 12v to the fans, they require no operating tranformer.
     
  16. fl panthers

    fl panthers Legend

    159
    0
    Sep 18, 2007
    This sounds the easiest. depot has one for 26 plus tax. where can I get one cheaper?
     
  17. davring

    davring Hall Of Fame

    6,417
    1
    Jan 13, 2007
    I use mine for the same exact application, IIRC I got mine at Graingers, about 15.00 bucks.


    Edit, it was about four years ago.
     
  18. fl panthers

    fl panthers Legend

    159
    0
    Sep 18, 2007
    Update... old a/c thermostat works fine with the r and y contacts as all thats used. negative side as the switch. works great just need to get temp right. thanks for everyones input.:D
     
  19. bigglebowski

    bigglebowski Legend

    225
    2
    Jul 27, 2010
    This is the first thing I thought of when I read the thread: http://www.hammfg.com/pages/s8_climate_cntrl/p421_thermostat.htm

    This is elegant since you would use in in conjunction with whatever you are using to power your fans. This way the device will keep the fans running per your set temperature as long as it takes to cool the enclosure down. Just like in projectors the fan keeps blowing to cool the lamp down well after the projector powers down. That would be better than the receiver cutting off and killing the fans since the devices are at their peak hottest temp if they were on a while. These run $30-35
     
  20. buddybailey

    buddybailey Mentor

    47
    0
    Oct 16, 2007
    What is the source of intake air?
     

Share This Page