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interlocking switch

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by Adrian116, Jul 30, 2008.

  1. Torben

    Torben Well-Known Member

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    Hi Mike!

    Yeah, I got that there would be one remote in each room. What I'm trying to determine is whether it's expected to reach only from a portable unit the customer can activate (say, from the bed or something) to light up the LEDs on a door unit, or whether the idea is that there will be some central control room which must receive signals from all the rooms.

    If it's the first option, then Adrian's diagram might work, since no remote needs to be able to send a signal further than that room's door. If it's the second option, then I agree with you, and some other communication method should be looked at. I was thinking about Wifi or Zigbee modules, perhaps.

    A wired approach would be easiest, I agree. But if the hotel owner doesn't want to lay wire for it, the only ways I can see to do that would be to piggyback on the phone or AC lines. Those ideas open their own cans of worms. :)


    Torben
     
  2. Mikebits

    Mikebits Well-Known Member

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    That seems to defeat the purpose of going wireless as each receiver will still need to have wires ran to it. Why not just use a wired interface and run wire under carpet or some such. To reduce amount of wires, a 2 wire multi addressable serial link could be used.

    Just a thought :)
     
  3. Adrian116

    Adrian116 New Member

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    Actually this kind of service should be done with wire and is more reliable. I think the haven't consider about that when they construct the building. Also each time the battery is used up , they need to recharge them. But there are may be some hundred rooms. Also , i don't think this idea work properly.

    I also asked my boss why don't they used wire. He told me that it is hard to provide voltage source for that device......
     
  4. dave

    Dave New Member

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  5. Torben

    Torben Well-Known Member

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    I don't know. Why don't you use the original remote control? I'm guessing it's so that people don't steal them. Then again, you could always keep extras in stock and put a "remote control deposit" on the bill. For instance, if the remotes cost $10 each, then add $10 to the room bill, which will be returned to the customers when they return the remote control to the desk when they check out.

    Ah, OK then! That simplifies things quite a bit. In that case your diagram might work.

    To what will the control unit be fixed? The receiver will be fixed to the door or to the wall near the door, right?


    Torben
     
  6. Torben

    Torben Well-Known Member

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    I agree--if the devices are fixed, simply run power lines to each device. The savings against using batteries over time should outweigh the cost of running the wires.

    If each control unit only ever needs to communicate with its own display unit at the door, then wouldn't just two wires for the commands be enough, and not even need to be addressable? Two bits is enough to represent four states, and we only need to represent three states.


    Torben
     
  7. Mikebits

    Mikebits Well-Known Member

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    Ok, now I got ya! :) I kept thinking one central command center type thing. Yes this simplifies thing as Torben said. Now were rolling. But now I am back to, if the service personel have to go look for lights being on, why not use the little clean my room cards on the doorknob...

    Sorry, not trying to be a pain :(

    It would be easier if we could be in a meeting room to hash all this out..Oh well :)
     
    Last edited: Aug 5, 2008
  8. Adrian116

    Adrian116 New Member

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    I think the control unit may be fixed near the bed. the reciever will be fixed to the outside door.
     
  9. Mikebits

    Mikebits Well-Known Member

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    So, hey yo Adriaan...

    Is this what your kinda envisioning? See pics.
     

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  10. Torben

    Torben Well-Known Member

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    From what I understand, that's what Adrian wants, except without the yellow LED. I think the "Clear" state is just to ensure that neither the green nor the red LEDs are lit.


    Torben
     
  11. Mikebits

    Mikebits Well-Known Member

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    It seems as though we may now be getting on the same page which should allow things to go smoother :) Now we need the RX interface to figure out how to turn on the outside LEDS ...
     
  12. Torben

    Torben Well-Known Member

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    Yup.

    If anybody is interested I put a short video of my three-relay monstrosity up on Youtube ( http://www.youtube.com/watch?v=w3E-c3mAOnc ). Caveats are as in my earlier posting on it. Again, I still don't recommend it as a solution, I just wanted to see if I could solve the problem using no timers or µcs. This does the trick but can still be fooled by quick switching. However, the errors can all be compensated for at the receiving (display) end if necessary.

    I've also attached a map of what LED means what.


    Torben
     

    Attached Files:

  13. Mikebits

    Mikebits Well-Known Member

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    Wow, I thought I was cool with my 3D model. But video and everything... Gotta love that:) From the way we now understand the setup, I do not see false triggers as being an issue as there is no real alarm sent. It is only the final state that matters. That is what I am thinking...
    Oh yeah, quit bitting your nails...lol :)
     
    Last edited: Aug 6, 2008
  14. Torben

    Torben Well-Known Member

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    Well, as it looks the whole point for that circuit is moot anyway. :)

    Biting my nails?


    Torben
     
  15. Mikebits

    Mikebits Well-Known Member

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    Sorry, my humor sucks, All we could see was your hands, so I tried to make a funny :(
     
  16. Torben

    Torben Well-Known Member

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    :)


    Torben
     
  17. Adrian116

    Adrian116 New Member

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    yes, somehow like that, nice picture:D
     
  18. Mikebits

    Mikebits Well-Known Member

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    I am not so sure the picture is nice. The pastel purple walls just seem to clash with the leopard print on the bedspread :)

    My bad humor again :)
     
  19. Adrian116

    Adrian116 New Member

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    Hey, nice testing~:)
    Have you posted that circuit before?

    what is the right two LEDs for?
     
  20. Torben

    Torben Well-Known Member

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    That circuit is the one in the schematic I posted earlier, yes, just with a couple of modifications to make it obvious what it's doing in testing.

    Here is a better explanation of the LEDs (as labelled in the photograph, from left to right):

    "Do not disturb pulse indicator": This LED wouldn't be in the final circuit; it's just there to flash when the relay contacts for the Do Not Disturb signal are briefly closed.

    "Do not disturb": Indicates that the switch is in the Do Not Disturb position.

    "Please clean": Indicates that the switch is in the Please Clan position.

    "Please clean pulse indicator": This LED wouldn't be in the final circuit; it's just there to flash when the relay contacts for the Please Clean signal are briefly closed.

    "Clean pulse indicator": This also wouldn't be in the final circuit; it's just there to flash when the relay contacts for the Clear are briefly closed.


    Torben
     

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