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Remote controlled starting grid lights circuit help

Discussion in 'LEDs and Optoelectronics' started by Gitza, Aug 23, 2016.

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  1. Gitza

    Gitza

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    Jun 28, 2016
    I have been tasked in making a replica of the Le Mans starting lights. It will consist of four 240v bulbs behind lenses in a single row of red, red, red, green. The client would like them to be all on then with a remote button press, it sequence 1, 1+2, 1+2+3, 4 like the start of a race.

    So far what I have come up with is potentially using a relay board to the 4 bulbs. An Arduino to that board to sequence the lights with a button to activate it. A 2Ch RF remote with button 1 for turning everything on or off and button 2 to start the sequence.

    Problems I've come across so far are:

    The receiver is 12V but the Arduino is 5v (know they can take 12v on the VCC but they get hot and this might be in direct sun, all day, in a box and it CANNOT break down) So I thought a DC-DC buck converter would fix that?

    The receiver can be latch type, momentary or toggle but do I not need toggle for the power on/off and momentary to the Arduino to activate the sequence. Also the signal would be 12V and it needs to be 5V for an Arduino?


    I would really appreciate some ideas or suggestions because I just do not know the best way to go about this!

    Many thanks in advance.
     
  2. AnalogKid

    AnalogKid

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    Jun 10, 2015
    If I understand this correctly, it is a 5 step sequence that sits in step 1 for an unknown time, then moves through steps 2-5 at a fixed rate when triggered, ending by sitting in step 5 for an unknown time:

    Button #1 turns on everything, system starts at step #1:
    1. 1+2+3+4
    System sits in step #1 until button #2 is pressed. It then steps through everything automatically at a fixed rate:
    2. 1
    3. 1+2
    4. 1+2+3
    5. 4
    System sits in step #5 until button #1 is pressed again to turn everything off.

    If that is the sequence, this can be done without an Arduino or any other programming stuff with a couple of CMOS chips and your relay board or some solid state relays. Is building a small circuit an option?

    All 12 V parts eliminates power issues.
    CD4017 Johnson counter as stepper.
    ULN2803 as output relay drivers
    Set both receiver channels to toggle. One toggle controls power to the controller circuit, and one toggle enables the stepper (the stepper can use either phase of the toggle).

    ak
     
  3. Gitza

    Gitza

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    Jun 28, 2016
    Many thanks for your reply. I'm sorry if my ramblings were not too clear!

    That is what I need it to do apart from after step #5 it would be better to revert to step #1 after a set time rather than turn off. The idea of the button for on/off was purely to make turning the whole thing on/off easier and will probably only be used once in the morning and evening over the 3 day event so perhaps a simple physical switch on the unit would do.

    Building a small circuit would be absolutely great! I run a lighting company and having the ability to use this for future projects would be invaluable. Problem is that I'm not great with knowing exactly what components I need or how they go together so if you would be able to help me I would be in your debt!

    I had this Rx and Tx in mind, will this be ok?

    http://www.ebay.co.uk/itm/2-Channel...hash=item27df2b0335:m:m3EYYzi-SoSie6Erz1cfz9Q

    I had a look for those chips and came up with:

    http://uk.rs-online.com/web/p/counters-shift-registers/7320691/
    http://uk.rs-online.com/web/p/darlington-transistors/6466305/

    Do those looks right?

    Thanks again,
    Ollie.
     
  4. AnalogKid

    AnalogKid

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    Jun 10, 2015
    Those are the right parts. Turning everything on and off with a physical switch means the receiver is not on 24/7, probably a good thing. AND, it makes the controls easier:

    Power on - reset to all lights on. Wait.
    Button #1 - run through the sequence, stop with just light #4 (green) on. Wait. (see note)
    Button #2 - reset to all lights on. Wait.

    Note - At the end of the sequence, the system can park with any light pattern on or all lights off. It does not have to be the last light lit.

    ak
     
    Last edited: Aug 24, 2016
  5. AnalogKid

    AnalogKid

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    690
    Jun 10, 2015
    Photo / datasheet / website link ?

    ak
     
  6. Gitza

    Gitza

    12
    0
    Jun 28, 2016
    Indeed, that sounds much better/easier! I like the idea of it staying on green until button press to revert to all on.

    This is the board I was looking at;

    http://www.hobbytronics.co.uk/8-channel-relay-12v-t?keyword=relay

    I was going to order the chips and noticed they did not have the stock so tried another place but they only had an alternative, is this still correct?

    http://www.mouser.co.uk/Search/ProductDetail.aspx?qs=zqbRmZ%2bfZD8M77SqrzUfYg==

    http://www.mouser.co.uk/ProductDeta...=/ha2pyFaduhlhkzCEtStsIDFnTOfU6VQiTgautC3Ja8=

    Thanks again for all your help :)
     
  7. AnalogKid

    AnalogKid

    2,425
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    Jun 10, 2015
    Depends. What is your skill set for assembling a circuit on perf board or a proto socket board? The 2803 part is in a D package. That is one of the larger surface mount packages, and can be hand soldered without great difficulty. However, it won't work with a proto board or standard perf board because it does not have long pins. What is your pland for assembling the circuit and packaging it against the elements?

    ak
     
  8. AnalogKid

    AnalogKid

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    Jun 10, 2015
    Full disclosure, almost everything on this schematic can be replaced by an 8-pin PIC. But enough about typing.

    Here is a first pass at a light tree timing circuit. U1 is a counter that steps through the timing pattern. U2C is the timing oscillator, current set to 2 Hz (-0.5 seconds per stage). U2A and B are the control flipflop that takes commands from the receiver module. U2D is a spare section. C2 forces the circuit to power up in the RESET state, all lights on and waiting.

    Q1 and U3 are the output stage, and are not finished pending more discussion about the relays that switch the lights on and off. Depending on the relay board, they might be replaced by a group of about 11 small signal diodes. A lot of schematic clutter, but cheap and reliable.

    ak
    Light-Tree-1-c.gif
     

    Attached Files:

    Last edited: Aug 25, 2016
    Arouse1973 likes this.
  9. Gitza

    Gitza

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    Jun 28, 2016
    I don't have *loads* of experience with making circuit boards, however I am highly competent with soldering. What you recommend I use to make the circuit? As for the circuit board housing, I can make an enclosure for anything.

    I have attempted to understand the diagram you created for me and I think I kind of get some of it. What else did you need to know about the relays, were you able to have a look at the board I linked?

    I have found a better supplier and have got these so far. What sort of wattage will I need on the resistors?

    http://uk.farnell.com/panasonic-ele...eb1j100s/cap-alu-elec-10uf-63v-rad/dp/2079130
    http://uk.farnell.com/nxp/2n7002-215/mosfet-n-ch-60v-0-3a-sot23/dp/1510761
    http://uk.farnell.com/texas-instruments/cd4093be/ic-4000-cmos-4093-dip14-18v/dp/1106117
    http://uk.farnell.com/stmicroelectronics/uln2803a/darlington-array-8npn-2803-dip18/dp/1094428
    http://uk.farnell.com/texas-instruments/cd4017be/ic-4000-cmos-4017-dip16-18v/dp/1106100

    I really can't thank you enough for your assistance with this. I only have a couple of weeks to get this made now and I need to order parts soon but if you had PayPal address I would love to buy you a couple of cold ones in thanks :)
     
  10. AnalogKid

    AnalogKid

    2,425
    690
    Jun 10, 2015
    If you can figure out how to smuggle Samuel Smith's Best Bitter...
     
  11. AnalogKid

    AnalogKid

    2,425
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    Jun 10, 2015
    It all comes down to the relay board. Roaming around on ebay it looks like there are two basic kinds, one with optocouplers on each control input, and one with a simple transistor driver on each input. The problem is that there is no documentation to get a good solid feel about hot to drive each board type. While you don't need the optocoupler isolation in this application, it looks like the safer way to go because it says it can be configured for either pull up or pull down operation. Something like this:

    http://www.ebay.com/itm/12V-4-Chann...029172?hash=item25c04c80f4:g:RQAAAOSwMsVXjHF~

    Here is a modified schematic that *should* work. All resistors can be 5% tolerance, 1/4 watt. We don't know if the relay board inputs need current limiting resistors. You can ask the vendor for advice; even better, a schematic. I recommend all thru-hole parts (no surface mount) and perf board/solder. A protoboard is much faster, but less reliable away from a workbench. Another note is that I show connectors for all Inputs and outputs, but you can solder I/O wiring directly tot he board. Connectors are pretty much mandatory in a production environment, but not so much for a one-off.

    ak
    Light-Tree-2-c.gif
     

    Attached Files:

    Last edited: Aug 26, 2016
  12. Gitza

    Gitza

    12
    0
    Jun 28, 2016
    So have ordered up the parts and they will come tomorrow so hopefully I will have some time to try it all out.

    I got all thru hole stuff and a board to solder it all too. I got screw terminals for the relay board and receiver for a bit of neatness.

    Is there anything I need to know when putting together or any setup required once its complete?

    Once again, thank you so much for all your assistance..... although I'm not quite sure how to smuggle the bitter in yet! :p
     
  13. AnalogKid

    AnalogKid

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    Jun 10, 2015
    Capacitors C4, C5 are decoupling capacitors for the three ICs. They should be placed as close as possible to the power pins of each chip. Also, note that the schematic does not show these power pins. That's because most schematic software does not. Power and ground connections are assumed to be connected correctly, and leaving them out of the drawing removes a lot of clutter.

    C3 is bulk filtering for power coming into the board, and should be placed close to the incoming power connector or wires.

    Did you contact the relay board vendor to see it it requires current limiting resistors (R? 220ohm in the drawing)?

    ak
     
  14. Gitza

    Gitza

    12
    0
    Jun 28, 2016
    I have asked the vendor but not heard back yet. I have resistors just in case too.

    I think I may have misunderstood the schematic however. Apologies for being a noob but I think I need some help understanding how this circuit goes together.

    The section with the three caps, is that needed for each 4093 chip? The VCC in on there is the 12v in but what are the P1's two connections from? What does the #11 go to?

    I assume the numbers next to the chips are the leg numbers, yea?

    Cheers man.
     
  15. Gitza

    Gitza

    12
    0
    Jun 28, 2016
    I have the relay board now but I still didn't hear back yet regarding the input resistance.

    It has either low level or high level triggers and I looked that up and I think I need it set to high level trigger so when the input voltage goes up it is triggered?

    Thanks mate.
     
  16. AnalogKid

    AnalogKid

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    Jun 10, 2015
    Nope. The outputs of the 2804 go LOW when active. Did any documentation come with the board?
     
  17. Gitza

    Gitza

    12
    0
    Jun 28, 2016
    Afraid no documentation, however I did order two of everything in case anything was to go wrong!

    Ok I will set the triggers to low.

    Sorry to be a pain but would you be able to help me regarding my post #14. Only this needs to be built by Thursday and the panic is beginning to set in!

    Thanks again mate,
    Ollie.
     
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