Shop OBEX P1 Docs P2 Docs Learn Events
Optoisolators — Parallax Forums

Optoisolators

bhendrixbhendrix Posts: 9
edited 2009-09-27 02:41 in BASIC Stamp
OK, I thought of a question, what would be the best optoisolator(DIP) to use for an input(Allen Bradly Mom. button)?, I am looking for one that the Coil can handle higher voltage or 120AC, and the controlled voltage will be the 5v from the VDD pin to the Stamp input,·Im not real concerned about any amperage right now, I know about opto relays but I want something small I can put on the board with the rest of my controller in a small package.

FYI, I am making a OCS type of controller.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
GUI programming·is nice for losers!!![noparse];)[/noparse]

·

Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2009-09-24 05:08
    You'll need to be more specific about what you need to switch. Most optocouplers use an ordinary LED on the control end and they're treated just like any other LED as far as controlling with a Stamp I/O pin. You'll need a resistor, probably on the order of 330 Ohm in series with the LED to an I/O pin and you can either ground the LED cathode or connect the LED anode to Vdd depending on whether you want the I/O pin to be high or low to turn the LED on.

    If you're controlling a low DC current, you'd use an NPN phototransistor output for the optocoupler. If you're controlling more DC current, you'd want a Darlington output transistor. If you want to control AC, you'd want an optocoupler with a triac output that you'd use to trigger a larger triac to control the load. The details depend on what voltage and current you need to control. If it's anything like an Amp or more at 120VAC, you really should consider a packaged solid state relay. These have additional parts including a snubber. They usually don't need the series resistor.

    If you want to control AC, you shouldn't worry about size. You will need to provide wide PCB traces with large spaces between conductors for adequate current carrying capacity and isolation between conductors. There also needs to be some isolation between the AC portion of the circuit and the logic portion. Otherwise, you have dangerous conditions both for the user and the rest of the circuit.

    Post Edited (Mike Green) : 9/24/2009 5:13:26 AM GMT
  • MichelBMichelB Posts: 154
    edited 2009-09-24 07:29
    Hi Mike, I want also control (from BS2) 220 VAC 2-4 A with a triac trigger + triac. Can you help me for the choice of components? Thank you in advance.
  • bhendrixbhendrix Posts: 9
    edited 2009-09-25 04:12
    Im not sure I was clear about what Im wanting, the controlled voltage will be the input Voltage to the stamp input pin via a shift register more then likely, I will just use the VDD for the current source to be high on the shift register, then shift in the state of the external Switch, button or limit switch.

    Lets say the Voltage that I want to use with the external input circuit is 110AC, I know how the opto works, I thought(and could very well be wrong)that I have seen opto type IC sized relays that were used in this way. and I know I have seen solid state opto relays use 110ac as a control voltage to control a 5vdc load before.
    I am wanting something that can do this in a small package to fit on a PCB with the rest of the circuit.

    I just Looked at the Basic stamp PLC thanks to a cowworker, is that not exctly what was done there? maybe I should just buy that and add a display and 5 button keyboard to it! LOL!

    if you need to know a particular piece of information I will surely supply you with it,

    I have everything else figured out for this, just not what component would be best for relaying a 110VAC or 24VDC Control current to a 5VDC Controlled current.

    THE larger·Voltge I want to use as a controlling·Voltage, the Current·will be·whatever the LED or Coil will draw,·it will never get to the board past the "Relay" I will use!

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "Automated Control of a machine is no more a hobby or a Job·as it is an art form" - Unknown




    Post Edited (bhendrix) : 9/25/2009 4:31:24 AM GMT
  • PJAllenPJAllen Banned Posts: 5,065
    edited 2009-09-25 13:22
    http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=18825&
  • bhendrixbhendrix Posts: 9
    edited 2009-09-25 13:59
    Awsome PJ! thank you, I looked all over Jameco and Mouser, I guess I missed that! your the man!!!!

    and thank you too Mr. Green, I appreciate the help guys

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "Automated Control of a machine is no more a hobby or a Job·as it is an art form" - Unknown


    ·
  • sam_sam_samsam_sam_sam Posts: 2,286
    edited 2009-09-26 12:11
    Look at this as well

    http://www.automationdirect.com/adc/Shopping/Catalog/Relays_-z-_Timers/Solid-State_Relays/AD-SSR225-DC

    or this

    http://document.sharpsma.com/files/s116s01_e.pdf

    and this where you can buy one

    http://www.mouser.com/ProductDetail/Sharp-Microelectronics/S116S01F/?qs=sGAEpiMZZMtLEhJ5P%2fNsZ26P7ZwMB%2fOzL75UfFoV8jY%3d

    I hope this helps


    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    ··Thanks for any·idea.gif·that you may have and all of your time finding them smile.gif

    ·
    ·
    ·
    ·
    Sam

    Post Edited (sam_sam_sam) : 9/26/2009 12:45:13 PM GMT
  • dev/nulldev/null Posts: 381
    edited 2009-09-26 21:08
    4N33: www.taydaelectronics.com/servlet/the-Integrated-Circuits-(-ICs-)-cln-Other-ICs/Categories

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Don't worry. Be happy
  • bhendrixbhendrix Posts: 9
    edited 2009-09-27 02:41
    Thanks guys, I really appreciate all the help!

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "Automated Control of a machine is no more a hobby or a Job·as it is an art form" - Unknown


    ·
Sign In or Register to comment.