Results 1 to 5 of 5

Thread: GM20 single channel driver

  1. #1
    Join Date
    Aug 2007
    Location
    Under a rock in Cambridge UK
    Posts
    1,353

    Default GM20 single channel driver

    As title really, if anyone knows where I can get hold of one???

    Thanks
    Mark

  2. #2
    mixedgas's Avatar
    mixedgas is offline Creaky Old Award Winning Bastard Technologist
    Infinitus Excellentia Ion Laser Dominatus
    Join Date
    May 2007
    Location
    A lab with some dripping water on the floor.
    Posts
    9,569

    Default

    Blimey, mate, you do want the proverbial hen's tooth don't you ?

    Most made were 4 or 8 channels.

    However there is a work around.

    While too expensive to use in big installs, you want a OPTO22 module.

    http://www.opto22.com/site/pr_detail...=4&item=DC60S3

    60 VDC 5 Amp model is optimum. Place a reverse diode across the GM20 coil to kill the back EMF and a 20 Ohm, wirewound, resistor across the coil for damping. Wire the coils in series if it is a 4 terminal GM20. The wirewound resistor, if used, can get hot, use a big un. Diode shall be a 1N4007 or larger.

    When you buy the OPTO22 or clone, make sure its rated to switch DC, the AC ones are just a triac and won't switch DC off.

    If I ever really, really, wanted to hurt some one, a GM20 pegged to one side with 12V and allowed to snap back and ring shocks the %hit out of you, huge voltage spike. Thus the damping diode to protect the relay.

    The Opto22 family is optoisolated, so it keeps the spikes and failures out of the controller.

    Steve
    Last edited by mixedgas; 10-06-2010 at 09:02.
    Qui habet Christos, habet Vitam!
    I should have rented the space under my name for advertising.
    When I still could have...

  3. #3
    Join Date
    Nov 2005
    Location
    Melbourne, Australia
    Posts
    3,702

    Default

    Hey Mark,

    is the driver just for a shutter? If you don't need anything fancy, I have some tiny boards that hold a fet and a few other components to run a shutter.
    KVANT Australian projector sales
    https://www.facebook.com/kvantaus/

    Lasershowparts- Laser Parts at great prices
    https://www.facebook.com/lasershowparts/

  4. #4
    Join Date
    Aug 2010
    Location
    London or Spain depending on the weather
    Posts
    1,381

    Default

    Quote Originally Posted by Insanity View Post
    As title really, if anyone knows where I can get hold of one???
    Thanks
    Mark
    If you want to scan with this I might be able to help, but you would have to wait a couple of weeks since I have some open loop amps in Barcelona.

    Unfortunately I won't be going there till next week and won't get back to London till the 25th.

    If you still need them in a week drop me a PM before the 18th and I will dig around for one.

    Cheers

  5. #5
    Join Date
    Aug 2007
    Location
    Under a rock in Cambridge UK
    Posts
    1,353

    Default

    Thanks for all the replys.. I think I might be sorted now...

    Mark

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •