Vintage relay search

Discussion in 'General Electronics Chat' started by inwo, Jun 26, 2014.

  1. inwo

    Thread Starter Well-Known Member

    Nov 7, 2013
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    Repaired a brake failure on a 50+ year old overhead crane Monday.

    A cylinder fell out of a coil.

    The problem had them shut down so I had no time to research or even figure out how it failed.

    I just put a clamp top-side on the cylinder to keep it in place.

    First thought was that it was a mercury relay.

    It was marked with "seconds" however. Must be a delay relay.

    I'm doing a search without much success. Anyone know what this might be called?

    Coil part is about 2" square. 1" thick. 1" hole.
    Cylinder part fits thru hole ~5" long.

    I want to be ready for the next time.
     
    Last edited: Jun 26, 2014
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
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    I am guessing the coil is DC powered? Being that old, it could be a oil dash-pot (or?) delay. the piston drives oil out at a per-determined rate.
    Just a guess!

    Getting a replacement may be a head ache :p

    Do you have the Crane schematic?
    Max.
     
    Last edited: Jun 26, 2014
  3. inwo

    Thread Starter Well-Known Member

    Nov 7, 2013
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    The schematic is available. I haven't found the brake control part yet though. It's just shown as a black box.
    Somewhere should even be part numbers.

    No dash-pot control valve or adjustment other than sliding the cylinder.
    Can't picture how that would work.

    Right now I'm just curious. No pressing need.
    Not 100% sure it's a timer.:confused:

    Absolutely amazing how rugged these crane controls were made.

    Just now replacing some contactors and auxiliarys.
    Mostly metal fatigue, not electrical failure. Sometimes it's just a wire terminal broke off next to the screw.
     
  4. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Does the piston part contact/actuate anything else?
    It is not just the pin to operate the brake, is it working in a time delay fashion now?
    I imagine the lift motor is AC wound rotor for speed control?
    Max.
     
  5. inwo

    Thread Starter Well-Known Member

    Nov 7, 2013
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    Kind of like fig.1, but leads come out bottom.
     
  6. MrCarlos

    Active Member

    Jan 2, 2010
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  7. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Seems to be similar that it possess a dash pot delay of some kind?
    Max.
     
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