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Mercury Relays

  1. Jun 16, 2010 #1
    Hello! This is my first time visiting this forum and I am sure it won't be my last.

    I have a project in which I need to replace some mercury relays because they won't fly international. To give some more info the project is designed to have three amplifiers hooked up to a switch box and choose which amp we want to use on the output to one set of speakers. It has to switch virtually to the point when it is not noticeable, thus the relays.

    These relays are rated 480VAC, 60A, 2 Pole, Normally Open, and the open/close timing is approx. 50ms.

    I need to replace with different relays and need to be around the same specs and honestly don't know a whole lot about relays. I know the basics and thats about it. If anyone knows about some high current/high voltage/fast switching relays that would be great. Would solid-state relays be a good replacement?
  2. jcsd
  3. Jun 16, 2010 #2


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    It sounds like those relays are far better than they need to be. (So, why are you replacing them?)

    An amplifier driving one pair of speakers would probably not be drawing more than 2 amps from the mains.

    So, you need more information. Find out how much current the amplifiers take and at what voltage. Look for something like "230 volts 0.85 amps".
    This will give you information about how good the relay contacts have to be.

    Then try to check what voltage is being applied to the coils of the relays. You need to know this for ordering more relays. It tells you the coil voltage for the relays.
    Also find out if this voltage is AC or DC.
  4. Jun 17, 2010 #3
    I need to replace them because mercury doesn't fly internationally. And the coil voltage was 15Vdc.

    Well the amplifiers that I am going to be using are rated up to 8000 W. Playing at clipping in a 2 ohm stereo/ 4 ohm bridge mono / 1 ohm parallel mono, the current draw is 42.6A. For using this specific box we probably won't be playing at clipping. It will more than likely be 8 ohm bridge which is still rated around 30A. But in case the client wants to hear it switch between amplifiers at clipping the relays should be able to handle it.

    I basically just need to know what a good substitute for a mercury relay would be. I have been looking at a few solid state relays from Teledyne. I just want to make sure that a solid state relay can react and operate like my mercury relays.
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