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Impedance Relays

Hi Carol,In AC units ,some mfrg's have "lock-out control" which uses "impedance relays" .How are these relays different than regular relays? Thank You!


  • Empire_2
    Empire_2 Member Posts: 2,343

    The relays in question are usually of a higher resistance. The only time they will energise is if a safety control opens 1 time, then the path of least resistance will now go to the lockout relay to keep the equipment off because one of the contacts from the LOR is in the origional circuit. Circuit has to be reset to get system back on line. There are however small circuit boards that do the same think such as found in carrier compressor lock out controls.

    Mike T.
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