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Multiple switching relays - circuit requirements

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Blend9684
Blend9684 Member Posts: 14

The instructions for the Taco SR506-5 mention a 20-amp power input, but the wiring diagrams show two wired in parallel on what looks like one circuit with the boiler.

Can two switching relays use the same circuit provided the current draw of all the pumps at once are below 20 amps (or 80% of 20 amps)?

Comments

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 11,588
    edited December 2

    YES. Do you know how many pumps you will be using at the same time if everything calls for heat at once? Do you know the current draw or AMP rating of all those pumps?

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • Joe Mattiello
    Joe Mattiello Member Posts: 748

    I don't see your wiring schematic, but each control has a maximum 20 amp capacity, and the interface between the controls ABC terminals for multiple controls designed for master slave orientation is low voltage. If you have all your 120 voltage inputs daisy chained together you will have maximum voltage based on Circuit breaker rating. If they're all independently wired, you have the maximum of each control.

    Joe Mattiello
    N. E. Regional Manger, Commercial Products
    Taco Comfort Solutions