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can a variable speed controller run a relay?

Discussion in 'Alternative Energy' started by mtmtntop, Apr 25, 2009.

  1. mtmtntop

    mtmtntop New Member

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    i have a tekmar 157 controller which runs the primary pump for a solar array at a variable speed. i was wondering if i can run a 120 v relay off of this lead. i am unsure if varying the speed affects the voltage or amperage. if it reduces the voltage, i do not think it can operate the coil. anyone know? thanks
     
  2. Willbe

    Willbe New Member

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    tekmar Difference Setpoint Control 157
    I can't tell from this link.
    Relays generally pull in at 2/3rds rated voltage and drop out at 1/3rd rated v.
     
  3. mtmtntop

    mtmtntop New Member

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    thats more than i knew. thanks alot. i'll have to rethink my plan.
     
  4. dave

    Dave New Member

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  5. kchriste

    kchriste New Member Forum Supporter

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    Can you use the secondary pump output in Mode1 to drive the relay?

     
    Last edited: Apr 25, 2009
  6. mtmtntop

    mtmtntop New Member

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    no, that won't work. i wanted to open a zone valve when the primary pump was activated. it looks like i may have to do this via an aquastat and temp sensor.
     
  7. mtmtntop

    mtmtntop New Member

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    on second thought maybe it will. re reading your post, it has power whenever the pump 1 is operating greater than zero. i hadn't thought of using the p2 lead. thanks alot! i guess i need to read the instructions more creatively next time.
     
  8. Thunderchild

    Thunderchild New Member

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    you may be able to introduce further control circuitry
     

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