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    Are there relays made for inductive loads

    Are they relays which are made to drive inductive loads and can subsittute a low side FET for =<140Hz?

    This would be for high voltage transformers from low voltage input.

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    Re: Are there relays made for inductive loads

    Hi,

    Relay and 140Hz ... I doubt you find some.

    Klaus
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    Re: Are there relays made for inductive loads

    assuming a 50/50 duty cycle 140 Hz equals roughly a 3.5 millisecond on time. You are talking small reed-relay response times.

    Reed relays are rated for very low voltages and currents.

    So, I concur with Klaus.....extremely unlikely.
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    Re: Are there relays made for inductive loads

    The desired product is unclear to me.

    AC-coil relays might be a bit funny operated at 140Hz but
    it's not really said, what's the coil drive and what's the
    switched source and load.

    Relays used in air conditioner systems live for inductive loads
    and tend to use 24VAC coil.

    Appliance relays often give different DC/resistive and AC/
    inductive contact rated loads but can be used (within ratings
    and properly snubbed) for both.

    But I think you'd get better options if you were clear about
    what your available drive signal is and the switched source
    & load attributes.


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    Re: Are there relays made for inductive loads

    Mechanical relays aren't fast enough. There aren't solid state relays which can perform for this?



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    Re: Are there relays made for inductive loads

    You need to look carefully at the guts of a SSR. SCR / Triac
    types behave badly with inductive loads (though I have used
    phase-cut dimmers to run series-wound motor tools, neither
    the dimmer nor the tools seemed especially happy about it).

    Still suggest you lay out the particulars more clearly if you
    want to-the-point advice. Not clear what about a 140Hz system
    needs to be so fast.


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    Re: Are there relays made for inductive loads

    DC capable SSR are FET switches. In so far I don't understand why you are asking for a SSR to replace a FET.


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    Re: Are there relays made for inductive loads

    Quote Originally Posted by Zak28 View Post
    Mechanical relays aren't fast enough. There aren't solid state relays which can perform for this?
    Yes, there are Solid State Relays mfr by CRYDOM, that are specifically design and rated for highly inductive loads.


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