100v (japanese) to 120v (usa) on a capacitor motor

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hey smart people,
i have a japanese fan that i want to install in my attic on
thermostat. its from a clean room in japan, running on 100v. ive heard
that i can do this without a transformer, "it will just run hot".
is this true? is there a chance of fire? just how hot? will it likely
smoke in a week? or a year?
thank you

 

[Mike Berger]

That could be a significant overload. Use a transformer or maybe
a light bulb in series. It's not unusual to see 127 volts on the
lines here. Unless there's something very special about the fan
I wouldn't bother.

 

[Homer J Simpson]

i have a japanese fan that i want to install in my attic on
thermostat. its from a clean room in japan, running on 100v. ive heard
that i can do this without a transformer, "it will just run hot".
is this true? is there a chance of fire? just how hot? will it likely
smoke in a week? or a year?

Is the fan 50 or 60 cycle?

 

[Sam Goldwasser]

That could be a significant overload. Use a transformer or maybe
a light bulb in series. It's not unusual to see 127 volts on the
lines here. Unless there's something very special about the fan
I wouldn't bother.

Get a power transformer with a ~20 V secondary rated for the current of
the fan. Then wire the primary across the line, secondary in series with
the fan with reverse polarity. You can probably find a suitable transformer
on eBay.

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[James Sweet]

hey smart people,
i have a japanese fan that i want to install in my attic on
thermostat. its from a clean room in japan, running on 100v. ive heard
that i can do this without a transformer, "it will just run hot".
is this true? is there a chance of fire? just how hot? will it likely
smoke in a week? or a year?
thank you

I would use a transformer. It can be done cheaply by wiring up a 120V to
24V power transformer in a buck configuration. You can get one of these
cheaply from anywhere that sells HVAC surplus. Just make sure the
secondary is rated to handle as much current as the motor draws, it does
not have to be a very big transformer because it is not powering the
full load of the fan.

 

[[email protected]]

thank you very much, that sounds likea great idea.