CFL transformer ballast for mains voltage drop

[neazoi]

Can I use a common CFL transformer ballast for dropping out the voltage from 240v to 120vac?
The load draws about 8W at 120V

 

[FvM]

You are asking about 50/60 Hz CFL ballast chokes? They act as constant current source and can work for you if the load has at least proportional (resistive) V/I characteristic or a stiffer characteristic towards constant V.

 

[neazoi]

You are asking about 50/60 Hz CFL ballast chokes? They act as constant current source and can work for you if the load has at least proportional (resistive) V/I characteristic or a stiffer characteristic towards constant V.

Hm... it is to power up a 240v shaded pole motor at hald the voltage (120v, draws 8W there)

The other thing I was thinking was a simple series diode. The diode will cut-off the negative portion of the AC cycle but not completely (0.6v drop) the resulting waveform will be a very distorted AC and the P2P voltage would be around half.

 

[FvM]

Series diode feeds DC to the induction motor and fastly burn the winding. Don't!

I guess a 4W CFL choke can work. A variac or rheostat would allow to adjust the intended voltage.

 

[neazoi]

Series diode feeds DC to the induction motor and fastly burn the winding. Don't!

I guess a 4W CFL choke can work. A variac or rheostat would allow to adjust the intended voltage.

The motor nominal voltage is 240v. So can i connect the primary of a small transformer in series with the motor, to use this as a choke? The primary has some resistance so this might work?

 

[KlausST]

Hi,

With a LF inductor in series I expect low torque.
Better use an autotransformer. Like the ones for 230V/120V for traveling (shaver)

Klaus