Question for Electronics Wizards

[Donald Miller]

Does anyone know of a good circuit for a user variable power supply with 115/60hz or 230/50hz input and 40-100% variable output? Power load will be 1500 watt resistive.

I realize that I could go to a SCR to convert to DC but would rather not go that route.

Thanks for your help.

 

[ras351]

This is not really my area of electronics expertise so perhaps someone in the know can provide further insight but my initial thoughts would be to use a triac. Similar to a SCR but conducts in both directions and so can be used to control AC. A google search should turn up something - they get used in light dimmer circuits but you should be able to find something beefier that'll handle 1400W. Variable speed vacuum cleaners might also be another source.

Roger.

 

[Sparky]

get a variac! it'd be killer. you can find them on ebay probably. they're KINDA expensive. But dead stable.

 

[Marco Gilardetti]

Triacs inject a lot of noise in the circuit and I doubt that one able to handle 1.4 kW could be found easily.

I agree on the Variac advice.

 

[Donald Miller]

Thanks everyone. This gives me direction. I appreciate it.

 

[GeorgesGiralt]

Hi !
Look at high power halogen lamps and their controlling "rheostat" as they are often called.
In my office at work we have one suited for a 1KW load (the lamp fixture uses 2 bulbs 500 W each) and is quite well filtered for noise (we run electronics complaining if badly fed). they can be bought as replacement quite cheaply as, you know, they're made in China...
The one I see is put on the floor and has a sort of pedal to adjust it. the plastic case is sturdy.
Go to the biggest stockist of lamp fixture in your town and ask. You may be impressed by the devices availlable and the cheap price they ask for.

 

[BarryWilkinson]

I'll second the Variac.

Barry