What to loof for in a VariAC

[Les_Garten]

Hi,

I'm wanting to buy a VariAC. Here's one from MPJA, hows it look?

2KVA 0-130VAC VARIABLE TRANSFORMER-MPJA, Inc.

This one seems to have the amperage to do anything.

Les

[luvdunhill]

Hi,

I'm wanting to buy a VariAC. Here's one from MPJA, hows it look?

2KVA 0-130VAC VARIABLE TRANSFORMER-MPJA, Inc.

This one seems to have the amperage to do anything.

Les

Personally, I wouldn't buy once unless it had 0-250VAC output

[Les_Garten]

Personally, I wouldn't buy once unless it had 0-250VAC output

I see what you're getting at, how about this one? Just as a starting look.

Mastech 5KW VARIABLE TRANSFORMER VARIAC 5000VA 0-250V - eBay (item 380161906580 end time Oct-04-09 17:28:02 PDT)

I have a Mastech DC Power supply and they seem to make serviceable gear for the Hobbyist.

[falkon]

How stable is power coming from a Variac anyway? I know in our lab we use a metered one.

[luvdunhill]

as stable as the power in your wall I'd presume

[n_maher]

as stable as the power in your wall I'd presume

Yeah it's not like it buffers or regulates the voltage as far as I'm aware.

[grenert]

I use the even-cheaper variac from MPJA:

500VA 0-130VAC VARIABLE TRANSFORMER-MPJA, Inc.

It's been fine for low-power applications (DAC and headphone amp power supplies); haven't tried it for heavy-duty projects.

One thing to keep in mind is that the actual output voltage will vary depending on your local AC voltage, so the volt markings on the dial may not correspond to what the variac is really putting out. Check the built-in meter, or better yet, check with your multimeter.

EDIT: It may just be the photograph, but the Mastech you linked to seems to have the voltage knob way off-kilter. Like it was dropped on it's head