Pyrography

Just a question - what would happen if one was to use a simple commercial lamp dimmer of the appropriate power rating on the primary of the transformer to adjust the power delivered to the heating loop?

Quick & dirty?

Yes. It would probably blow the fuse or breaker instantly.

I made a hot wire cutter from a MOT and a commercial lamp dimmer years ago. Elegant? No. Quick & dirty? Yes. Blows fuses or pops breakers? No. Interferes with other electrical/electronic devices? No. The transformer does buzz a bit but it works fine. Caveat: I only use it for about 5 -10 minutes at a time. Art

Transformers tend to not get along with triac dimmers. Use a Variac into the transformer.

On a sunny day (Mon, 17 Nov 2014 13:27:31 -0800) it happened John Larkin wrote in :

I was thinking about that. Long time ago I tried it, and it worked,. The thing to look out for is the triac does not fire symmetricaly in both the negative and positive cycle, you get DC in the transformer, saturation and bang,

Anyways it worked, maybe I was just lucky.

That works.

Yep, I've seen it done before.

I'm sure it was in a commercial application but I cannot remember the application.

True for many dimmers. But there are dimmers that are intended to work into transformers, such as low voltage under-cabinet lights. The dimmer feeds chopped line 120 Vac voltage to the transformer, which steps it down to 12 Vac for a string of incandescent lamps.

I like and use such dimmers made by Lutron.

Joe Gwinn

------------------------- Is there some schematics for such stuff. It's quite urgent so i dont have much time left for r&d..