Selecting an scr controller for very small electric heater

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Finestein

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Hello everyone/anyone, this is my first post so bear with me.

I am trying to closely control the temperature of air moving slowly and continuously through a duct (~30cfm). I would like to use a very small (250-350W, 120v) finned electric heater to heat this air. I figured a phase angle fired SCR power controller would do the job the best. (I really would like the best control I can get.) I have a temperature controller already with analog outputs, but now I'm looking around for an SCR power controller that could handle this heater. I'm worried because it's such a low power application, the heating element may only be drawing 1A, and the smallest SCR power controllers I can find are rated for 15A.

Would it be a bad idea to use an over-sized SCR power controller (rated for say 15A) on a heating element that will only be drawing around 1A? Are there negative effects (worse temperature control?) for using an over-sized SCR power controller for this application? Or is there somewhere I can get a phase angle SCR power controller that's rated better for this smaller application?

Thank you very much.
 
Can one buy a light dimmer that can be controlled by a 0-20mA or 0-10Vdc analog output signal from a proportional temperature controller?
 
Googling "voltage-controlled light dimmer" gives many hits which may be useful, particularly if you want to go the DIY route.
 
Okay Thank you. I am a beginner to electronics, so hopefully I will be able to find some prefabricated voltage-controlled light dimmer. But I suppose I can learn if there aren't any out there.
 
In N.A. these are plentiful at most H.W. stores.
For more info on DIY control solutions see the Fairchild AN-3006.
Max.
 
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